<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019e22d7-d897-7ca5-bdfd-043e7c24aa6c,g:b79b97ce-1fb8-4252-a96f-ea718e7a3d21-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/CONSOLIDATEDSTATEMENTSOFCONVERTIBLEPREFERREDSTOCKANDSHAREHOLDERSEQUITYUnaudited" xlink:type="simple" xlink:href="sbcf-20260630.xsd#CONSOLIDATEDSTATEMENTSOFCONVERTIBLEPREFERREDSTOCKANDSHAREHOLDERSEQUITYUnaudited"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/CONSOLIDATEDSTATEMENTSOFCONVERTIBLEPREFERREDSTOCKANDSHAREHOLDERSEQUITYUnaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019e22d7-dc20-71f8-979d-7faa235bb946" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019e22d7-dc20-7cdc-b2c4-c269ee172cbe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019e22d7-dc20-71f8-979d-7faa235bb946" xlink:to="loc_us-gaap_StatementTable_019e22d7-dc20-7cdc-b2c4-c269ee172cbe" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019e22d7-dc20-7faa-9ddb-a51514b2ce9e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019e22d7-dc20-7cdc-b2c4-c269ee172cbe" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019e22d7-dc20-7faa-9ddb-a51514b2ce9e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e22d7-dc20-7faa-9ddb-a51514b2ce9e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e22d7-dc20-7faa-9ddb-a51514b2ce9e" xlink:to="loc_us-gaap_EquityComponentDomain_019e22d7-dc20-7faa-9ddb-a51514b2ce9e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e22d7-dc20-76d1-8a33-2e627c88dd3c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e22d7-dc20-7faa-9ddb-a51514b2ce9e" xlink:to="loc_us-gaap_EquityComponentDomain_019e22d7-dc20-76d1-8a33-2e627c88dd3c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019e22d7-dc20-79ab-a37c-43dbb38b3458" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e22d7-dc20-76d1-8a33-2e627c88dd3c" xlink:to="loc_us-gaap_CommonStockMember_019e22d7-dc20-79ab-a37c-43dbb38b3458" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_019e22d7-dc20-7ffa-a627-2c08e942c6a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e22d7-dc20-76d1-8a33-2e627c88dd3c" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_019e22d7-dc20-7ffa-a627-2c08e942c6a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_019e22d7-dc20-7679-a20a-172a9fb005a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e22d7-dc20-76d1-8a33-2e627c88dd3c" xlink:to="loc_us-gaap_RetainedEarningsMember_019e22d7-dc20-7679-a20a-172a9fb005a4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_019e22d7-dc20-7302-b240-55cf43d466e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e22d7-dc20-76d1-8a33-2e627c88dd3c" xlink:to="loc_us-gaap_TreasuryStockCommonMember_019e22d7-dc20-7302-b240-55cf43d466e8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e22d7-dc20-72b8-89a4-b321ba915c46" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e22d7-dc20-76d1-8a33-2e627c88dd3c" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e22d7-dc20-72b8-89a4-b321ba915c46" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInTemporaryEquityRollForward_019e397a-e6f6-7bc1-bcd3-72e25616c737" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInTemporaryEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e22d7-dc20-71f8-979d-7faa235bb946" xlink:to="loc_us-gaap_IncreaseDecreaseInTemporaryEquityRollForward_019e397a-e6f6-7bc1-bcd3-72e25616c737" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TemporaryEquitySharesOutstanding_019e397b-e5e0-71a5-ba2b-c18efea85b8d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TemporaryEquitySharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInTemporaryEquityRollForward_019e397a-e6f6-7bc1-bcd3-72e25616c737" xlink:to="loc_us-gaap_TemporaryEquitySharesOutstanding_019e397b-e5e0-71a5-ba2b-c18efea85b8d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TemporaryEquityCarryingAmountAttributableToParent_019e397c-2b31-73ad-a94d-46dcc4d41ae9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TemporaryEquityCarryingAmountAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInTemporaryEquityRollForward_019e397a-e6f6-7bc1-bcd3-72e25616c737" xlink:to="loc_us-gaap_TemporaryEquityCarryingAmountAttributableToParent_019e397c-2b31-73ad-a94d-46dcc4d41ae9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TemporaryEquitySharesOutstanding_019e397c-69b7-7d0f-b0c3-07d7d3624a68" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TemporaryEquitySharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TemporaryEquityCarryingAmountAttributableToParent_019e397c-b2e2-74d7-9d20-92f8006e338d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TemporaryEquityCarryingAmountAttributableToParent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e22d7-dc20-71f8-979d-7faa235bb946" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019e22d7-dc20-72dd-9577-05685c5ab573" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_019e22d7-dc20-72dd-9577-05685c5ab573" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e22d7-dc20-788d-a78e-680672e04d47" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_us-gaap_StockholdersEquity_019e22d7-dc20-788d-a78e-680672e04d47" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_019e22d7-dc20-741b-a371-8ae8e71dc45a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTax_019e22d7-dc20-741b-a371-8ae8e71dc45a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019e22d7-dc20-7749-80be-759c0c2e0bbf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019e22d7-dc20-7749-80be-759c0c2e0bbf" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_StockIssuedDuringPeriodSharesCommonStockTransactionsRelatedToEmployeeBenefitPlans_019fa3f3-7558-7f51-94a9-093ee77b23f4" xlink:href="sbcf-20260630.xsd#sbcf_StockIssuedDuringPeriodSharesCommonStockTransactionsRelatedToEmployeeBenefitPlans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_sbcf_StockIssuedDuringPeriodSharesCommonStockTransactionsRelatedToEmployeeBenefitPlans_019fa3f3-7558-7f51-94a9-093ee77b23f4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeBenefitPlan_019e22d7-dc20-7178-8f2a-5be3cf2f3d6d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeBenefitPlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeBenefitPlan_019e22d7-dc20-7178-8f2a-5be3cf2f3d6d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_StockIssuedDuringPeriodValueCommonStockTransactionsRelatedToEmployeeBenefitPlans_019e22d7-dc20-7f76-9a42-2c256528a495" xlink:href="sbcf-20260630.xsd#sbcf_StockIssuedDuringPeriodValueCommonStockTransactionsRelatedToEmployeeBenefitPlans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_sbcf_StockIssuedDuringPeriodValueCommonStockTransactionsRelatedToEmployeeBenefitPlans_019e22d7-dc20-7f76-9a42-2c256528a495" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_019f85aa-fcf8-722c-bce7-95d907edd1c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_019f85aa-fcf8-722c-bce7-95d907edd1c1" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_019f85ab-2cc2-7654-a59e-5340a922924b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_019f85ab-2cc2-7654-a59e-5340a922924b" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStock_019e22d7-dc20-76e0-ba7e-408fd5c5d89d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_us-gaap_DividendsCommonStock_019e22d7-dc20-76e0-ba7e-408fd5c5d89d" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsPreferredStock_019e5e1b-b00e-79e2-8dfa-b6120dc62a71" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsPreferredStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_us-gaap_DividendsPreferredStock_019e5e1b-b00e-79e2-8dfa-b6120dc62a71" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesPeriodIncreaseDecrease_019e22d7-dc20-7f69-b9db-4bed7a0464fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesPeriodIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesPeriodIncreaseDecrease_019e22d7-dc20-7f69-b9db-4bed7a0464fa" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityPeriodIncreaseDecrease_019e22d7-dc20-7f65-a370-3ade7bdc9723" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityPeriodIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e22d7-dc20-77da-9898-554ac2109df3" xlink:to="loc_us-gaap_StockholdersEquityPeriodIncreaseDecrease_019e22d7-dc20-7f65-a370-3ade7bdc9723" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019e22d7-dc20-772e-8705-efc02625092e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e22d7-dc20-73c2-b500-e95fed2cd4db" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/SecuritiesScheduleofAmortizedCostandFairValueofSecuritiesAvailableforSaleandHeldforInvestmentDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#SecuritiesScheduleofAmortizedCostandFairValueofSecuritiesAvailableforSaleandHeldforInvestmentDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/SecuritiesScheduleofAmortizedCostandFairValueofSecuritiesAvailableforSaleandHeldforInvestmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7df4-bb24-9748d4b07252" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e22d7-dcd1-778e-89aa-2056160a6314" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7df4-bb24-9748d4b07252" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e22d7-dcd1-778e-89aa-2056160a6314" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7bf6-b1e3-8cbdc4b5e55f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e22d7-dcd1-778e-89aa-2056160a6314" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7bf6-b1e3-8cbdc4b5e55f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7bf6-b1e3-8cbdc4b5e55f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7bf6-b1e3-8cbdc4b5e55f" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7bf6-b1e3-8cbdc4b5e55f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a38-84eb-b7c78d2b8e7f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7bf6-b1e3-8cbdc4b5e55f" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a38-84eb-b7c78d2b8e7f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_019e22d7-dcd1-774c-80ab-42141e49da22" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a38-84eb-b7c78d2b8e7f" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_019e22d7-dcd1-774c-80ab-42141e49da22" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_019e22d7-dcd1-759b-87be-4e55ca54f027" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a38-84eb-b7c78d2b8e7f" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_019e22d7-dcd1-759b-87be-4e55ca54f027" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_019e22d7-dcd1-756a-ba01-0aeb5bd8a3b4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a38-84eb-b7c78d2b8e7f" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_019e22d7-dcd1-756a-ba01-0aeb5bd8a3b4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e22d7-dcd1-78e6-9e4f-e96ccd827869" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a38-84eb-b7c78d2b8e7f" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e22d7-dcd1-78e6-9e4f-e96ccd827869" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralizedLoanObligationsMember_019e22d7-dcd1-7cdd-ae1b-025f161e2851" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CollateralizedLoanObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a38-84eb-b7c78d2b8e7f" xlink:to="loc_us-gaap_CollateralizedLoanObligationsMember_019e22d7-dcd1-7cdd-ae1b-025f161e2851" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e22d7-dcd1-7945-b456-fb191c1abdfd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a38-84eb-b7c78d2b8e7f" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e22d7-dcd1-7945-b456-fb191c1abdfd" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherDebtSecuritiesMember_019e22d7-dcd1-7152-b746-6ebce90c171c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a38-84eb-b7c78d2b8e7f" xlink:to="loc_us-gaap_OtherDebtSecuritiesMember_019e22d7-dcd1-7152-b746-6ebce90c171c" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract_019e22d7-dcd1-71f5-a500-bc8d6dad4cc4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7df4-bb24-9748d4b07252" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract_019e22d7-dcd1-71f5-a500-bc8d6dad4cc4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-75e2-96f0-292b1d0d682b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract_019e22d7-dcd1-71f5-a500-bc8d6dad4cc4" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-75e2-96f0-292b1d0d682b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_019e22d7-dcd1-7016-926a-55b4bd59be2a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract_019e22d7-dcd1-71f5-a500-bc8d6dad4cc4" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_019e22d7-dcd1-7016-926a-55b4bd59be2a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_019e22d7-dcd1-740e-a705-8a8d776e55df" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract_019e22d7-dcd1-71f5-a500-bc8d6dad4cc4" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_019e22d7-dcd1-740e-a705-8a8d776e55df" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019e22d7-dcd1-7b25-8c0b-67cde96512ef" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesFairValueToAmortizedCostBasisAbstract_019e22d7-dcd1-71f5-a500-bc8d6dad4cc4" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019e22d7-dcd1-7b25-8c0b-67cde96512ef" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesAbstract_019e22d7-dcd1-7b3d-a980-1b17de05229d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7df4-bb24-9748d4b07252" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesAbstract_019e22d7-dcd1-7b3d-a980-1b17de05229d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7c88-9733-3026f7ce3945" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesAbstract_019e22d7-dcd1-7b3d-a980-1b17de05229d" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7c88-9733-3026f7ce3945" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain_019e22d7-dcd1-7779-ad52-d367e4954ffd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesAbstract_019e22d7-dcd1-7b3d-a980-1b17de05229d" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain_019e22d7-dcd1-7779-ad52-d367e4954ffd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss_019e22d7-dcd1-70fb-96fb-03369bc82c10" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesAbstract_019e22d7-dcd1-7b3d-a980-1b17de05229d" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss_019e22d7-dcd1-70fb-96fb-03369bc82c10" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesFairValue_019e22d7-dcd1-775b-ac68-0da9524986a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesAbstract_019e22d7-dcd1-7b3d-a980-1b17de05229d" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesFairValue_019e22d7-dcd1-775b-ac68-0da9524986a1" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/SecuritiesNarrativeDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#SecuritiesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/SecuritiesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e22d7-dcd1-75a8-a713-fb76a957e729" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e22d7-dcd1-75a8-a713-fb76a957e729" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7aeb-ad15-4a8195fc6f44" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e22d7-dcd1-75a8-a713-fb76a957e729" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7aeb-ad15-4a8195fc6f44" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7aeb-ad15-4a8195fc6f44_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7aeb-ad15-4a8195fc6f44" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7aeb-ad15-4a8195fc6f44_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7d22-ae76-666f6653c064" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7aeb-ad15-4a8195fc6f44" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7d22-ae76-666f6653c064" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CRAQualifiedDebtSecuritiesMember_019e22d7-dcd1-737f-8a2e-efa49d8c25bd" xlink:href="sbcf-20260630.xsd#sbcf_CRAQualifiedDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7d22-ae76-666f6653c064" xlink:to="loc_sbcf_CRAQualifiedDebtSecuritiesMember_019e22d7-dcd1-737f-8a2e-efa49d8c25bd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_019e22d7-dcd1-7784-a236-930fd74f7137" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7d22-ae76-666f6653c064" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_019e22d7-dcd1-7784-a236-930fd74f7137" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e22d7-dcd1-7a1a-9127-7acc07b5ed6a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7d22-ae76-666f6653c064" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e22d7-dcd1-7a1a-9127-7acc07b5ed6a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e22d7-dcd1-77a4-867e-c91d4978f5b0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7d22-ae76-666f6653c064" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e22d7-dcd1-77a4-867e-c91d4978f5b0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralizedLoanObligationsMember_019e22d7-dcd1-75fd-b209-a60c39427962" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CollateralizedLoanObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7d22-ae76-666f6653c064" xlink:to="loc_us-gaap_CollateralizedLoanObligationsMember_019e22d7-dcd1-75fd-b209-a60c39427962" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e22d7-dcd1-71ef-8fca-6ceb66bd0085" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7d22-ae76-666f6653c064" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e22d7-dcd1-71ef-8fca-6ceb66bd0085" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherDebtSecuritiesMember_019eb1e6-aad9-7b12-8399-b9cd93ddc2e9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7d22-ae76-666f6653c064" xlink:to="loc_us-gaap_OtherDebtSecuritiesMember_019eb1e6-aad9-7b12-8399-b9cd93ddc2e9" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PledgedStatusAxis_019e399f-e253-7097-a89c-41cb22ea8ff7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgedStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e22d7-dcd1-75a8-a713-fb76a957e729" xlink:to="loc_us-gaap_PledgedStatusAxis_019e399f-e253-7097-a89c-41cb22ea8ff7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PledgedStatusDomain_019e399f-e253-7097-a89c-41cb22ea8ff7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgedStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PledgedStatusAxis_019e399f-e253-7097-a89c-41cb22ea8ff7" xlink:to="loc_us-gaap_PledgedStatusDomain_019e399f-e253-7097-a89c-41cb22ea8ff7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PledgedStatusDomain_019e399f-e253-759c-87e6-25ba718a78b4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgedStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PledgedStatusAxis_019e399f-e253-7097-a89c-41cb22ea8ff7" xlink:to="loc_us-gaap_PledgedStatusDomain_019e399f-e253-759c-87e6-25ba718a78b4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetPledgedAsCollateralMember_019e39a0-0e11-74df-a0de-4ae20dabc821" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetPledgedAsCollateralMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PledgedStatusDomain_019e399f-e253-759c-87e6-25ba718a78b4" xlink:to="loc_us-gaap_AssetPledgedAsCollateralMember_019e39a0-0e11-74df-a0de-4ae20dabc821" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CreditRatingStandardPoorsAxis_019e39a2-497d-7041-8461-f16d5f45e76f" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CreditRatingStandardPoorsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e22d7-dcd1-75a8-a713-fb76a957e729" xlink:to="loc_srt_CreditRatingStandardPoorsAxis_019e39a2-497d-7041-8461-f16d5f45e76f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ExternalCreditRatingStandardPoorsMember_019e39a2-497d-7041-8461-f16d5f45e76f_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ExternalCreditRatingStandardPoorsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CreditRatingStandardPoorsAxis_019e39a2-497d-7041-8461-f16d5f45e76f" xlink:to="loc_srt_ExternalCreditRatingStandardPoorsMember_019e39a2-497d-7041-8461-f16d5f45e76f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ExternalCreditRatingStandardPoorsMember_019e39a2-497d-7896-9dfa-63ae87579416" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ExternalCreditRatingStandardPoorsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CreditRatingStandardPoorsAxis_019e39a2-497d-7041-8461-f16d5f45e76f" xlink:to="loc_srt_ExternalCreditRatingStandardPoorsMember_019e39a2-497d-7896-9dfa-63ae87579416" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StandardPoorsAAARatingMember_019e39a2-7637-770f-abe4-296e5d745bd2" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StandardPoorsAAARatingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ExternalCreditRatingStandardPoorsMember_019e39a2-497d-7896-9dfa-63ae87579416" xlink:to="loc_srt_StandardPoorsAAARatingMember_019e39a2-7637-770f-abe4-296e5d745bd2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StandardPoorsAARatingMember_019e39a3-366f-7e41-aeb0-16605be8bc0f" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StandardPoorsAARatingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ExternalCreditRatingStandardPoorsMember_019e39a2-497d-7896-9dfa-63ae87579416" xlink:to="loc_srt_StandardPoorsAARatingMember_019e39a3-366f-7e41-aeb0-16605be8bc0f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ProceedsFromSaleOfDebtSecuritiesAvailableForSaleIncludingLegacySecurities_019e22d7-dcd1-74ca-b360-4186a0b6f138" xlink:href="sbcf-20260630.xsd#sbcf_ProceedsFromSaleOfDebtSecuritiesAvailableForSaleIncludingLegacySecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_sbcf_ProceedsFromSaleOfDebtSecuritiesAvailableForSaleIncludingLegacySecurities_019e22d7-dcd1-74ca-b360-4186a0b6f138" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleRealizedLoss_019e22d7-dcd1-7116-8817-78e09773d205" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleRealizedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleRealizedLoss_019e22d7-dcd1-7116-8817-78e09773d205" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleRealizedGain_019e22d7-dcd1-7e13-bfa8-dbcaf21aa7f1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleRealizedGain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleRealizedGain_019e22d7-dcd1-7e13-bfa8-dbcaf21aa7f1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentsOwnedAtFairValue_019e22d7-dcd1-7f52-8b39-225e563a687c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentsOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_us-gaap_FinancialInstrumentsOwnedAtFairValue_019e22d7-dcd1-7f52-8b39-225e563a687c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_019e22d7-dcd1-780e-be0c-e1dec4ac6e67" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_019e22d7-dcd1-780e-be0c-e1dec4ac6e67" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_019e22d7-dcd1-71d5-b284-217c0fdaa453" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_019e22d7-dcd1-71d5-b284-217c0fdaa453" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest_019e22d7-dcd1-75b9-ac19-a4286d7a6812" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest_019e22d7-dcd1-75b9-ac19-a4286d7a6812" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_DebtSecuritiesAvailableforsaleUnrealizedLossPositionAverageCreditSupport_019e22d7-dcd1-7952-a6a0-e0ce5b9401d6" xlink:href="sbcf-20260630.xsd#sbcf_DebtSecuritiesAvailableforsaleUnrealizedLossPositionAverageCreditSupport"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_sbcf_DebtSecuritiesAvailableforsaleUnrealizedLossPositionAverageCreditSupport_019e22d7-dcd1-7952-a6a0-e0ce5b9401d6" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_DebtSecuritiesAvailableforsaleUnrealizedLossPositionNumberofPositionsPercentageOfTotal_019e22d7-dcd1-7c56-8c88-db45c397c638" xlink:href="sbcf-20260630.xsd#sbcf_DebtSecuritiesAvailableforsaleUnrealizedLossPositionNumberofPositionsPercentageOfTotal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_sbcf_DebtSecuritiesAvailableforsaleUnrealizedLossPositionNumberofPositionsPercentageOfTotal_019e22d7-dcd1-7c56-8c88-db45c397c638" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest_019e22d7-dcd1-7859-aea1-5c46abb259a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterest_019e22d7-dcd1-7859-aea1-5c46abb259a4" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankStockAndFederalReserveBankStock_019e22d7-dcd1-7e9f-9d2e-476e5af2284e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FederalHomeLoanBankStockAndFederalReserveBankStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_us-gaap_FederalHomeLoanBankStockAndFederalReserveBankStock_019e22d7-dcd1-7e9f-9d2e-476e5af2284e" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7ee4-ba99-aa803ce47406" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7ee4-ba99-aa803ce47406" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7f85-ab38-cd0579c11207" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7f85-ab38-cd0579c11207" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesFvNi_019e22d7-dcd1-776b-841a-d50356b99797" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesFvNi"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-7f60-a9bf-3af1115c41f0" xlink:to="loc_us-gaap_EquitySecuritiesFvNi_019e22d7-dcd1-776b-841a-d50356b99797" xlink:type="arc" order="13"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/SecuritiesScheduleofAmortizedCostandFairValueofSecuritiesbyContractualMaturityDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#SecuritiesScheduleofAmortizedCostandFairValueofSecuritiesbyContractualMaturityDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/SecuritiesScheduleofAmortizedCostandFairValueofSecuritiesbyContractualMaturityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesLineItems_019e22d7-dcd1-7dbe-a688-6427b7eceb25" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfHeldToMaturitySecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesTable_019e22d7-dcd1-7e72-97fa-c1cc6672d53a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfHeldToMaturitySecuritiesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesLineItems_019e22d7-dcd1-7dbe-a688-6427b7eceb25" xlink:to="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesTable_019e22d7-dcd1-7e72-97fa-c1cc6672d53a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7629-8d85-77f81b2e9b99" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesTable_019e22d7-dcd1-7e72-97fa-c1cc6672d53a" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7629-8d85-77f81b2e9b99" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7629-8d85-77f81b2e9b99_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7629-8d85-77f81b2e9b99" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7629-8d85-77f81b2e9b99_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7cbb-809d-f3043ee3d825" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7629-8d85-77f81b2e9b99" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7cbb-809d-f3043ee3d825" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_019e22d7-dcd1-7b79-b841-409063719fc4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7cbb-809d-f3043ee3d825" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_019e22d7-dcd1-7b79-b841-409063719fc4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_019e22d7-dcd1-7699-be13-d0fc27e08ea3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7cbb-809d-f3043ee3d825" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_019e22d7-dcd1-7699-be13-d0fc27e08ea3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e22d7-dcd1-7d94-a06b-276a0ca633c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7cbb-809d-f3043ee3d825" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e22d7-dcd1-7d94-a06b-276a0ca633c6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralizedLoanObligationsMember_019e22d7-dcd1-7f14-befc-068194981948" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CollateralizedLoanObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7cbb-809d-f3043ee3d825" xlink:to="loc_us-gaap_CollateralizedLoanObligationsMember_019e22d7-dcd1-7f14-befc-068194981948" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherDebtSecuritiesMember_019e22d7-dcd1-7fe0-bb23-35a47dac44f6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7cbb-809d-f3043ee3d825" xlink:to="loc_us-gaap_OtherDebtSecuritiesMember_019e22d7-dcd1-7fe0-bb23-35a47dac44f6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAbstract_019e22d7-dcd1-7b56-9602-42b5d92a7e6e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesLineItems_019e22d7-dcd1-7dbe-a688-6427b7eceb25" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAbstract_019e22d7-dcd1-7b56-9602-42b5d92a7e6e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAbstract_019e22d7-dcd1-79f7-aa5b-1e50bf22a46d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAbstract_019e22d7-dcd1-7b56-9602-42b5d92a7e6e" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAbstract_019e22d7-dcd1-79f7-aa5b-1e50bf22a46d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateYearOne_019e22d7-dcd1-7bec-9479-da4f543a0f5d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateYearOne"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAbstract_019e22d7-dcd1-79f7-aa5b-1e50bf22a46d" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateYearOne_019e22d7-dcd1-7bec-9479-da4f543a0f5d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughFive_019e22d7-dcd1-7436-b420-bcc1cd39f99a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughFive"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAbstract_019e22d7-dcd1-79f7-aa5b-1e50bf22a46d" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughFive_019e22d7-dcd1-7436-b420-bcc1cd39f99a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear5Through10_019e22d7-dcd1-7755-88c5-277428615d8e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear5Through10"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAbstract_019e22d7-dcd1-79f7-aa5b-1e50bf22a46d" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear5Through10_019e22d7-dcd1-7755-88c5-277428615d8e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear10_019e22d7-dcd1-7ef8-903c-8e14ea4d501a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear10"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAbstract_019e22d7-dcd1-79f7-aa5b-1e50bf22a46d" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAfterYear10_019e22d7-dcd1-7ef8-903c-8e14ea4d501a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDate_019e22d7-dcd1-7de5-9b8c-51c44ddf5e6a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAbstract_019e22d7-dcd1-79f7-aa5b-1e50bf22a46d" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDate_019e22d7-dcd1-7de5-9b8c-51c44ddf5e6a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityWithoutSingleMaturityDate_019e22d7-dcd1-7bb6-bd85-05ec656e3429" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityWithoutSingleMaturityDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAbstract_019e22d7-dcd1-79f7-aa5b-1e50bf22a46d" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityWithoutSingleMaturityDate_019e22d7-dcd1-7bb6-bd85-05ec656e3429" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7bf7-8ef9-ec2d5094e145" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtSecuritiesHeldToMaturityAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossMaturityAllocatedAndSingleMaturityDateAbstract_019e22d7-dcd1-79f7-aa5b-1e50bf22a46d" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7bf7-8ef9-ec2d5094e145" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValueAbstract_019e22d7-dcd1-73fc-ba5d-3d51084deb4e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValueAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAbstract_019e22d7-dcd1-7b56-9602-42b5d92a7e6e" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValueAbstract_019e22d7-dcd1-73fc-ba5d-3d51084deb4e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue_019e22d7-dcd1-7133-b580-dcdb11e8c1d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValueAbstract_019e22d7-dcd1-73fc-ba5d-3d51084deb4e" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue_019e22d7-dcd1-7133-b580-dcdb11e8c1d4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_019e22d7-dcd1-7e73-9f12-a5f91cd0dcb5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValueAbstract_019e22d7-dcd1-73fc-ba5d-3d51084deb4e" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_019e22d7-dcd1-7e73-9f12-a5f91cd0dcb5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_019e22d7-dcd1-7999-860c-e4df848860e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValueAbstract_019e22d7-dcd1-73fc-ba5d-3d51084deb4e" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_019e22d7-dcd1-7999-860c-e4df848860e7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue_019e22d7-dcd1-7b1c-bf21-ff4610d67f98" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValueAbstract_019e22d7-dcd1-73fc-ba5d-3d51084deb4e" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue_019e22d7-dcd1-7b1c-bf21-ff4610d67f98" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue_019e22d7-dcd1-7bfd-abfe-1ad5a3dbca43" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValueAbstract_019e22d7-dcd1-73fc-ba5d-3d51084deb4e" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValue_019e22d7-dcd1-7bfd-abfe-1ad5a3dbca43" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue_019e22d7-dcd1-70a8-86aa-3ca93da91a85" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValueAbstract_019e22d7-dcd1-73fc-ba5d-3d51084deb4e" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue_019e22d7-dcd1-70a8-86aa-3ca93da91a85" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesFairValue_019e22d7-dcd1-7b77-b5b6-f3cb4e2275e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HeldToMaturitySecuritiesFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesDebtMaturitiesSingleMaturityDateFairValueAbstract_019e22d7-dcd1-73fc-ba5d-3d51084deb4e" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesFairValue_019e22d7-dcd1-7b77-b5b6-f3cb4e2275e0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_019e22d7-dcd1-718b-96a4-79b876678d07" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfHeldToMaturitySecuritiesLineItems_019e22d7-dcd1-7dbe-a688-6427b7eceb25" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_019e22d7-dcd1-718b-96a4-79b876678d07" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e22d7-dcd1-71e4-9b13-e7ce6ff94d05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_019e22d7-dcd1-718b-96a4-79b876678d07" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e22d7-dcd1-71e4-9b13-e7ce6ff94d05" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_019e22d7-dcd1-796e-8d7e-890d30100f7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e22d7-dcd1-71e4-9b13-e7ce6ff94d05" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost_019e22d7-dcd1-796e-8d7e-890d30100f7c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_019e22d7-dcd1-73bf-b246-711c3f68eb95" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e22d7-dcd1-71e4-9b13-e7ce6ff94d05" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost_019e22d7-dcd1-73bf-b246-711c3f68eb95" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost_019e22d7-dcd1-799c-8e3c-9a3bab90bd91" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e22d7-dcd1-71e4-9b13-e7ce6ff94d05" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost_019e22d7-dcd1-799c-8e3c-9a3bab90bd91" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis_019e22d7-dcd1-7645-ae03-8e1fc22504be" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e22d7-dcd1-71e4-9b13-e7ce6ff94d05" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis_019e22d7-dcd1-7645-ae03-8e1fc22504be" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis_019e22d7-dcd1-76b6-bb79-1b414aedd403" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e22d7-dcd1-71e4-9b13-e7ce6ff94d05" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis_019e22d7-dcd1-76b6-bb79-1b414aedd403" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost_019e22d7-dcd1-73ea-8877-c67ac2c4bd93" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e22d7-dcd1-71e4-9b13-e7ce6ff94d05" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost_019e22d7-dcd1-73ea-8877-c67ac2c4bd93" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7db9-bec1-36c45ee192ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostAbstract_019e22d7-dcd1-71e4-9b13-e7ce6ff94d05" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7db9-bec1-36c45ee192ba" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e22d7-dcd1-70de-b13f-42097df11715" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAbstract_019e22d7-dcd1-718b-96a4-79b876678d07" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e22d7-dcd1-70de-b13f-42097df11715" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_019e22d7-dcd1-77bd-ad0b-5c392a07d680" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e22d7-dcd1-70de-b13f-42097df11715" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_019e22d7-dcd1-77bd-ad0b-5c392a07d680" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_019e22d7-dcd1-7d5a-932b-e53a479db8f3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e22d7-dcd1-70de-b13f-42097df11715" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue_019e22d7-dcd1-7d5a-932b-e53a479db8f3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_019e22d7-dcd1-7567-b7e9-729ad3a37168" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e22d7-dcd1-70de-b13f-42097df11715" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_019e22d7-dcd1-7567-b7e9-729ad3a37168" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_019e22d7-dcd1-7457-8675-dbae7173f7c5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e22d7-dcd1-70de-b13f-42097df11715" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_019e22d7-dcd1-7457-8675-dbae7173f7c5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_019e22d7-dcd1-74d2-ae72-0ac88fe37d40" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e22d7-dcd1-70de-b13f-42097df11715" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate_019e22d7-dcd1-74d2-ae72-0ac88fe37d40" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue_019e22d7-dcd1-78ec-80b3-63deb335c29d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e22d7-dcd1-70de-b13f-42097df11715" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue_019e22d7-dcd1-78ec-80b3-63deb335c29d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019e22d7-dcd1-7105-a770-4ae5d6bac34b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract_019e22d7-dcd1-70de-b13f-42097df11715" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019e22d7-dcd1-7105-a770-4ae5d6bac34b" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/SecuritiesScheduleofUnrealizedLossandFairValueonInvestmentsDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#SecuritiesScheduleofUnrealizedLossandFairValueonInvestmentsDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/SecuritiesScheduleofUnrealizedLossandFairValueonInvestmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-794a-9079-3131f0f34c62" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e22d7-dcd1-7434-aa7b-dfa4dd2722c3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-794a-9079-3131f0f34c62" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e22d7-dcd1-7434-aa7b-dfa4dd2722c3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-783b-ba75-0a67ab0a7f1b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e22d7-dcd1-7434-aa7b-dfa4dd2722c3" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-783b-ba75-0a67ab0a7f1b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-783b-ba75-0a67ab0a7f1b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-783b-ba75-0a67ab0a7f1b" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-783b-ba75-0a67ab0a7f1b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a86-90cc-680b6913d43c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-783b-ba75-0a67ab0a7f1b" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a86-90cc-680b6913d43c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasuryAndGovernmentMember_019e22d7-dcd1-7342-ac5c-9bd43666285e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasuryAndGovernmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a86-90cc-680b6913d43c" xlink:to="loc_us-gaap_USTreasuryAndGovernmentMember_019e22d7-dcd1-7342-ac5c-9bd43666285e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_019e22d7-dcd1-7420-b9d6-7f5b1096f862" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a86-90cc-680b6913d43c" xlink:to="loc_us-gaap_ResidentialMortgageBackedSecuritiesMember_019e22d7-dcd1-7420-b9d6-7f5b1096f862" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_019e22d7-dcd1-7ae1-acf2-0ef871089cf1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a86-90cc-680b6913d43c" xlink:to="loc_us-gaap_CommercialMortgageBackedSecuritiesMember_019e22d7-dcd1-7ae1-acf2-0ef871089cf1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e22d7-dcd1-730f-b789-37e715a5fa36" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a86-90cc-680b6913d43c" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember_019e22d7-dcd1-730f-b789-37e715a5fa36" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CollateralizedLoanObligationsMember_019e22d7-dcd1-7d1a-88e6-0b3a44873565" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CollateralizedLoanObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a86-90cc-680b6913d43c" xlink:to="loc_us-gaap_CollateralizedLoanObligationsMember_019e22d7-dcd1-7d1a-88e6-0b3a44873565" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e22d7-dcd1-7a13-b72f-0c6a58f563d6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USStatesAndPoliticalSubdivisionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a86-90cc-680b6913d43c" xlink:to="loc_us-gaap_USStatesAndPoliticalSubdivisionsMember_019e22d7-dcd1-7a13-b72f-0c6a58f563d6" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherDebtSecuritiesMember_019eb718-8cae-7c0b-8210-aeed42a2c615" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7a86-90cc-680b6913d43c" xlink:to="loc_us-gaap_OtherDebtSecuritiesMember_019eb718-8cae-7c0b-8210-aeed42a2c615" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableforSaleUnrealizedLossPositionAbstract_019e22d7-dcd1-7842-816a-8d43c973068f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableforSaleUnrealizedLossPositionAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-794a-9079-3131f0f34c62" xlink:to="loc_us-gaap_DebtSecuritiesAvailableforSaleUnrealizedLossPositionAbstract_019e22d7-dcd1-7842-816a-8d43c973068f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months_019e22d7-dcd1-7cc0-9326-561ac015c04d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtSecuritiesAvailableforSaleUnrealizedLossPositionAbstract_019e22d7-dcd1-7842-816a-8d43c973068f" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months_019e22d7-dcd1-7cc0-9326-561ac015c04d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_019e22d7-dcd1-7138-8dc0-e3d7a5881b9b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtSecuritiesAvailableforSaleUnrealizedLossPositionAbstract_019e22d7-dcd1-7842-816a-8d43c973068f" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger_019e22d7-dcd1-7138-8dc0-e3d7a5881b9b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_019e22d7-dcd1-7ddf-9689-cb252ed8c7e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtSecuritiesAvailableforSaleUnrealizedLossPositionAbstract_019e22d7-dcd1-7842-816a-8d43c973068f" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPosition_019e22d7-dcd1-7ddf-9689-cb252ed8c7e7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLossAbstract_019e22d7-dcd1-72af-99bb-1e9ce74cff91" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLossAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-794a-9079-3131f0f34c62" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLossAbstract_019e22d7-dcd1-72af-99bb-1e9ce74cff91" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_019e22d7-dcd1-72ac-aa6a-cfbfdff7003d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLossAbstract_019e22d7-dcd1-72af-99bb-1e9ce74cff91" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_019e22d7-dcd1-72ac-aa6a-cfbfdff7003d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_019e22d7-dcd1-7554-8dc8-89add6653a9b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLossAbstract_019e22d7-dcd1-72af-99bb-1e9ce74cff91" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_019e22d7-dcd1-7554-8dc8-89add6653a9b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_019e22d7-dcd1-7a0c-b1a5-daca49ad68c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLossAbstract_019e22d7-dcd1-72af-99bb-1e9ce74cff91" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_019e22d7-dcd1-7a0c-b1a5-daca49ad68c4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions_019e22d7-dcd1-7093-8884-0bcd282eeb90" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e22d7-dcd1-794a-9079-3131f0f34c62" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions_019e22d7-dcd1-7093-8884-0bcd282eeb90" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/LoansScheduleofPortfolioLoansPurchasedCreditImpairedLoansandPurchasedUnimpairedLoansDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#LoansScheduleofPortfolioLoansPurchasedCreditImpairedLoansandPurchasedUnimpairedLoansDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/LoansScheduleofPortfolioLoansPurchasedCreditImpairedLoansandPurchasedUnimpairedLoansDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e22d7-dcd1-7175-901b-a1227a67d140" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e22d7-dcd1-73c5-a31b-4927a2ef3ad5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e22d7-dcd1-7175-901b-a1227a67d140" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e22d7-dcd1-73c5-a31b-4927a2ef3ad5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7e44-aefc-6389513bab1a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e22d7-dcd1-73c5-a31b-4927a2ef3ad5" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7e44-aefc-6389513bab1a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7e44-aefc-6389513bab1a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7e44-aefc-6389513bab1a" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7e44-aefc-6389513bab1a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7d55-b6b9-a18289fbf853" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7e44-aefc-6389513bab1a" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7d55-b6b9-a18289fbf853" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-7059-9eb7-aa627efdd082" xlink:href="sbcf-20260630.xsd#sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7d55-b6b9-a18289fbf853" xlink:to="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-7059-9eb7-aa627efdd082" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-73c8-855e-db160e8b42c9" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7d55-b6b9-a18289fbf853" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-73c8-855e-db160e8b42c9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-7b60-8466-eba9e572b6e0" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7d55-b6b9-a18289fbf853" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-7b60-8466-eba9e572b6e0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-7e2c-96a1-4297631ab279" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7d55-b6b9-a18289fbf853" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-7e2c-96a1-4297631ab279" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-7809-856d-7b06e0d6632a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7d55-b6b9-a18289fbf853" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-7809-856d-7b06e0d6632a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-7fb3-b7bf-89cd23c98e56" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsumerPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7d55-b6b9-a18289fbf853" xlink:to="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-7fb3-b7bf-89cd23c98e56" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_019e22d7-dcd1-74a6-9981-d446de1e7d34" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e22d7-dcd1-73c5-a31b-4927a2ef3ad5" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_019e22d7-dcd1-74a6-9981-d446de1e7d34" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-74a6-9981-d446de1e7d34_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_019e22d7-dcd1-74a6-9981-d446de1e7d34" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-74a6-9981-d446de1e7d34_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-707e-9276-ff0f893ddeaa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_019e22d7-dcd1-74a6-9981-d446de1e7d34" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-707e-9276-ff0f893ddeaa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_PortfolioLoansMember_019e22d7-dcd1-7301-b660-490092d9a8ff" xlink:href="sbcf-20260630.xsd#sbcf_PortfolioLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-707e-9276-ff0f893ddeaa" xlink:to="loc_sbcf_PortfolioLoansMember_019e22d7-dcd1-7301-b660-490092d9a8ff" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossStatusAxis_019e22d7-dcd1-7565-916c-7af3dc1d3789" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditLossStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e22d7-dcd1-73c5-a31b-4927a2ef3ad5" xlink:to="loc_us-gaap_CreditLossStatusAxis_019e22d7-dcd1-7565-916c-7af3dc1d3789" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossStatusDomain_019e22d7-dcd1-7565-916c-7af3dc1d3789_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditLossStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditLossStatusAxis_019e22d7-dcd1-7565-916c-7af3dc1d3789" xlink:to="loc_us-gaap_CreditLossStatusDomain_019e22d7-dcd1-7565-916c-7af3dc1d3789_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossStatusDomain_019e22d7-dcd1-70e7-8423-8b401b1f0a05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditLossStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditLossStatusAxis_019e22d7-dcd1-7565-916c-7af3dc1d3789" xlink:to="loc_us-gaap_CreditLossStatusDomain_019e22d7-dcd1-70e7-8423-8b401b1f0a05" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetAcquiredAndNoCreditDeteriorationMember_019e22d7-dcd1-7caa-ad42-dd8e37dbb4ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialAssetAcquiredAndNoCreditDeteriorationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditLossStatusDomain_019e22d7-dcd1-70e7-8423-8b401b1f0a05" xlink:to="loc_us-gaap_FinancialAssetAcquiredAndNoCreditDeteriorationMember_019e22d7-dcd1-7caa-ad42-dd8e37dbb4ae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember_019e22d7-dcd1-787d-9d72-54657e13b675" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditLossStatusDomain_019e22d7-dcd1-70e7-8423-8b401b1f0a05" xlink:to="loc_us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember_019e22d7-dcd1-787d-9d72-54657e13b675" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e22d7-dcd1-7856-b468-2a49e0a29e0f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e22d7-dcd1-7175-901b-a1227a67d140" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e22d7-dcd1-7856-b468-2a49e0a29e0f" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/LoansNarrativeDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#LoansNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/LoansNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7409-91cf-f3b3d85143e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableModificationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable_019e22d7-dcd1-7918-a06d-abd59074e2d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7409-91cf-f3b3d85143e8" xlink:to="loc_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable_019e22d7-dcd1-7918-a06d-abd59074e2d5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis_019e22d7-dcd1-7d6d-aafb-ab9a17d63556" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable_019e22d7-dcd1-7918-a06d-abd59074e2d5" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis_019e22d7-dcd1-7d6d-aafb-ab9a17d63556" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_019e22d7-dcd1-7d6d-aafb-ab9a17d63556_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis_019e22d7-dcd1-7d6d-aafb-ab9a17d63556" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_019e22d7-dcd1-7d6d-aafb-ab9a17d63556_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_019e22d7-dcd1-7718-bc6e-6a6f1e1fb1c5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseAxis_019e22d7-dcd1-7d6d-aafb-ab9a17d63556" xlink:to="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_019e22d7-dcd1-7718-bc6e-6a6f1e1fb1c5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansMember_019e22d7-dcd1-7b83-b124-fcef3cdea594" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsSoldUnderAgreementsToRepurchaseTypeDomain_019e22d7-dcd1-7718-bc6e-6a6f1e1fb1c5" xlink:to="loc_us-gaap_LoansMember_019e22d7-dcd1-7b83-b124-fcef3cdea594" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredCostsCurrentAndNoncurrent_019e22d7-dcd1-7feb-b50a-9fa4200bd3de" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredCostsCurrentAndNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7409-91cf-f3b3d85143e8" xlink:to="loc_us-gaap_DeferredCostsCurrentAndNoncurrent_019e22d7-dcd1-7feb-b50a-9fa4200bd3de" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueAdjustment_019e22d7-dcd1-7a0e-be97-095fd1a62794" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueAdjustment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7409-91cf-f3b3d85143e8" xlink:to="loc_us-gaap_AssetsFairValueAdjustment_019e22d7-dcd1-7a0e-be97-095fd1a62794" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_FairValueAdjustmentPercent_019e22d7-dcd1-7ca7-9ff9-850ab7a76521" xlink:href="sbcf-20260630.xsd#sbcf_FairValueAdjustmentPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7409-91cf-f3b3d85143e8" xlink:to="loc_sbcf_FairValueAdjustmentPercent_019e22d7-dcd1-7ca7-9ff9-850ab7a76521" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAccruedInterestBeforeAllowanceForCreditLoss_019e22d7-dcd1-739e-99bf-fb049423de66" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7409-91cf-f3b3d85143e8" xlink:to="loc_us-gaap_FinancingReceivableAccruedInterestBeforeAllowanceForCreditLoss_019e22d7-dcd1-739e-99bf-fb049423de66" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_FinancingReceivableNonaccrualNoRelatedAllowanceInterestIncome_019e22d7-dcd1-7924-a708-4361d26e7792" xlink:href="sbcf-20260630.xsd#sbcf_FinancingReceivableNonaccrualNoRelatedAllowanceInterestIncome"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7409-91cf-f3b3d85143e8" xlink:to="loc_sbcf_FinancingReceivableNonaccrualNoRelatedAllowanceInterestIncome_019e22d7-dcd1-7924-a708-4361d26e7792" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/LoansScheduleofPastDueFinancingReceivablesDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#LoansScheduleofPastDueFinancingReceivablesDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/LoansScheduleofPastDueFinancingReceivablesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems_019e22d7-dcd1-76a7-b5ce-f50eb10a094c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivablesPastDueTable_019e22d7-dcd1-7877-bd0f-d1e6aa2d6a8f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFinancingReceivablesPastDueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems_019e22d7-dcd1-76a7-b5ce-f50eb10a094c" xlink:to="loc_us-gaap_ScheduleOfFinancingReceivablesPastDueTable_019e22d7-dcd1-7877-bd0f-d1e6aa2d6a8f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7766-bb5a-c99370e751cb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivablesPastDueTable_019e22d7-dcd1-7877-bd0f-d1e6aa2d6a8f" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7766-bb5a-c99370e751cb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7766-bb5a-c99370e751cb_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7766-bb5a-c99370e751cb" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7766-bb5a-c99370e751cb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7b50-a898-4bf1a8e1cd3e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7766-bb5a-c99370e751cb" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7b50-a898-4bf1a8e1cd3e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-7633-9083-abf81590280e" xlink:href="sbcf-20260630.xsd#sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7b50-a898-4bf1a8e1cd3e" xlink:to="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-7633-9083-abf81590280e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-77b4-94e0-a55e53a41e3d" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7b50-a898-4bf1a8e1cd3e" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-77b4-94e0-a55e53a41e3d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-7a59-a7ea-7a3d5cd76070" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7b50-a898-4bf1a8e1cd3e" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-7a59-a7ea-7a3d5cd76070" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-7864-9346-da03c9e64173" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7b50-a898-4bf1a8e1cd3e" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-7864-9346-da03c9e64173" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-70cf-ad25-12ec6f302261" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7b50-a898-4bf1a8e1cd3e" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-70cf-ad25-12ec6f302261" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-7198-aa8a-47488a3e0d44" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsumerPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7b50-a898-4bf1a8e1cd3e" xlink:to="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-7198-aa8a-47488a3e0d44" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_019e22d7-dcd1-72bf-8c9b-eb452573a673" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivablesPastDueTable_019e22d7-dcd1-7877-bd0f-d1e6aa2d6a8f" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_019e22d7-dcd1-72bf-8c9b-eb452573a673" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-72bf-8c9b-eb452573a673_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_019e22d7-dcd1-72bf-8c9b-eb452573a673" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-72bf-8c9b-eb452573a673_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-740e-ae92-501e5d371f71" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_019e22d7-dcd1-72bf-8c9b-eb452573a673" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-740e-ae92-501e5d371f71" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_PortfolioLoansMember_019e22d7-dcd1-7826-a42a-2f6e140b6f62" xlink:href="sbcf-20260630.xsd#sbcf_PortfolioLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-740e-ae92-501e5d371f71" xlink:to="loc_sbcf_PortfolioLoansMember_019e22d7-dcd1-7826-a42a-2f6e140b6f62" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e22d7-dcd1-7c35-8d3a-6681cd3b646c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivablesPastDueTable_019e22d7-dcd1-7877-bd0f-d1e6aa2d6a8f" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e22d7-dcd1-7c35-8d3a-6681cd3b646c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-7c35-8d3a-6681cd3b646c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e22d7-dcd1-7c35-8d3a-6681cd3b646c" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-7c35-8d3a-6681cd3b646c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-78f8-8979-c2126f72bf58" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e22d7-dcd1-7c35-8d3a-6681cd3b646c" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-78f8-8979-c2126f72bf58" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetNotPastDueMember_019e22d7-dcd1-797d-bea3-189c8cd09de5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialAssetNotPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-78f8-8979-c2126f72bf58" xlink:to="loc_us-gaap_FinancialAssetNotPastDueMember_019e22d7-dcd1-797d-bea3-189c8cd09de5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivables30To59DaysPastDueMember_019e22d7-dcd1-73a0-ad6a-8275b90bd1a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivables30To59DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-78f8-8979-c2126f72bf58" xlink:to="loc_us-gaap_FinancingReceivables30To59DaysPastDueMember_019e22d7-dcd1-73a0-ad6a-8275b90bd1a4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivables60To89DaysPastDueMember_019e22d7-dcd1-7536-a6e3-153a73b41439" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivables60To89DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-78f8-8979-c2126f72bf58" xlink:to="loc_us-gaap_FinancingReceivables60To89DaysPastDueMember_019e22d7-dcd1-7536-a6e3-153a73b41439" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember_019e22d7-dcd1-7350-8fb2-c582ce704ca8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-78f8-8979-c2126f72bf58" xlink:to="loc_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember_019e22d7-dcd1-7350-8fb2-c582ce704ca8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossStatusAxis_019e22d7-dcd1-79d2-aa5e-b16fe87d7e09" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditLossStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivablesPastDueTable_019e22d7-dcd1-7877-bd0f-d1e6aa2d6a8f" xlink:to="loc_us-gaap_CreditLossStatusAxis_019e22d7-dcd1-79d2-aa5e-b16fe87d7e09" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossStatusDomain_019e22d7-dcd1-79d2-aa5e-b16fe87d7e09_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditLossStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditLossStatusAxis_019e22d7-dcd1-79d2-aa5e-b16fe87d7e09" xlink:to="loc_us-gaap_CreditLossStatusDomain_019e22d7-dcd1-79d2-aa5e-b16fe87d7e09_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossStatusDomain_019e22d7-dcd1-7a4b-a6b8-8de9fba7e9c3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditLossStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditLossStatusAxis_019e22d7-dcd1-79d2-aa5e-b16fe87d7e09" xlink:to="loc_us-gaap_CreditLossStatusDomain_019e22d7-dcd1-7a4b-a6b8-8de9fba7e9c3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetAcquiredAndNoCreditDeteriorationMember_019e22d7-dcd1-7378-afd4-5f1215c6376e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialAssetAcquiredAndNoCreditDeteriorationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditLossStatusDomain_019e22d7-dcd1-7a4b-a6b8-8de9fba7e9c3" xlink:to="loc_us-gaap_FinancialAssetAcquiredAndNoCreditDeteriorationMember_019e22d7-dcd1-7378-afd4-5f1215c6376e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember_019e22d7-dcd1-7f1b-8ad3-dd7c69cb5c6e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditLossStatusDomain_019e22d7-dcd1-7a4b-a6b8-8de9fba7e9c3" xlink:to="loc_us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember_019e22d7-dcd1-7f1b-8ad3-dd7c69cb5c6e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e22d7-dcd1-71d2-8b84-a3cff60d07de" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems_019e22d7-dcd1-76a7-b5ce-f50eb10a094c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e22d7-dcd1-71d2-8b84-a3cff60d07de" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual_019e22d7-dcd1-75ac-a7e1-567119a41c7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentPastDueLineItems_019e22d7-dcd1-76a7-b5ce-f50eb10a094c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual_019e22d7-dcd1-75ac-a7e1-567119a41c7c" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/LoansScheduleofNonaccrualLoansbyLoanCategoryDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#LoansScheduleofNonaccrualLoansbyLoanCategoryDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/LoansScheduleofNonaccrualLoansbyLoanCategoryDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableNonaccrualStatusLineItems_019e22d7-dcd1-7788-9ce4-3fb9c9aa029b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableNonaccrualStatusLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableNonaccrualTable_019e22d7-dcd1-7efb-97ec-84e6d584fdfe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableNonaccrualTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FinancingReceivableNonaccrualStatusLineItems_019e22d7-dcd1-7788-9ce4-3fb9c9aa029b" xlink:to="loc_us-gaap_FinancingReceivableNonaccrualTable_019e22d7-dcd1-7efb-97ec-84e6d584fdfe" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7966-9704-164cbc78e8b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FinancingReceivableNonaccrualTable_019e22d7-dcd1-7efb-97ec-84e6d584fdfe" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7966-9704-164cbc78e8b6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7966-9704-164cbc78e8b6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7966-9704-164cbc78e8b6" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7966-9704-164cbc78e8b6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7ad3-ba3f-de453e2d9cba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7966-9704-164cbc78e8b6" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7ad3-ba3f-de453e2d9cba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-74e0-98a3-237ac5e9b3d7" xlink:href="sbcf-20260630.xsd#sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7ad3-ba3f-de453e2d9cba" xlink:to="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-74e0-98a3-237ac5e9b3d7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-7e00-8515-c8be08b63bd6" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7ad3-ba3f-de453e2d9cba" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-7e00-8515-c8be08b63bd6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-7f92-9e05-99c31bef47d9" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7ad3-ba3f-de453e2d9cba" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-7f92-9e05-99c31bef47d9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-717c-809f-cca5089886c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7ad3-ba3f-de453e2d9cba" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-717c-809f-cca5089886c2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-77f1-98ad-09711bef9271" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7ad3-ba3f-de453e2d9cba" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-77f1-98ad-09711bef9271" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-7afa-a95b-212d3c114a86" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsumerPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7ad3-ba3f-de453e2d9cba" xlink:to="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-7afa-a95b-212d3c114a86" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance_019e22d7-dcd1-7420-9009-b4788ca33f86" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableNonaccrualStatusLineItems_019e22d7-dcd1-7788-9ce4-3fb9c9aa029b" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance_019e22d7-dcd1-7420-9009-b4788ca33f86" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_FinancingReceivableExcludingAccruedInterestNonaccrualWithAllowanceForCreditLosses_019e22d7-dcd1-76dd-a6f8-4568fdbb4124" xlink:href="sbcf-20260630.xsd#sbcf_FinancingReceivableExcludingAccruedInterestNonaccrualWithAllowanceForCreditLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableNonaccrualStatusLineItems_019e22d7-dcd1-7788-9ce4-3fb9c9aa029b" xlink:to="loc_sbcf_FinancingReceivableExcludingAccruedInterestNonaccrualWithAllowanceForCreditLosses_019e22d7-dcd1-76dd-a6f8-4568fdbb4124" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual_019e22d7-dcd1-707f-8256-3f9b3c8d5a63" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableNonaccrualStatusLineItems_019e22d7-dcd1-7788-9ce4-3fb9c9aa029b" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual_019e22d7-dcd1-707f-8256-3f9b3c8d5a63" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/LoansScheduleofRiskCategoriesofLoansbyClassofLoansDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#LoansScheduleofRiskCategoriesofLoansbyClassofLoansDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/LoansScheduleofRiskCategoriesofLoansbyClassofLoansDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableRecordedInvestmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_019e22d7-dcd1-7fb5-8b99-5b0b18484318" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_019e22d7-dcd1-7fb5-8b99-5b0b18484318" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-71dd-ab17-098473eff90b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_019e22d7-dcd1-7fb5-8b99-5b0b18484318" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-71dd-ab17-098473eff90b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-71dd-ab17-098473eff90b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-71dd-ab17-098473eff90b" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-71dd-ab17-098473eff90b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7322-9335-12fdaaed80f3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-71dd-ab17-098473eff90b" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7322-9335-12fdaaed80f3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-7c3c-9409-ad5a0281c2de" xlink:href="sbcf-20260630.xsd#sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7322-9335-12fdaaed80f3" xlink:to="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-7c3c-9409-ad5a0281c2de" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-71bf-9636-61214d7e362b" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7322-9335-12fdaaed80f3" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-71bf-9636-61214d7e362b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-7ba5-b8a7-7c88679fb83c" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7322-9335-12fdaaed80f3" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-7ba5-b8a7-7c88679fb83c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-7e3c-9d42-87a4ed97cdd3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7322-9335-12fdaaed80f3" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-7e3c-9d42-87a4ed97cdd3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-7c2d-a90b-2c7434e6fc92" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7322-9335-12fdaaed80f3" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-7c2d-a90b-2c7434e6fc92" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-7f28-9f49-f29327427bf2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsumerPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7322-9335-12fdaaed80f3" xlink:to="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-7f28-9f49-f29327427bf2" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentAxis_019e22d7-dcd1-759a-878e-4ef5e5274e41" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_019e22d7-dcd1-7fb5-8b99-5b0b18484318" xlink:to="loc_us-gaap_InternalCreditAssessmentAxis_019e22d7-dcd1-759a-878e-4ef5e5274e41" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_019e22d7-dcd1-759a-878e-4ef5e5274e41_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_019e22d7-dcd1-759a-878e-4ef5e5274e41" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_019e22d7-dcd1-759a-878e-4ef5e5274e41_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InternalCreditAssessmentDomain_019e22d7-dcd1-74e7-8154-80990ba97aec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InternalCreditAssessmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_InternalCreditAssessmentAxis_019e22d7-dcd1-759a-878e-4ef5e5274e41" xlink:to="loc_us-gaap_InternalCreditAssessmentDomain_019e22d7-dcd1-74e7-8154-80990ba97aec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PassMember_019e22d7-dcd1-7b30-9bd6-25b6730ac1a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PassMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e22d7-dcd1-74e7-8154-80990ba97aec" xlink:to="loc_us-gaap_PassMember_019e22d7-dcd1-7b30-9bd6-25b6730ac1a7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SpecialMentionMember_019e22d7-dcd1-7295-a45b-46c24ea97f40" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SpecialMentionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e22d7-dcd1-74e7-8154-80990ba97aec" xlink:to="loc_us-gaap_SpecialMentionMember_019e22d7-dcd1-7295-a45b-46c24ea97f40" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubstandardMember_019e22d7-dcd1-7cee-b28f-cf25dda9136d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubstandardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e22d7-dcd1-74e7-8154-80990ba97aec" xlink:to="loc_us-gaap_SubstandardMember_019e22d7-dcd1-7cee-b28f-cf25dda9136d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DoubtfulMember_019e22d7-dcd1-7746-9ecc-898113f84679" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DoubtfulMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InternalCreditAssessmentDomain_019e22d7-dcd1-74e7-8154-80990ba97aec" xlink:to="loc_us-gaap_DoubtfulMember_019e22d7-dcd1-7746-9ecc-898113f84679" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear_019e22d7-dcd1-78dd-b1aa-abfc5db4ebb2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYear_019e22d7-dcd1-78dd-b1aa-abfc5db4ebb2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear_019e22d7-dcd1-7732-bd36-a05119382ef8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYear_019e22d7-dcd1-7732-bd36-a05119382ef8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear_019e22d7-dcd1-781c-a9b3-ce92311b2262" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYear_019e22d7-dcd1-781c-a9b3-ce92311b2262" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear_019e22d7-dcd1-7100-86e9-bc9d1303b001" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYear_019e22d7-dcd1-7100-86e9-bc9d1303b001" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear_019e22d7-dcd1-797b-8d4c-83256ddb8bae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYear_019e22d7-dcd1-797b-8d4c-83256ddb8bae" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear_019e22d7-dcd1-7a06-81fc-e6a7c86b6137" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYear_019e22d7-dcd1-7a06-81fc-e6a7c86b6137" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestRevolving_019e22d7-dcd1-7219-bc9f-ca1c97cb8275" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestRevolving"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestRevolving_019e22d7-dcd1-7219-bc9f-ca1c97cb8275" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoan_019e22d7-dcd1-76cf-a3c0-f2e9345ec1c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoan_019e22d7-dcd1-76cf-a3c0-f2e9345ec1c9" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e22d7-dcd1-7b53-b03c-196e6c5b86db" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss_019e22d7-dcd1-7b53-b03c-196e6c5b86db" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYearWriteoff_019e22d7-dcd1-75ee-8e0d-b3ff066748a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYearWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearOneOriginatedCurrentFiscalYearWriteoff_019e22d7-dcd1-75ee-8e0d-b3ff066748a7" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff_019e22d7-dcd1-7e63-a057-eb727c7c4887" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearTwoOriginatedFiscalYearBeforeCurrentFiscalYearWriteoff_019e22d7-dcd1-7e63-a057-eb727c7c4887" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff_019e22d7-dcd1-7e12-a610-1b3f0a21e76d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearThreeOriginatedTwoYearsBeforeCurrentFiscalYearWriteoff_019e22d7-dcd1-7e12-a610-1b3f0a21e76d" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff_019e22d7-dcd1-7cd0-99ae-a650b840d76d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFourOriginatedThreeYearsBeforeCurrentFiscalYearWriteoff_019e22d7-dcd1-7cd0-99ae-a650b840d76d" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff_019e22d7-dcd1-74f6-b742-f67988fd0fb9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestYearFiveOriginatedFourYearsBeforeCurrentFiscalYearWriteoff_019e22d7-dcd1-74f6-b742-f67988fd0fb9" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff_019e22d7-dcd1-7836-8534-b99d94819d71" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestOriginatedMoreThanFiveYearsBeforeCurrentFiscalYearWriteoff_019e22d7-dcd1-7836-8534-b99d94819d71" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingWriteoff_019e22d7-dcd1-74e3-ad05-d4d860c8aa25" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingWriteoff_019e22d7-dcd1-74e3-ad05-d4d860c8aa25" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoanWriteoff_019e22d7-dcd1-7e15-96cc-58de4f1e7975" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoanWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestRevolvingConvertedToTermLoanWriteoff_019e22d7-dcd1-7e15-96cc-58de4f1e7975" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff_019e22d7-dcd1-7233-ab89-7d8b092870db" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentLineItems_019e22d7-dcd1-7a99-b03e-4726f5669e2c" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff_019e22d7-dcd1-7233-ab89-7d8b092870db" xlink:type="arc" order="17"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/LoansScheduleofTroubledBorrowerModificationsDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#LoansScheduleofTroubledBorrowerModificationsDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/LoansScheduleofTroubledBorrowerModificationsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7835-a412-d6a55f929158" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableModificationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable_019e22d7-dcd1-74e9-8056-36219536f8c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7835-a412-d6a55f929158" xlink:to="loc_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable_019e22d7-dcd1-74e9-8056-36219536f8c9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7f4e-9467-e76fee1fe50d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable_019e22d7-dcd1-74e9-8056-36219536f8c9" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7f4e-9467-e76fee1fe50d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7f4e-9467-e76fee1fe50d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7f4e-9467-e76fee1fe50d" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7f4e-9467-e76fee1fe50d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-76ea-b6f1-546b573c9fa8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7f4e-9467-e76fee1fe50d" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-76ea-b6f1-546b573c9fa8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-7dc0-a7ca-f1d570a174fa" xlink:href="sbcf-20260630.xsd#sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-76ea-b6f1-546b573c9fa8" xlink:to="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-7dc0-a7ca-f1d570a174fa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-7a31-8b03-fc52fcca4c63" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-76ea-b6f1-546b573c9fa8" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-7a31-8b03-fc52fcca4c63" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-735e-bc31-283fa9d2df92" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-76ea-b6f1-546b573c9fa8" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-735e-bc31-283fa9d2df92" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-7227-95ea-92651c98a2bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-76ea-b6f1-546b573c9fa8" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-7227-95ea-92651c98a2bb" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-7ade-85a2-b9e72ad908fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-76ea-b6f1-546b573c9fa8" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-7ade-85a2-b9e72ad908fa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-739e-9804-12c4dc944d02" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsumerPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-76ea-b6f1-546b573c9fa8" xlink:to="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-739e-9804-12c4dc944d02" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanRestructuringModificationAxis_019e22d7-dcd1-7096-ad83-7fb7c0e871fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoanRestructuringModificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable_019e22d7-dcd1-74e9-8056-36219536f8c9" xlink:to="loc_us-gaap_LoanRestructuringModificationAxis_019e22d7-dcd1-7096-ad83-7fb7c0e871fa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanRestructuringModificationDomain_019e22d7-dcd1-7096-ad83-7fb7c0e871fa_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoanRestructuringModificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LoanRestructuringModificationAxis_019e22d7-dcd1-7096-ad83-7fb7c0e871fa" xlink:to="loc_us-gaap_LoanRestructuringModificationDomain_019e22d7-dcd1-7096-ad83-7fb7c0e871fa_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoanRestructuringModificationDomain_019e22d7-dcd1-727b-8ece-6bbcb009bbe2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoanRestructuringModificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LoanRestructuringModificationAxis_019e22d7-dcd1-7096-ad83-7fb7c0e871fa" xlink:to="loc_us-gaap_LoanRestructuringModificationDomain_019e22d7-dcd1-727b-8ece-6bbcb009bbe2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ExtendedMaturityAndInterestRateReductionMember_019e22d7-dcd1-71c0-a118-942ffbc03b37" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExtendedMaturityAndInterestRateReductionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanRestructuringModificationDomain_019e22d7-dcd1-727b-8ece-6bbcb009bbe2" xlink:to="loc_us-gaap_ExtendedMaturityAndInterestRateReductionMember_019e22d7-dcd1-71c0-a118-942ffbc03b37" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ExtendedMaturityAndPaymentDeferralMember_019e22d7-dcd1-75eb-aff2-2384adb33eeb" xlink:href="sbcf-20260630.xsd#sbcf_ExtendedMaturityAndPaymentDeferralMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LoanRestructuringModificationDomain_019e22d7-dcd1-727b-8ece-6bbcb009bbe2" xlink:to="loc_sbcf_ExtendedMaturityAndPaymentDeferralMember_019e22d7-dcd1-75eb-aff2-2384adb33eeb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e22d7-dcd1-78e0-8b4f-52cf08cc0a0c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableTroubledDebtRestructuringsTable_019e22d7-dcd1-74e9-8056-36219536f8c9" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e22d7-dcd1-78e0-8b4f-52cf08cc0a0c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-78e0-8b4f-52cf08cc0a0c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e22d7-dcd1-78e0-8b4f-52cf08cc0a0c" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-78e0-8b4f-52cf08cc0a0c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-7125-953b-e3ee7cc8fc49" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueAxis_019e22d7-dcd1-78e0-8b4f-52cf08cc0a0c" xlink:to="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-7125-953b-e3ee7cc8fc49" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetNotPastDueMember_019e22d7-dcd1-7524-bb11-387b495588b1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialAssetNotPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-7125-953b-e3ee7cc8fc49" xlink:to="loc_us-gaap_FinancialAssetNotPastDueMember_019e22d7-dcd1-7524-bb11-387b495588b1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivables30To59DaysPastDueMember_019e22d7-dcd1-7ba8-941a-c2a1ee703c47" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivables30To59DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-7125-953b-e3ee7cc8fc49" xlink:to="loc_us-gaap_FinancingReceivables30To59DaysPastDueMember_019e22d7-dcd1-7ba8-941a-c2a1ee703c47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivables60To89DaysPastDueMember_019e22d7-dcd1-7c50-9d45-dcab0416bbba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivables60To89DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-7125-953b-e3ee7cc8fc49" xlink:to="loc_us-gaap_FinancingReceivables60To89DaysPastDueMember_019e22d7-dcd1-7c50-9d45-dcab0416bbba" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember_019e22d7-dcd1-76db-acd5-5d9fea52265b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablesPeriodPastDueDomain_019e22d7-dcd1-7125-953b-e3ee7cc8fc49" xlink:to="loc_us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember_019e22d7-dcd1-76db-acd5-5d9fea52265b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPeriod_019e22d7-dcd1-713b-80d9-5d0afeded0b9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7835-a412-d6a55f929158" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPeriod_019e22d7-dcd1-713b-80d9-5d0afeded0b9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableModificationToTotalFinancingReceivablesExcludingAccruedInterestPercent_019e22d7-dcd1-7c1e-b7fe-6aea41f81024" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableModificationToTotalFinancingReceivablesExcludingAccruedInterestPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7835-a412-d6a55f929158" xlink:to="loc_us-gaap_FinancingReceivableModificationToTotalFinancingReceivablesExcludingAccruedInterestPercent_019e22d7-dcd1-7c1e-b7fe-6aea41f81024" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_FinancingReceivableExcludingAccruedInterestModifiedNonaccrual_019e22d7-dcd1-714a-99d1-0c0adbf51134" xlink:href="sbcf-20260630.xsd#sbcf_FinancingReceivableExcludingAccruedInterestModifiedNonaccrual"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7835-a412-d6a55f929158" xlink:to="loc_sbcf_FinancingReceivableExcludingAccruedInterestModifiedNonaccrual_019e22d7-dcd1-714a-99d1-0c0adbf51134" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPast12Months_019e22d7-dcd1-77c2-8c4b-7292fdd12b37" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPast12Months"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableModificationsLineItems_019e22d7-dcd1-7835-a412-d6a55f929158" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestModifiedPast12Months_019e22d7-dcd1-77c2-8c4b-7292fdd12b37" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/AllowanceforCreditLossesScheduleofActivityinAllowanceforCreditLossesDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#AllowanceforCreditLossesScheduleofActivityinAllowanceforCreditLossesDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/AllowanceforCreditLossesScheduleofActivityinAllowanceforCreditLossesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e22d7-dcd1-7bdd-889e-a3b0d79d7d3b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_019e22d7-dcd1-7dda-99cb-94b602cb8251" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e22d7-dcd1-7bdd-889e-a3b0d79d7d3b" xlink:to="loc_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_019e22d7-dcd1-7dda-99cb-94b602cb8251" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7bd0-89cc-12dfa30e6002" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableAllowanceForCreditLossesTable_019e22d7-dcd1-7dda-99cb-94b602cb8251" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7bd0-89cc-12dfa30e6002" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7bd0-89cc-12dfa30e6002_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7bd0-89cc-12dfa30e6002" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-7bd0-89cc-12dfa30e6002_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-78cd-844d-88dbe856d02a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePortfolioSegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentAxis_019e22d7-dcd1-7bd0-89cc-12dfa30e6002" xlink:to="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-78cd-844d-88dbe856d02a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-71c3-ae7f-18263c8d2ea7" xlink:href="sbcf-20260630.xsd#sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-78cd-844d-88dbe856d02a" xlink:to="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-71c3-ae7f-18263c8d2ea7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-778c-8506-81c0a0f38110" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-78cd-844d-88dbe856d02a" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-778c-8506-81c0a0f38110" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-77ea-bfcf-d684a224b96f" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-78cd-844d-88dbe856d02a" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-77ea-bfcf-d684a224b96f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-7b74-b715-16cbca45fea8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-78cd-844d-88dbe856d02a" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-7b74-b715-16cbca45fea8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-709c-8fb6-fa26fcb5555a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-78cd-844d-88dbe856d02a" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-709c-8fb6-fa26fcb5555a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-76b0-b13a-4c4ab3bf6913" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsumerPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivablePortfolioSegmentDomain_019e22d7-dcd1-78cd-844d-88dbe856d02a" xlink:to="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-76b0-b13a-4c4ab3bf6913" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_019e22d7-dcd1-7ba7-9ddf-8a9301d7f806" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems_019e22d7-dcd1-7bdd-889e-a3b0d79d7d3b" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_019e22d7-dcd1-7ba7-9ddf-8a9301d7f806" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_019e22d7-dcd1-7d42-970c-cbfa87eac8e3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_019e22d7-dcd1-7ba7-9ddf-8a9301d7f806" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_019e22d7-dcd1-7d42-970c-cbfa87eac8e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal_019e22d7-dcd1-7541-915e-ed963dbdb206" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_019e22d7-dcd1-7ba7-9ddf-8a9301d7f806" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestCreditLossExpenseReversal_019e22d7-dcd1-7541-915e-ed963dbdb206" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff_019e22d7-dcd1-72ca-b4a6-d687546a92f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_019e22d7-dcd1-7ba7-9ddf-8a9301d7f806" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossWriteoff_019e22d7-dcd1-72ca-b4a6-d687546a92f9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery_019e22d7-dcd1-7821-869f-d46262b7cfcb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward_019e22d7-dcd1-7ba7-9ddf-8a9301d7f806" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAllowanceForCreditLossRecovery_019e22d7-dcd1-7821-869f-d46262b7cfcb" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_019e22d7-dcd1-72ec-8549-b0e82d886603" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/DerivativesNarrativeDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#DerivativesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/DerivativesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7e44-bb30-adf4da39a3fd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019e22d7-dcd1-75d4-b094-64cc8d796861" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7e44-bb30-adf4da39a3fd" xlink:to="loc_us-gaap_DerivativeTable_019e22d7-dcd1-75d4-b094-64cc8d796861" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e22d7-dcd1-75f1-8c24-26358dbc6030" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e22d7-dcd1-75d4-b094-64cc8d796861" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e22d7-dcd1-75f1-8c24-26358dbc6030" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-75f1-8c24-26358dbc6030_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e22d7-dcd1-75f1-8c24-26358dbc6030" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-75f1-8c24-26358dbc6030_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-7678-88fe-8a2cec3a5d70" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e22d7-dcd1-75f1-8c24-26358dbc6030" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-7678-88fe-8a2cec3a5d70" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateCapMember_019e3dda-326d-776f-8d5e-a788f5527ab9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateCapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-7678-88fe-8a2cec3a5d70" xlink:to="loc_us-gaap_InterestRateCapMember_019e3dda-326d-776f-8d5e-a788f5527ab9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_InterestRateCapOneMember_019e3dda-326d-7fbd-ba3c-fc69628fd81f" xlink:href="sbcf-20260630.xsd#sbcf_InterestRateCapOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCapMember_019e3dda-326d-776f-8d5e-a788f5527ab9" xlink:to="loc_sbcf_InterestRateCapOneMember_019e3dda-326d-7fbd-ba3c-fc69628fd81f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_InterestRateCapTwoMember_019e3dda-326d-7f19-9c33-ba6234e99472" xlink:href="sbcf-20260630.xsd#sbcf_InterestRateCapTwoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCapMember_019e3dda-326d-776f-8d5e-a788f5527ab9" xlink:to="loc_sbcf_InterestRateCapTwoMember_019e3dda-326d-7f19-9c33-ba6234e99472" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_InterestRateCapThreeMember_019e3dda-326d-72fb-9012-e040992e8086" xlink:href="sbcf-20260630.xsd#sbcf_InterestRateCapThreeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateCapMember_019e3dda-326d-776f-8d5e-a788f5527ab9" xlink:to="loc_sbcf_InterestRateCapThreeMember_019e3dda-326d-72fb-9012-e040992e8086" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_SecuritiesInterestRateSwapMember_019e22d7-dcd1-7c40-b2a1-7c0415c9518e" xlink:href="sbcf-20260630.xsd#sbcf_SecuritiesInterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-7678-88fe-8a2cec3a5d70" xlink:to="loc_sbcf_SecuritiesInterestRateSwapMember_019e22d7-dcd1-7c40-b2a1-7c0415c9518e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ResidentialMortgageInterestRateSwapMember_019e22d7-dcd1-7e60-8056-094e3f31f038" xlink:href="sbcf-20260630.xsd#sbcf_ResidentialMortgageInterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-7678-88fe-8a2cec3a5d70" xlink:to="loc_sbcf_ResidentialMortgageInterestRateSwapMember_019e22d7-dcd1-7e60-8056-094e3f31f038" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateLockCommitmentsMember_019e3df8-ef17-7bfc-b397-698d492aca06" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateLockCommitmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-7678-88fe-8a2cec3a5d70" xlink:to="loc_us-gaap_InterestRateLockCommitmentsMember_019e3df8-ef17-7bfc-b397-698d492aca06" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e3dda-326d-7859-a973-3d8e6f1b0db6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e22d7-dcd1-75d4-b094-64cc8d796861" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e3dda-326d-7859-a973-3d8e6f1b0db6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019e3dda-326d-7859-a973-3d8e6f1b0db6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e3dda-326d-7859-a973-3d8e6f1b0db6" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019e3dda-326d-7859-a973-3d8e6f1b0db6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019e3dda-326d-7004-ae65-4d03598a7ce5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e3dda-326d-7859-a973-3d8e6f1b0db6" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019e3dda-326d-7004-ae65-4d03598a7ce5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_019e3dda-326d-7a27-b06c-7ed22065f94f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019e3dda-326d-7004-ae65-4d03598a7ce5" xlink:to="loc_us-gaap_CashFlowHedgingMember_019e3dda-326d-7a27-b06c-7ed22065f94f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNumberOfInstrumentsHeld_019e3ddd-f2c9-7b13-b91f-039282dfa1e4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNumberOfInstrumentsHeld"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7e44-bb30-adf4da39a3fd" xlink:to="loc_us-gaap_DerivativeNumberOfInstrumentsHeld_019e3ddd-f2c9-7b13-b91f-039282dfa1e4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019e3dda-326d-74b0-a04a-60f6126cee7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7e44-bb30-adf4da39a3fd" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019e3dda-326d-74b0-a04a-60f6126cee7c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019e3dda-326d-7f88-b94a-f74ad17b312b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7e44-bb30-adf4da39a3fd" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax_019e3dda-326d-7f88-b94a-f74ad17b312b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019e3dda-326d-7af1-a09d-ed0c4c413960" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7e44-bb30-adf4da39a3fd" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax_019e3dda-326d-7af1-a09d-ed0c4c413960" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths_019e3dda-326d-731d-8a9e-5abbc53610bf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7e44-bb30-adf4da39a3fd" xlink:to="loc_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths_019e3dda-326d-731d-8a9e-5abbc53610bf" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_OtherComprehensiveIncomeLossFairValueHedgeGainLossBeforeReclassificationAndTax_019e22d7-dcd1-7836-a286-9f094b6423cb" xlink:href="sbcf-20260630.xsd#sbcf_OtherComprehensiveIncomeLossFairValueHedgeGainLossBeforeReclassificationAndTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7e44-bb30-adf4da39a3fd" xlink:to="loc_sbcf_OtherComprehensiveIncomeLossFairValueHedgeGainLossBeforeReclassificationAndTax_019e22d7-dcd1-7836-a286-9f094b6423cb" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_OtherComprehensiveIncomeLossFairValueHedgeGainLossReclassificationBeforeTax_019e22d7-dcd1-7ba3-ac24-9c28cb9295ee" xlink:href="sbcf-20260630.xsd#sbcf_OtherComprehensiveIncomeLossFairValueHedgeGainLossReclassificationBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7e44-bb30-adf4da39a3fd" xlink:to="loc_sbcf_OtherComprehensiveIncomeLossFairValueHedgeGainLossReclassificationBeforeTax_019e22d7-dcd1-7ba3-ac24-9c28cb9295ee" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnDerivativeInstrumentsNetPretax_019e22d7-dcd1-7dbd-991a-ba58b2df9822" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnDerivativeInstrumentsNetPretax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7e44-bb30-adf4da39a3fd" xlink:to="loc_us-gaap_GainLossOnDerivativeInstrumentsNetPretax_019e22d7-dcd1-7dbd-991a-ba58b2df9822" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/DerivativesScheduleofDerivativeInstrumentsDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#DerivativesScheduleofDerivativeInstrumentsDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/DerivativesScheduleofDerivativeInstrumentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e22d7-dcd1-7eb5-a6e4-163717c34716" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019e22d7-dcd1-7690-b98e-c139b585c34e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e22d7-dcd1-7eb5-a6e4-163717c34716" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019e22d7-dcd1-7690-b98e-c139b585c34e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e22d7-dcd1-7671-933d-7de749bf4643" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019e22d7-dcd1-7690-b98e-c139b585c34e" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e22d7-dcd1-7671-933d-7de749bf4643" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-7671-933d-7de749bf4643_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e22d7-dcd1-7671-933d-7de749bf4643" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-7671-933d-7de749bf4643_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e22d7-dcd1-7671-933d-7de749bf4643" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_019e22d7-dcd1-7293-b456-a02ed0e08c56" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_us-gaap_InterestRateContractMember_019e22d7-dcd1-7293-b456-a02ed0e08c56" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ResidentialMortgageInterestRateSwapMember_019e22d7-dcd1-7ba2-a2ed-65c106d2bb94" xlink:href="sbcf-20260630.xsd#sbcf_ResidentialMortgageInterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_sbcf_ResidentialMortgageInterestRateSwapMember_019e22d7-dcd1-7ba2-a2ed-65c106d2bb94" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateCapMember_019e22de-737c-711d-bb78-56b5c863389b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateCapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_us-gaap_InterestRateCapMember_019e22de-737c-711d-bb78-56b5c863389b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateLockCommitmentsMember_019e22df-7575-725d-99c0-e73b1bf40a65" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateLockCommitmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_us-gaap_InterestRateLockCommitmentsMember_019e22df-7575-725d-99c0-e73b1bf40a65" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ForwardTBAMortgageBackedSecuritiesMember_019e22e0-b79a-7a57-a746-ed57ab4f863a" xlink:href="sbcf-20260630.xsd#sbcf_ForwardTBAMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_sbcf_ForwardTBAMortgageBackedSecuritiesMember_019e22e0-b79a-7a57-a746-ed57ab4f863a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ForwardLoanSaleCommitmentMember_019e22e0-fc8e-7c61-8a28-3ff8d0073447" xlink:href="sbcf-20260630.xsd#sbcf_ForwardLoanSaleCommitmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_sbcf_ForwardLoanSaleCommitmentMember_019e22e0-fc8e-7c61-8a28-3ff8d0073447" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_InterestRateContractsRiskParticipationAgreementsMember_019e22d7-dcd1-78ab-bd9c-8539d8b9b406" xlink:href="sbcf-20260630.xsd#sbcf_InterestRateContractsRiskParticipationAgreementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_sbcf_InterestRateContractsRiskParticipationAgreementsMember_019e22d7-dcd1-78ab-bd9c-8539d8b9b406" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfFinancialPositionLocationBalanceAxis_019e22d7-dcd1-7307-a7ba-d20dce87ace8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfFinancialPositionLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019e22d7-dcd1-7690-b98e-c139b585c34e" xlink:to="loc_us-gaap_StatementOfFinancialPositionLocationBalanceAxis_019e22d7-dcd1-7307-a7ba-d20dce87ace8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e22d7-dcd1-7987-8fa0-9ebc05da5959" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019e22d7-dcd1-7690-b98e-c139b585c34e" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e22d7-dcd1-7987-8fa0-9ebc05da5959" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019e22d7-dcd1-7987-8fa0-9ebc05da5959_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e22d7-dcd1-7987-8fa0-9ebc05da5959" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019e22d7-dcd1-7987-8fa0-9ebc05da5959_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019e22d7-dcd1-7b1d-9371-af610e41aa5c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e22d7-dcd1-7987-8fa0-9ebc05da5959" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019e22d7-dcd1-7b1d-9371-af610e41aa5c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueHedgingMember_019e22d7-dcd1-7ff2-a726-c1ea82cd4dd6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019e22d7-dcd1-7b1d-9371-af610e41aa5c" xlink:to="loc_us-gaap_FairValueHedgingMember_019e22d7-dcd1-7ff2-a726-c1ea82cd4dd6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_019e22e0-3a62-7a26-8af8-60238a642ced" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019e22d7-dcd1-7b1d-9371-af610e41aa5c" xlink:to="loc_us-gaap_CashFlowHedgingMember_019e22e0-3a62-7a26-8af8-60238a642ced" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019e22d7-dcd1-7cba-8c00-d430a4db78e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e22d7-dcd1-7eb5-a6e4-163717c34716" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019e22d7-dcd1-7cba-8c00-d430a4db78e7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019e22d7-dcd1-763c-a60b-81cdcc859ab7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e22d7-dcd1-7eb5-a6e4-163717c34716" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019e22d7-dcd1-763c-a60b-81cdcc859ab7" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/DerivativesScheduleofDerivativeInstrumentsDetails_1" xlink:type="simple" xlink:href="sbcf-20260630.xsd#DerivativesScheduleofDerivativeInstrumentsDetails_1"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/DerivativesScheduleofDerivativeInstrumentsDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e22d7-dcd1-7eb5-a6e4-163717c34716" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019e22d7-dcd1-7690-b98e-c139b585c34e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e22d7-dcd1-7eb5-a6e4-163717c34716" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019e22d7-dcd1-7690-b98e-c139b585c34e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e22d7-dcd1-7671-933d-7de749bf4643" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019e22d7-dcd1-7690-b98e-c139b585c34e" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e22d7-dcd1-7671-933d-7de749bf4643" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-7671-933d-7de749bf4643_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e22d7-dcd1-7671-933d-7de749bf4643" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-7671-933d-7de749bf4643_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e22d7-dcd1-7671-933d-7de749bf4643" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateContractMember_019e22d7-dcd1-7293-b456-a02ed0e08c56" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_us-gaap_InterestRateContractMember_019e22d7-dcd1-7293-b456-a02ed0e08c56" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ResidentialMortgageInterestRateSwapMember_019e22d7-dcd1-7ba2-a2ed-65c106d2bb94" xlink:href="sbcf-20260630.xsd#sbcf_ResidentialMortgageInterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_sbcf_ResidentialMortgageInterestRateSwapMember_019e22d7-dcd1-7ba2-a2ed-65c106d2bb94" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateCapMember_019e22de-737c-711d-bb78-56b5c863389b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateCapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_us-gaap_InterestRateCapMember_019e22de-737c-711d-bb78-56b5c863389b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateLockCommitmentsMember_019e22df-7575-725d-99c0-e73b1bf40a65" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateLockCommitmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_us-gaap_InterestRateLockCommitmentsMember_019e22df-7575-725d-99c0-e73b1bf40a65" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ForwardTBAMortgageBackedSecuritiesMember_019e22e0-b79a-7a57-a746-ed57ab4f863a" xlink:href="sbcf-20260630.xsd#sbcf_ForwardTBAMortgageBackedSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_sbcf_ForwardTBAMortgageBackedSecuritiesMember_019e22e0-b79a-7a57-a746-ed57ab4f863a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ForwardLoanSaleCommitmentMember_019e22e0-fc8e-7c61-8a28-3ff8d0073447" xlink:href="sbcf-20260630.xsd#sbcf_ForwardLoanSaleCommitmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_sbcf_ForwardLoanSaleCommitmentMember_019e22e0-fc8e-7c61-8a28-3ff8d0073447" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_InterestRateContractsRiskParticipationAgreementsMember_019e22d7-dcd1-78ab-bd9c-8539d8b9b406" xlink:href="sbcf-20260630.xsd#sbcf_InterestRateContractsRiskParticipationAgreementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e22d7-dcd1-74db-940d-3e3a7dbb7048" xlink:to="loc_sbcf_InterestRateContractsRiskParticipationAgreementsMember_019e22d7-dcd1-78ab-bd9c-8539d8b9b406" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e22d7-dcd1-7987-8fa0-9ebc05da5959" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_019e22d7-dcd1-7690-b98e-c139b585c34e" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e22d7-dcd1-7987-8fa0-9ebc05da5959" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019e22d7-dcd1-7987-8fa0-9ebc05da5959_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e22d7-dcd1-7987-8fa0-9ebc05da5959" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019e22d7-dcd1-7987-8fa0-9ebc05da5959_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019e22d7-dcd1-7b1d-9371-af610e41aa5c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e22d7-dcd1-7987-8fa0-9ebc05da5959" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019e22d7-dcd1-7b1d-9371-af610e41aa5c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueHedgingMember_019e22d7-dcd1-7ff2-a726-c1ea82cd4dd6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019e22d7-dcd1-7b1d-9371-af610e41aa5c" xlink:to="loc_us-gaap_FairValueHedgingMember_019e22d7-dcd1-7ff2-a726-c1ea82cd4dd6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashFlowHedgingMember_019e22e0-3a62-7a26-8af8-60238a642ced" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashFlowHedgingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019e22d7-dcd1-7b1d-9371-af610e41aa5c" xlink:to="loc_us-gaap_CashFlowHedgingMember_019e22e0-3a62-7a26-8af8-60238a642ced" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019e22d7-dcd1-7cba-8c00-d430a4db78e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e22d7-dcd1-7eb5-a6e4-163717c34716" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019e22d7-dcd1-7cba-8c00-d430a4db78e7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019e22d7-dcd1-763c-a60b-81cdcc859ab7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFairValueOfDerivativeNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_019e22d7-dcd1-7eb5-a6e4-163717c34716" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeNet_019e22d7-dcd1-763c-a60b-81cdcc859ab7" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/DerivativesScheduleofFairValueHedgesDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#DerivativesScheduleofFairValueHedgesDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/DerivativesScheduleofFairValueHedgesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7322-ae63-00128cbcf87c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019e22d7-dcd1-727d-8cad-91c262e428c7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7322-ae63-00128cbcf87c" xlink:to="loc_us-gaap_DerivativeTable_019e22d7-dcd1-727d-8cad-91c262e428c7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByAssetClassAxis_019e22d7-dcd1-7af7-ad3b-6628eda82f46" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByAssetClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e22d7-dcd1-727d-8cad-91c262e428c7" xlink:to="loc_us-gaap_FairValueByAssetClassAxis_019e22d7-dcd1-7af7-ad3b-6628eda82f46" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e22d7-dcd1-7af7-ad3b-6628eda82f46_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_019e22d7-dcd1-7af7-ad3b-6628eda82f46" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e22d7-dcd1-7af7-ad3b-6628eda82f46_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e22d7-dcd1-7ca8-ac3a-b49ddf9e7aa3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_019e22d7-dcd1-7af7-ad3b-6628eda82f46" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e22d7-dcd1-7ca8-ac3a-b49ddf9e7aa3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableMember_019e22d7-dcd1-7c68-a4d5-0e9300bda119" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e22d7-dcd1-7ca8-ac3a-b49ddf9e7aa3" xlink:to="loc_us-gaap_LoansReceivableMember_019e22d7-dcd1-7c68-a4d5-0e9300bda119" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedge_019e22d7-dcd1-7d94-9802-5732996439f0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedge"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7322-ae63-00128cbcf87c" xlink:to="loc_us-gaap_HedgedAssetFairValueHedge_019e22d7-dcd1-7d94-9802-5732996439f0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedgeCumulativeIncreaseDecrease_019e22d7-dcd1-75e5-ae63-0410c23e34ce" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedgeCumulativeIncreaseDecrease"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7322-ae63-00128cbcf87c" xlink:to="loc_us-gaap_HedgedAssetFairValueHedgeCumulativeIncreaseDecrease_019e22d7-dcd1-75e5-ae63-0410c23e34ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrepayableFinancialAssetClosedPortfolioLastOfLayerAmortizedCost_019e22d7-dcd1-7baf-96b4-0d674acd267a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepayableFinancialAssetClosedPortfolioLastOfLayerAmortizedCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7322-ae63-00128cbcf87c" xlink:to="loc_us-gaap_PrepayableFinancialAssetClosedPortfolioLastOfLayerAmortizedCost_019e22d7-dcd1-7baf-96b4-0d674acd267a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgedAssetFairValueHedgeLastOfLayerAmount_019e22d7-dcd1-78d1-b8c0-d9ff0f8270d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgedAssetFairValueHedgeLastOfLayerAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e22d7-dcd1-7322-ae63-00128cbcf87c" xlink:to="loc_us-gaap_HedgedAssetFairValueHedgeLastOfLayerAmount_019e22d7-dcd1-78d1-b8c0-d9ff0f8270d5" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/SecuritiesSoldUnderAgreementstoRepurchaseDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#SecuritiesSoldUnderAgreementstoRepurchaseDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/SecuritiesSoldUnderAgreementstoRepurchaseDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesFinancingTransactionLineItems_019e22d7-dcd1-7be8-96fd-26beefd40fc5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesFinancingTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesFinancingTransactionTable_019e22d7-dcd1-7778-a6a7-d1115be24660" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesFinancingTransactionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_019e22d7-dcd1-7be8-96fd-26beefd40fc5" xlink:to="loc_us-gaap_SecuritiesFinancingTransactionTable_019e22d7-dcd1-7778-a6a7-d1115be24660" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7182-af14-235d074f74cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionTable_019e22d7-dcd1-7778-a6a7-d1115be24660" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7182-af14-235d074f74cd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7182-af14-235d074f74cd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7182-af14-235d074f74cd" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7182-af14-235d074f74cd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7f35-a398-ac79566d3d44" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-7182-af14-235d074f74cd" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7f35-a398-ac79566d3d44" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e22d7-dcd1-7b5f-9c35-4899e9096cec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7f35-a398-ac79566d3d44" xlink:to="loc_us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember_019e22d7-dcd1-7b5f-9c35-4899e9096cec" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_019e22d7-dcd1-7aef-b533-9866587defb5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementBasisAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionTable_019e22d7-dcd1-7778-a6a7-d1115be24660" xlink:to="loc_us-gaap_FairValueByMeasurementBasisAxis_019e22d7-dcd1-7aef-b533-9866587defb5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e22d7-dcd1-7aef-b533-9866587defb5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_019e22d7-dcd1-7aef-b533-9866587defb5" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e22d7-dcd1-7aef-b533-9866587defb5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e22d7-dcd1-7b22-b445-de09be7d1cf4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueDisclosureItemAmountsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_019e22d7-dcd1-7aef-b533-9866587defb5" xlink:to="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e22d7-dcd1-7b22-b445-de09be7d1cf4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e22d7-dcd1-7d17-96e7-c0d3d7efc8fd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e22d7-dcd1-7b22-b445-de09be7d1cf4" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e22d7-dcd1-7d17-96e7-c0d3d7efc8fd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_019e22d7-dcd1-7d56-9e2d-3f828096c4e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e22d7-dcd1-7d17-96e7-c0d3d7efc8fd" xlink:to="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_019e22d7-dcd1-7d56-9e2d-3f828096c4e7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PledgedStatusAxis_019e22d7-dcd1-7818-85f6-9018c059539e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgedStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionTable_019e22d7-dcd1-7778-a6a7-d1115be24660" xlink:to="loc_us-gaap_PledgedStatusAxis_019e22d7-dcd1-7818-85f6-9018c059539e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PledgedStatusDomain_019e22d7-dcd1-7818-85f6-9018c059539e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgedStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PledgedStatusAxis_019e22d7-dcd1-7818-85f6-9018c059539e" xlink:to="loc_us-gaap_PledgedStatusDomain_019e22d7-dcd1-7818-85f6-9018c059539e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PledgedStatusDomain_019e22d7-dcd1-7a70-b654-93d8aaffa9b8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PledgedStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PledgedStatusAxis_019e22d7-dcd1-7818-85f6-9018c059539e" xlink:to="loc_us-gaap_PledgedStatusDomain_019e22d7-dcd1-7a70-b654-93d8aaffa9b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetPledgedAsCollateralMember_019e22d7-dcd1-72a8-8261-352aab60ca4d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetPledgedAsCollateralMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PledgedStatusDomain_019e22d7-dcd1-7a70-b654-93d8aaffa9b8" xlink:to="loc_us-gaap_AssetPledgedAsCollateralMember_019e22d7-dcd1-72a8-8261-352aab60ca4d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_FairValueOfPledgedSecuritiesOvernightAndContinuousAbstract_019e22d7-dcd1-73a5-93c1-d38bf135d68f" xlink:href="sbcf-20260630.xsd#sbcf_FairValueOfPledgedSecuritiesOvernightAndContinuousAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SecuritiesFinancingTransactionLineItems_019e22d7-dcd1-7be8-96fd-26beefd40fc5" xlink:to="loc_sbcf_FairValueOfPledgedSecuritiesOvernightAndContinuousAbstract_019e22d7-dcd1-73a5-93c1-d38bf135d68f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentsOwnedAtFairValue_019e22d7-dcd1-7279-a1cf-537e0c5f62d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentsOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_sbcf_FairValueOfPledgedSecuritiesOvernightAndContinuousAbstract_019e22d7-dcd1-73a5-93c1-d38bf135d68f" xlink:to="loc_us-gaap_FinancialInstrumentsOwnedAtFairValue_019e22d7-dcd1-7279-a1cf-537e0c5f62d3" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/FairValueScheduleofFairValueofAssetsMeasuredonRecurringandNonrecurringBasisDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#FairValueScheduleofFairValueofAssetsMeasuredonRecurringandNonrecurringBasisDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/FairValueScheduleofFairValueofAssetsMeasuredonRecurringandNonrecurringBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-7ff7-a784-a6ecbe051ce8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-793c-b712-e7a6e0b4c5ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-7ff7-a784-a6ecbe051ce8" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-793c-b712-e7a6e0b4c5ac" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e22d7-dcd1-7ddf-b8f0-c32dc024d3bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-793c-b712-e7a6e0b4c5ac" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e22d7-dcd1-7ddf-b8f0-c32dc024d3bc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7ddf-b8f0-c32dc024d3bc_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e22d7-dcd1-7ddf-b8f0-c32dc024d3bc" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7ddf-b8f0-c32dc024d3bc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7ba0-82e5-a33adb571a26" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e22d7-dcd1-7ddf-b8f0-c32dc024d3bc" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7ba0-82e5-a33adb571a26" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_019e22d7-dcd1-7ecb-a4ac-daa2df728bc1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7ba0-82e5-a33adb571a26" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_019e22d7-dcd1-7ecb-a4ac-daa2df728bc1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019e22d7-dcd1-776f-a5f8-76336d822e90" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7ba0-82e5-a33adb571a26" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019e22d7-dcd1-776f-a5f8-76336d822e90" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019e22d7-dcd1-7fb0-8b2d-16b647ca9746" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7ba0-82e5-a33adb571a26" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019e22d7-dcd1-7fb0-8b2d-16b647ca9746" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e22d7-dcd1-7df8-a973-de0f70ec7a5d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-793c-b712-e7a6e0b4c5ac" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e22d7-dcd1-7df8-a973-de0f70ec7a5d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e22d7-dcd1-7df8-a973-de0f70ec7a5d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e22d7-dcd1-7df8-a973-de0f70ec7a5d" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e22d7-dcd1-7df8-a973-de0f70ec7a5d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e22d7-dcd1-744f-960c-2d9ed98992ea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e22d7-dcd1-7df8-a973-de0f70ec7a5d" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e22d7-dcd1-744f-960c-2d9ed98992ea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_019e22d7-dcd1-73f6-9ddd-5a6fe50a9c2c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e22d7-dcd1-744f-960c-2d9ed98992ea" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_019e22d7-dcd1-73f6-9ddd-5a6fe50a9c2c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsNonrecurringMember_019e22d7-dcd1-76cd-b47c-8922268c5c25" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsNonrecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e22d7-dcd1-744f-960c-2d9ed98992ea" xlink:to="loc_us-gaap_FairValueMeasurementsNonrecurringMember_019e22d7-dcd1-76cd-b47c-8922268c5c25" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-76c1-9104-8527cc8e5568" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-7ff7-a784-a6ecbe051ce8" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-76c1-9104-8527cc8e5568" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019e22d7-dcd1-7624-9032-ec240dab2620" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-76c1-9104-8527cc8e5568" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterest_019e22d7-dcd1-7624-9032-ec240dab2620" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_019e22d7-dcd1-7d49-bdfa-b77c2af915cb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-76c1-9104-8527cc8e5568" xlink:to="loc_us-gaap_DerivativeAssets_019e22d7-dcd1-7d49-bdfa-b77c2af915cb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansHeldForSaleFairValueDisclosure_019e22d7-dcd1-7657-9223-13705781aab4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansHeldForSaleFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-76c1-9104-8527cc8e5568" xlink:to="loc_us-gaap_LoansHeldForSaleFairValueDisclosure_019e22d7-dcd1-7657-9223-13705781aab4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherRealEstate_019e22d7-dcd1-7fad-af93-baa940112cea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherRealEstate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-76c1-9104-8527cc8e5568" xlink:to="loc_us-gaap_OtherRealEstate_019e22d7-dcd1-7fad-af93-baa940112cea" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquitySecuritiesFvNi_019e22d7-dcd1-7aeb-b3db-2b1d3f7c0d83" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquitySecuritiesFvNi"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-76c1-9104-8527cc8e5568" xlink:to="loc_us-gaap_EquitySecuritiesFvNi_019e22d7-dcd1-7aeb-b3db-2b1d3f7c0d83" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServicingAssetAtFairValueAmount_019e3e86-ab71-706e-ba64-f8d81aabc396" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ServicingAssetAtFairValueAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-76c1-9104-8527cc8e5568" xlink:to="loc_us-gaap_ServicingAssetAtFairValueAmount_019e3e86-ab71-706e-ba64-f8d81aabc396" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e22d7-dcd1-7d02-969e-133922f78612" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-7ff7-a784-a6ecbe051ce8" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e22d7-dcd1-7d02-969e-133922f78612" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_019e22d7-dcd1-7f00-a2d6-844e75e330a2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e22d7-dcd1-7d02-969e-133922f78612" xlink:to="loc_us-gaap_DerivativeLiabilities_019e22d7-dcd1-7f00-a2d6-844e75e330a2" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/FairValueNarrativeDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#FairValueNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/FairValueNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-7341-a79c-8a9f2efa1a5b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-7acf-bc2c-808d6208d45b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-7341-a79c-8a9f2efa1a5b" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-7acf-bc2c-808d6208d45b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e9354-4045-7f5d-bb67-1ed29501a2f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-7acf-bc2c-808d6208d45b" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e9354-4045-7f5d-bb67-1ed29501a2f8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e9354-4045-7f5d-bb67-1ed29501a2f8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e9354-4045-7f5d-bb67-1ed29501a2f8" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e9354-4045-7f5d-bb67-1ed29501a2f8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e9354-4045-7eed-9a97-101896b80c62" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e9354-4045-7f5d-bb67-1ed29501a2f8" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e9354-4045-7eed-9a97-101896b80c62" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateLockCommitmentsMember_019e9354-4045-79f7-a568-0135f196c41c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateLockCommitmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e9354-4045-7eed-9a97-101896b80c62" xlink:to="loc_us-gaap_InterestRateLockCommitmentsMember_019e9354-4045-79f7-a568-0135f196c41c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ForwardLoanSaleCommitmentMember_019e9354-4045-7c44-8b41-d82fe43f51fe" xlink:href="sbcf-20260630.xsd#sbcf_ForwardLoanSaleCommitmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e9354-4045-7eed-9a97-101896b80c62" xlink:to="loc_sbcf_ForwardLoanSaleCommitmentMember_019e9354-4045-7c44-8b41-d82fe43f51fe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeAxis_019e9354-4045-7c2b-a2e7-2469ea4045a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-7acf-bc2c-808d6208d45b" xlink:to="loc_us-gaap_MeasurementInputTypeAxis_019e9354-4045-7c2b-a2e7-2469ea4045a4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_019e9354-4045-7c2b-a2e7-2469ea4045a4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_019e9354-4045-7c2b-a2e7-2469ea4045a4" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_019e9354-4045-7c2b-a2e7-2469ea4045a4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MeasurementInputTypeDomain_019e9354-4045-722f-9e7b-d817bdb22dbc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_MeasurementInputTypeAxis_019e9354-4045-7c2b-a2e7-2469ea4045a4" xlink:to="loc_us-gaap_MeasurementInputTypeDomain_019e9354-4045-722f-9e7b-d817bdb22dbc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_MeasurementInputWeightedAveragePullThroughRateMember_019e9354-4045-7d87-af7c-86ad49759164" xlink:href="sbcf-20260630.xsd#sbcf_MeasurementInputWeightedAveragePullThroughRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e9354-4045-722f-9e7b-d817bdb22dbc" xlink:to="loc_sbcf_MeasurementInputWeightedAveragePullThroughRateMember_019e9354-4045-7d87-af7c-86ad49759164" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_MeasurementInputWeightedAverageCurrentReferencePriceMember_019e9354-4045-709c-a4c0-d589b42042dc" xlink:href="sbcf-20260630.xsd#sbcf_MeasurementInputWeightedAverageCurrentReferencePriceMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MeasurementInputTypeDomain_019e9354-4045-722f-9e7b-d817bdb22dbc" xlink:to="loc_sbcf_MeasurementInputWeightedAverageCurrentReferencePriceMember_019e9354-4045-709c-a4c0-d589b42042dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_019e22d7-dcd1-72f1-9281-dcc4daeb0d60" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-7acf-bc2c-808d6208d45b" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_019e22d7-dcd1-72f1-9281-dcc4daeb0d60" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-72f1-9281-dcc4daeb0d60_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_019e22d7-dcd1-72f1-9281-dcc4daeb0d60" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-72f1-9281-dcc4daeb0d60_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-7694-acb3-22bbac944323" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis_019e22d7-dcd1-72f1-9281-dcc4daeb0d60" xlink:to="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-7694-acb3-22bbac944323" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CollateralDependentRealEstateLoansMember_019e22d7-dcd1-78f5-b0cd-886795eab28a" xlink:href="sbcf-20260630.xsd#sbcf_CollateralDependentRealEstateLoansMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FinancingReceivableRecordedInvestmentClassOfFinancingReceivableDomain_019e22d7-dcd1-7694-acb3-22bbac944323" xlink:to="loc_sbcf_CollateralDependentRealEstateLoansMember_019e22d7-dcd1-78f5-b0cd-886795eab28a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e22d7-dcd1-7651-b2be-eaf15d712bd4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-7acf-bc2c-808d6208d45b" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e22d7-dcd1-7651-b2be-eaf15d712bd4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7651-b2be-eaf15d712bd4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e22d7-dcd1-7651-b2be-eaf15d712bd4" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7651-b2be-eaf15d712bd4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7f2e-a8f3-2090170fa981" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e22d7-dcd1-7651-b2be-eaf15d712bd4" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7f2e-a8f3-2090170fa981" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember_019e22d7-dcd1-7510-afb6-aa7e20164657" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7f2e-a8f3-2090170fa981" xlink:to="loc_us-gaap_FairValueMeasuredAtNetAssetValuePerShareMember_019e22d7-dcd1-7510-afb6-aa7e20164657" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019e22d7-dcd1-7f83-a096-eae0059726d1" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-7acf-bc2c-808d6208d45b" xlink:to="loc_srt_RangeAxis_019e22d7-dcd1-7f83-a096-eae0059726d1" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e22d7-dcd1-7f83-a096-eae0059726d1_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019e22d7-dcd1-7f83-a096-eae0059726d1" xlink:to="loc_srt_RangeMember_019e22d7-dcd1-7f83-a096-eae0059726d1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e22d7-dcd1-7b75-85fe-e7dd09a871b7" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019e22d7-dcd1-7f83-a096-eae0059726d1" xlink:to="loc_srt_RangeMember_019e22d7-dcd1-7b75-85fe-e7dd09a871b7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019e22d7-dcd1-779b-8db7-869eb10f51cf" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e22d7-dcd1-7b75-85fe-e7dd09a871b7" xlink:to="loc_srt_MinimumMember_019e22d7-dcd1-779b-8db7-869eb10f51cf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019e22d7-dcd1-7325-bd81-379d5021cf6c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e22d7-dcd1-7b75-85fe-e7dd09a871b7" xlink:to="loc_srt_MaximumMember_019e22d7-dcd1-7325-bd81-379d5021cf6c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetMeasurementInput_019e9354-4045-7361-b730-cee2dcebdfdf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssetMeasurementInput"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-7341-a79c-8a9f2efa1a5b" xlink:to="loc_us-gaap_DerivativeAssetMeasurementInput_019e9354-4045-7361-b730-cee2dcebdfdf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LoansReceivableFairValueDisclosure_019e22d7-dcd1-7443-84da-8f0d62fc1a74" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansReceivableFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-7341-a79c-8a9f2efa1a5b" xlink:to="loc_us-gaap_LoansReceivableFairValueDisclosure_019e22d7-dcd1-7443-84da-8f0d62fc1a74" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AlternativeInvestment_019e22d7-dcd1-7b59-a416-94005499de3b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AlternativeInvestment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-7341-a79c-8a9f2efa1a5b" xlink:to="loc_us-gaap_AlternativeInvestment_019e22d7-dcd1-7b59-a416-94005499de3b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLiquidatingInvestmentRemainingPeriod1_019e22d7-dcd1-709a-82f6-f56f257f3a3b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLiquidatingInvestmentRemainingPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-7341-a79c-8a9f2efa1a5b" xlink:to="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareLiquidatingInvestmentRemainingPeriod1_019e22d7-dcd1-709a-82f6-f56f257f3a3b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments_019e22d7-dcd1-7981-8c13-ff24844e9e16" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-7341-a79c-8a9f2efa1a5b" xlink:to="loc_us-gaap_FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments_019e22d7-dcd1-7981-8c13-ff24844e9e16" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/FairValueScheduleofCarryingAmountandFairValueofOtherSignificantFinancialInstrumentsNotMeasuredonaRecurringBasisDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#FairValueScheduleofCarryingAmountandFairValueofOtherSignificantFinancialInstrumentsNotMeasuredonaRecurringBasisDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/FairValueScheduleofCarryingAmountandFairValueofOtherSignificantFinancialInstrumentsNotMeasuredonaRecurringBasisDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-76f7-9c45-8b3ca2ae3309" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-7e75-ada6-d49496d52007" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-76f7-9c45-8b3ca2ae3309" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-7e75-ada6-d49496d52007" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_019e22d7-dcd1-7e89-b192-352b09a5b3c7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementBasisAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-7e75-ada6-d49496d52007" xlink:to="loc_us-gaap_FairValueByMeasurementBasisAxis_019e22d7-dcd1-7e89-b192-352b09a5b3c7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e22d7-dcd1-7e89-b192-352b09a5b3c7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_019e22d7-dcd1-7e89-b192-352b09a5b3c7" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e22d7-dcd1-7e89-b192-352b09a5b3c7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e22d7-dcd1-7bd8-8afe-8198c12a4edf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueDisclosureItemAmountsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_019e22d7-dcd1-7e89-b192-352b09a5b3c7" xlink:to="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e22d7-dcd1-7bd8-8afe-8198c12a4edf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e22d7-dcd1-71c8-9e8f-a67219856267" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e22d7-dcd1-7bd8-8afe-8198c12a4edf" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e22d7-dcd1-71c8-9e8f-a67219856267" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_019e22d7-dcd1-72da-8642-4626ec317fd0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e22d7-dcd1-7bd8-8afe-8198c12a4edf" xlink:to="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_019e22d7-dcd1-72da-8642-4626ec317fd0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e22d7-dcd1-75d0-89ff-9f791d56cec7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e22d7-dcd1-7e75-ada6-d49496d52007" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e22d7-dcd1-75d0-89ff-9f791d56cec7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-75d0-89ff-9f791d56cec7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e22d7-dcd1-75d0-89ff-9f791d56cec7" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-75d0-89ff-9f791d56cec7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7339-aff3-56f1b40f8b1d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e22d7-dcd1-75d0-89ff-9f791d56cec7" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7339-aff3-56f1b40f8b1d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_019e22d7-dcd1-798a-9964-d4dbca0f7f8f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7339-aff3-56f1b40f8b1d" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_019e22d7-dcd1-798a-9964-d4dbca0f7f8f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019e22d7-dcd1-70d2-971c-70b73e0e37f5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7339-aff3-56f1b40f8b1d" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019e22d7-dcd1-70d2-971c-70b73e0e37f5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019e22d7-dcd1-780a-8056-96d8a70e3186" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e22d7-dcd1-7339-aff3-56f1b40f8b1d" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019e22d7-dcd1-780a-8056-96d8a70e3186" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-7b15-baec-ae971f4cbac9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-76f7-9c45-8b3ca2ae3309" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-7b15-baec-ae971f4cbac9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7705-b462-03c7eaf581e4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-7b15-baec-ae971f4cbac9" xlink:to="loc_us-gaap_DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7705-b462-03c7eaf581e4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_TimeDepositsWithOtherBanks_019e22d7-dcd1-7bc4-9201-d4cf4481cf01" xlink:href="sbcf-20260630.xsd#sbcf_TimeDepositsWithOtherBanks"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-7b15-baec-ae971f4cbac9" xlink:to="loc_sbcf_TimeDepositsWithOtherBanks_019e22d7-dcd1-7bc4-9201-d4cf4481cf01" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7fbd-adf7-eeb199644c0f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e22d7-dcd1-7b15-baec-ae971f4cbac9" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-7fbd-adf7-eeb199644c0f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e22d7-dcd1-783e-9653-dd7d311067ce" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e22d7-dcd1-76f7-9c45-8b3ca2ae3309" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e22d7-dcd1-783e-9653-dd7d311067ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepositsFairValueDisclosure_019e22d7-dcd1-7661-bd64-2a12993c7aa6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepositsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e22d7-dcd1-783e-9653-dd7d311067ce" xlink:to="loc_us-gaap_DepositsFairValueDisclosure_019e22d7-dcd1-7661-bd64-2a12993c7aa6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure_019e22d7-dcd1-75a2-9bec-8c542bdf2a30" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e22d7-dcd1-783e-9653-dd7d311067ce" xlink:to="loc_us-gaap_FederalHomeLoanBankBorrowingsFairValueDisclosure_019e22d7-dcd1-75a2-9bec-8c542bdf2a30" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations_019e22d7-dcd1-73fd-b886-c298a2329760" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e22d7-dcd1-783e-9653-dd7d311067ce" xlink:to="loc_us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations_019e22d7-dcd1-73fd-b886-c298a2329760" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/BusinessCombinationsNarrativeDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#BusinessCombinationsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/BusinessCombinationsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7daf-abf9-3b1bc95529f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7daf-abf9-3b1bc95529f7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019e3e16-3ee3-746f-adba-24b2bd4df383" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7daf-abf9-3b1bc95529f7" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019e3e16-3ee3-746f-adba-24b2bd4df383" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e3e16-3ee3-746f-adba-24b2bd4df383_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e3e16-3ee3-746f-adba-24b2bd4df383" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e3e16-3ee3-746f-adba-24b2bd4df383_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e3e16-3ee3-732b-9abc-5aa65c0bf9f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e3e16-3ee3-746f-adba-24b2bd4df383" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e3e16-3ee3-732b-9abc-5aa65c0bf9f7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_VillagesBancorporationIncMember_019e3e16-3ee3-70f7-b3b3-52a2dbbd0b2f" xlink:href="sbcf-20260630.xsd#sbcf_VillagesBancorporationIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e3e16-3ee3-732b-9abc-5aa65c0bf9f7" xlink:to="loc_sbcf_VillagesBancorporationIncMember_019e3e16-3ee3-70f7-b3b3-52a2dbbd0b2f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_HeartlandBancsharesIncMember_019e3e16-a180-7a2d-92fa-3d7276479e4b" xlink:href="sbcf-20260630.xsd#sbcf_HeartlandBancsharesIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e3e16-3ee3-732b-9abc-5aa65c0bf9f7" xlink:to="loc_sbcf_HeartlandBancsharesIncMember_019e3e16-a180-7a2d-92fa-3d7276479e4b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossStatusAxis_019e3e16-a180-7a93-84df-a0b8c377c9b8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditLossStatusAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7daf-abf9-3b1bc95529f7" xlink:to="loc_us-gaap_CreditLossStatusAxis_019e3e16-a180-7a93-84df-a0b8c377c9b8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossStatusDomain_019e3e16-a180-7a93-84df-a0b8c377c9b8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditLossStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditLossStatusAxis_019e3e16-a180-7a93-84df-a0b8c377c9b8" xlink:to="loc_us-gaap_CreditLossStatusDomain_019e3e16-a180-7a93-84df-a0b8c377c9b8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditLossStatusDomain_019e3e16-a180-78d6-adf1-4f28ccb5765e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditLossStatusDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditLossStatusAxis_019e3e16-a180-7a93-84df-a0b8c377c9b8" xlink:to="loc_us-gaap_CreditLossStatusDomain_019e3e16-a180-78d6-adf1-4f28ccb5765e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialAssetAcquiredAndNoCreditDeteriorationMember_019e3e16-a180-74bc-a244-3498240a4004" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialAssetAcquiredAndNoCreditDeteriorationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditLossStatusDomain_019e3e16-a180-78d6-adf1-4f28ccb5765e" xlink:to="loc_us-gaap_FinancialAssetAcquiredAndNoCreditDeteriorationMember_019e3e16-a180-74bc-a244-3498240a4004" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessAcquisitionNumberOfBranches_019e3e16-3ee3-7b62-b1ec-f22126de91fb" xlink:href="sbcf-20260630.xsd#sbcf_BusinessAcquisitionNumberOfBranches"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_sbcf_BusinessAcquisitionNumberOfBranches_019e3e16-3ee3-7b62-b1ec-f22126de91fb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_019e3e16-3ee3-7506-be58-47c26d9084aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_019e3e16-3ee3-7506-be58-47c26d9084aa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableCashPaidPerAcquireeShare_019e3e16-3ee3-782b-96b7-d6062624710d" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableCashPaidPerAcquireeShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_sbcf_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableCashPaidPerAcquireeShare_019e3e16-3ee3-782b-96b7-d6062624710d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationExchangeRatio_019e3e16-3ee3-700a-9784-382172e0ed54" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationExchangeRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_sbcf_BusinessCombinationExchangeRatio_019e3e16-3ee3-700a-9784-382172e0ed54" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableCashPaidPerAcquireeSharePercentage_019e3e16-3ee3-7a90-bec5-7daf409dafcf" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableCashPaidPerAcquireeSharePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_sbcf_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableCashPaidPerAcquireeSharePercentage_019e3e16-3ee3-7a90-bec5-7daf409dafcf" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableEntitySharesIssuedPerAcquireeSharePercentage_019e3e16-3ee3-740f-8fc1-90a156b7bbf9" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableEntitySharesIssuedPerAcquireeSharePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_sbcf_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableEntitySharesIssuedPerAcquireeSharePercentage_019e3e16-3ee3-740f-8fc1-90a156b7bbf9" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationCommonStockThresholdOfOutstandingStockThatWillReceivePreferredStock_019e3e16-3ee3-7456-85a8-c3690f34c882" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationCommonStockThresholdOfOutstandingStockThatWillReceivePreferredStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_sbcf_BusinessCombinationCommonStockThresholdOfOutstandingStockThatWillReceivePreferredStock_019e3e16-3ee3-7456-85a8-c3690f34c882" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_019e3e16-3ee3-7de7-a370-4efc1c1dbb88" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_019e3e16-3ee3-7de7-a370-4efc1c1dbb88" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_019e3e16-61d5-7297-8e34-d796ef872066" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_us-gaap_Goodwill_019e3e16-61d5-7297-8e34-d796ef872066" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_019e3e16-a180-71fa-a861-4b849ec3d8fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest_019e3e16-a180-71fa-a861-4b849ec3d8fa" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivableExcludingAccruedInterestPurchasedWithCreditDeteriorationAllowanceForCreditLossAtAcquisitionDate_019e3e16-a180-7163-96e2-9bc87b4dedd8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivableExcludingAccruedInterestPurchasedWithCreditDeteriorationAllowanceForCreditLossAtAcquisitionDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_us-gaap_FinancingReceivableExcludingAccruedInterestPurchasedWithCreditDeteriorationAllowanceForCreditLossAtAcquisitionDate_019e3e16-a180-7163-96e2-9bc87b4dedd8" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_019e3e16-a180-7be5-9f72-46d0a4652e43" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_019e3e16-a180-7be5-9f72-46d0a4652e43" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtPurchasePrice_019e3e16-f591-73eb-b81f-de4c43bf099e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtPurchasePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtPurchasePrice_019e3e16-f591-73eb-b81f-de4c43bf099e" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtParValue_019e3e16-f591-73c4-9112-447be39ab868" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtParValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e3e16-3ee3-733c-b884-19752cc938de" xlink:to="loc_us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtParValue_019e3e16-f591-73c4-9112-447be39ab868" xlink:type="arc" order="13"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/BusinessCombinationsScheduleofPurchasePriceDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#BusinessCombinationsScheduleofPurchasePriceDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/BusinessCombinationsScheduleofPurchasePriceDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-72fc-88bc-4fd5fb3e7885" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-72fc-88bc-4fd5fb3e7885" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-76bf-8f12-cd4368c67c99" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-72fc-88bc-4fd5fb3e7885" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-76bf-8f12-cd4368c67c99" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-76bf-8f12-cd4368c67c99_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-76bf-8f12-cd4368c67c99" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-76bf-8f12-cd4368c67c99_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7179-b2a8-ea79ef0e41ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-76bf-8f12-cd4368c67c99" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7179-b2a8-ea79ef0e41ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_VillagesBancorporationIncMember_019e22d7-dcd1-7a81-8615-eb3eb18b7a35" xlink:href="sbcf-20260630.xsd#sbcf_VillagesBancorporationIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7179-b2a8-ea79ef0e41ac" xlink:to="loc_sbcf_VillagesBancorporationIncMember_019e22d7-dcd1-7a81-8615-eb3eb18b7a35" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_HeartlandBancsharesIncMember_019e22d7-dcd1-7d03-96d5-d6d946916d87" xlink:href="sbcf-20260630.xsd#sbcf_HeartlandBancsharesIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7179-b2a8-ea79ef0e41ac" xlink:to="loc_sbcf_HeartlandBancsharesIncMember_019e22d7-dcd1-7d03-96d5-d6d946916d87" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019e22d7-dcd1-7ad2-b0e6-dabb114af43c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-72fc-88bc-4fd5fb3e7885" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019e22d7-dcd1-7ad2-b0e6-dabb114af43c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e22d7-dcd1-7ad2-b0e6-dabb114af43c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e22d7-dcd1-7ad2-b0e6-dabb114af43c" xlink:to="loc_us-gaap_ClassOfStockDomain_019e22d7-dcd1-7ad2-b0e6-dabb114af43c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e22d7-dcd1-7f61-b8f2-78c7fe56705a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e22d7-dcd1-7ad2-b0e6-dabb114af43c" xlink:to="loc_us-gaap_ClassOfStockDomain_019e22d7-dcd1-7f61-b8f2-78c7fe56705a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019e22d7-dcd1-7438-b29b-1b93ab053450" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e22d7-dcd1-7f61-b8f2-78c7fe56705a" xlink:to="loc_us-gaap_CommonStockMember_019e22d7-dcd1-7438-b29b-1b93ab053450" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockMember_019e22d7-dcd1-7ed0-9778-8f826381cc7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e22d7-dcd1-7f61-b8f2-78c7fe56705a" xlink:to="loc_us-gaap_PreferredStockMember_019e22d7-dcd1-7ed0-9778-8f826381cc7c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationNumberOfCommonStockSharesAcquiredReceivedStock_019e22d7-dcd1-7a86-ab77-f22ed457a671" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationNumberOfCommonStockSharesAcquiredReceivedStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:to="loc_sbcf_BusinessCombinationNumberOfCommonStockSharesAcquiredReceivedStock_019e22d7-dcd1-7a86-ab77-f22ed457a671" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationExchangeRatio_019e22d7-dcd1-72eb-8040-b13f6e511864" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationExchangeRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:to="loc_sbcf_BusinessCombinationExchangeRatio_019e22d7-dcd1-72eb-8040-b13f6e511864" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_019e22d7-dcd1-76e3-8506-20014028d62e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:to="loc_us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_019e22d7-dcd1-76e3-8506-20014028d62e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionSharePrice_019e22d7-dcd1-735b-9a27-241b419fa0b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionSharePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:to="loc_us-gaap_BusinessAcquisitionSharePrice_019e22d7-dcd1-735b-9a27-241b419fa0b6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_019e3e2d-4a85-71d5-bbee-c79b20705780" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable_019e3e2d-4a85-71d5-bbee-c79b20705780" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationNumberOfCommonStockSharesAcquiredReceivedCash_019e22d7-dcd1-7699-ad8d-0cd7c2598ba6" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationNumberOfCommonStockSharesAcquiredReceivedCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:to="loc_sbcf_BusinessCombinationNumberOfCommonStockSharesAcquiredReceivedCash_019e22d7-dcd1-7699-ad8d-0cd7c2598ba6" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableCashPaidPerAcquireeShare_019e22d7-dcd1-7549-b983-ac165d499e4a" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableCashPaidPerAcquireeShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:to="loc_sbcf_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableCashPaidPerAcquireeShare_019e22d7-dcd1-7549-b983-ac165d499e4a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross_019e22d7-dcd1-7faf-84e1-c7bd9e51d135" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireBusinessesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesGross_019e22d7-dcd1-7faf-84e1-c7bd9e51d135" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_PaymentsToAcquireBusinessesOptionHolders_019e22d7-dcd1-7281-82e7-9e109ac009bf" xlink:href="sbcf-20260630.xsd#sbcf_PaymentsToAcquireBusinessesOptionHolders"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:to="loc_sbcf_PaymentsToAcquireBusinessesOptionHolders_019e22d7-dcd1-7281-82e7-9e109ac009bf" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_019e22d7-dcd1-7722-bf8e-8340c89693e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_019e22d7-dcd1-7722-bf8e-8340c89693e8" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationPreferredStockToCommonStockRatio_019e22d7-dcd1-7c45-ba4d-bdc0a97eac89" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationPreferredStockToCommonStockRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ebb-873f-a69b38bea67c" xlink:to="loc_sbcf_BusinessCombinationPreferredStockToCommonStockRatio_019e22d7-dcd1-7c45-ba4d-bdc0a97eac89" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/BusinessCombinationsScheduleofFairValueofAssetsAcquiredandLiabilitiesAssumedDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#BusinessCombinationsScheduleofFairValueofAssetsAcquiredandLiabilitiesAssumedDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/BusinessCombinationsScheduleofFairValueofAssetsAcquiredandLiabilitiesAssumedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7f2b-b169-d833457cb618" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7277-bd9e-aae41a1fbd88" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7f2b-b169-d833457cb618" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7277-bd9e-aae41a1fbd88" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-77a4-bbfa-dc64c221a4b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7277-bd9e-aae41a1fbd88" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-77a4-bbfa-dc64c221a4b7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-77a4-bbfa-dc64c221a4b7_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-77a4-bbfa-dc64c221a4b7" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-77a4-bbfa-dc64c221a4b7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7648-b812-a2d9fcad5ca7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-77a4-bbfa-dc64c221a4b7" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7648-b812-a2d9fcad5ca7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_VillagesBancorporationIncMember_019e3e30-9d58-7265-afb1-c2ccc2dfd126" xlink:href="sbcf-20260630.xsd#sbcf_VillagesBancorporationIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7648-b812-a2d9fcad5ca7" xlink:to="loc_sbcf_VillagesBancorporationIncMember_019e3e30-9d58-7265-afb1-c2ccc2dfd126" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_HeartlandBancsharesIncMember_019e22d7-dcd1-76d7-a705-d0068a14a2ff" xlink:href="sbcf-20260630.xsd#sbcf_HeartlandBancsharesIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7648-b812-a2d9fcad5ca7" xlink:to="loc_sbcf_HeartlandBancsharesIncMember_019e22d7-dcd1-76d7-a705-d0068a14a2ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementAxis_019eb1dd-5e81-742c-b735-3924586a36da" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RestatementAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7277-bd9e-aae41a1fbd88" xlink:to="loc_srt_RestatementAxis_019eb1dd-5e81-742c-b735-3924586a36da" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementDomain_019eb1dd-5e81-742c-b735-3924586a36da_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RestatementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RestatementAxis_019eb1dd-5e81-742c-b735-3924586a36da" xlink:to="loc_srt_RestatementDomain_019eb1dd-5e81-742c-b735-3924586a36da_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RestatementDomain_019eb1dd-5e81-776a-bcc6-e2c4b1047474" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RestatementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RestatementAxis_019eb1dd-5e81-742c-b735-3924586a36da" xlink:to="loc_srt_RestatementDomain_019eb1dd-5e81-776a-bcc6-e2c4b1047474" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioPreviouslyReportedMember_019eb1dd-5e81-7d37-94ca-5364dd571376" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScenarioPreviouslyReportedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RestatementDomain_019eb1dd-5e81-776a-bcc6-e2c4b1047474" xlink:to="loc_srt_ScenarioPreviouslyReportedMember_019eb1dd-5e81-7d37-94ca-5364dd571376" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7f2b-b169-d833457cb618" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_019e22d7-dcd1-709a-8e58-7c1e92e2e20f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_019e22d7-dcd1-709a-8e58-7c1e92e2e20f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationRecognizedAssetAcquiredInvestmentSecurities_019e22d7-dcd1-7426-b710-54ed50116b1b" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationRecognizedAssetAcquiredInvestmentSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:to="loc_sbcf_BusinessCombinationRecognizedAssetAcquiredInvestmentSecurities_019e22d7-dcd1-7426-b710-54ed50116b1b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationRecognizedAssetAcquiredFinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-78ac-abe6-436fbac09f09" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationRecognizedAssetAcquiredFinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:to="loc_sbcf_BusinessCombinationRecognizedAssetAcquiredFinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_019e22d7-dcd1-78ac-abe6-436fbac09f09" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentFinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_019eb1dd-d67a-7bbe-a5c2-6edd9c417f33" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentFinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:to="loc_sbcf_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentFinancingReceivableExcludingAccruedInterestAfterAllowanceForCreditLoss_019eb1dd-d67a-7bbe-a5c2-6edd9c417f33" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_019e22d7-dcd1-79c2-b0de-0620b14e3223" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_019e22d7-dcd1-79c2-b0de-0620b14e3223" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_019e22d7-dcd1-7b42-9639-7ec86583139f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_019e22d7-dcd1-7b42-9639-7ec86583139f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_019e22d7-dcd1-74e1-8267-5b95a6e9df9e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:to="loc_us-gaap_Goodwill_019e22d7-dcd1-74e1-8267-5b95a6e9df9e" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillPurchaseAccountingAdjustments_019eb1dd-d67a-7c08-8606-bbc7b726872d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GoodwillPurchaseAccountingAdjustments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:to="loc_us-gaap_GoodwillPurchaseAccountingAdjustments_019eb1dd-d67a-7c08-8606-bbc7b726872d" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_019e22d7-dcd1-7a45-8d07-448d473f3eb7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_019e22d7-dcd1-7a45-8d07-448d473f3eb7" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019e22d7-dcd1-7db9-b43b-6462909290e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_019e22d7-dcd1-7db9-b43b-6462909290e8" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentAssets_019eb1dd-d67a-74f8-a54b-79f95dd4a025" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract_019e22d7-dcd1-768b-b253-48f1c4b949e9" xlink:to="loc_sbcf_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentAssets_019eb1dd-d67a-74f8-a54b-79f95dd4a025" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019e22d7-dcd1-7d9b-acfb-4a002f3f5dbd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7f2b-b169-d833457cb618" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019e22d7-dcd1-7d9b-acfb-4a002f3f5dbd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationRecognizedLiabilityAssumedDeposits_019e22d7-dcd1-7870-a56e-ded0f97110e0" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationRecognizedLiabilityAssumedDeposits"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019e22d7-dcd1-7d9b-acfb-4a002f3f5dbd" xlink:to="loc_sbcf_BusinessCombinationRecognizedLiabilityAssumedDeposits_019e22d7-dcd1-7870-a56e-ded0f97110e0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationRecognizedLiabilityAssumedSecuritiesSoldUnderAgreementsToRepurchase_019e3e1f-3988-71f5-b716-29e7677fe07c" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationRecognizedLiabilityAssumedSecuritiesSoldUnderAgreementsToRepurchase"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019e22d7-dcd1-7d9b-acfb-4a002f3f5dbd" xlink:to="loc_sbcf_BusinessCombinationRecognizedLiabilityAssumedSecuritiesSoldUnderAgreementsToRepurchase_019e3e1f-3988-71f5-b716-29e7677fe07c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_019e22d7-dcd1-7431-ba7b-0978d5ca08dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019e22d7-dcd1-7d9b-acfb-4a002f3f5dbd" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_019e22d7-dcd1-7431-ba7b-0978d5ca08dc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentNoncurrentLiabilitiesOther_019eb1dd-d67a-76bf-acc5-3cca28972dff" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentNoncurrentLiabilitiesOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019e22d7-dcd1-7d9b-acfb-4a002f3f5dbd" xlink:to="loc_sbcf_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentNoncurrentLiabilitiesOther_019eb1dd-d67a-76bf-acc5-3cca28972dff" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019e22d7-dcd1-7890-a190-30fb5fac29bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019e22d7-dcd1-7d9b-acfb-4a002f3f5dbd" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_019e22d7-dcd1-7890-a190-30fb5fac29bc" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentLiabilities_019eb1dd-d67a-737c-8bb0-1f07f5059ecf" xlink:href="sbcf-20260630.xsd#sbcf_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract_019e22d7-dcd1-7d9b-acfb-4a002f3f5dbd" xlink:to="loc_sbcf_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentLiabilities_019eb1dd-d67a-737c-8bb0-1f07f5059ecf" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/BusinessCombinationsScheduleofFairValueofAcquiredLoansDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#BusinessCombinationsScheduleofFairValueofAcquiredLoansDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/BusinessCombinationsScheduleofFairValueofAcquiredLoansDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ca8-a4d7-878f64f9494a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7f4b-a922-ac28bee8dcc6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ca8-a4d7-878f64f9494a" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7f4b-a922-ac28bee8dcc6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-7d4b-ba9c-c3a66917efb3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7f4b-a922-ac28bee8dcc6" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-7d4b-ba9c-c3a66917efb3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7d4b-ba9c-c3a66917efb3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-7d4b-ba9c-c3a66917efb3" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7d4b-ba9c-c3a66917efb3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7340-8c72-b1296eb1b9b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-7d4b-ba9c-c3a66917efb3" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7340-8c72-b1296eb1b9b7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_VillagesBancorporationIncMember_019e3e37-3cf0-70b8-96d0-9a6307e077c1" xlink:href="sbcf-20260630.xsd#sbcf_VillagesBancorporationIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7340-8c72-b1296eb1b9b7" xlink:to="loc_sbcf_VillagesBancorporationIncMember_019e3e37-3cf0-70b8-96d0-9a6307e077c1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_HeartlandBancsharesIncMember_019e22d7-dcd1-7722-b842-43eb962c0684" xlink:href="sbcf-20260630.xsd#sbcf_HeartlandBancsharesIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7340-8c72-b1296eb1b9b7" xlink:to="loc_sbcf_HeartlandBancsharesIncMember_019e22d7-dcd1-7722-b842-43eb962c0684" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-744a-9765-19f0b62855f0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7f4b-a922-ac28bee8dcc6" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-744a-9765-19f0b62855f0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-744a-9765-19f0b62855f0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-744a-9765-19f0b62855f0" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-744a-9765-19f0b62855f0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7b21-bd8c-635954da891a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e22d7-dcd1-744a-9765-19f0b62855f0" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7b21-bd8c-635954da891a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-766d-9e06-a2007f49f725" xlink:href="sbcf-20260630.xsd#sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7b21-bd8c-635954da891a" xlink:to="loc_sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember_019e22d7-dcd1-766d-9e06-a2007f49f725" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-75a1-b239-a120f3147669" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7b21-bd8c-635954da891a" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentOwnerOccupiedMember_019e22d7-dcd1-75a1-b239-a120f3147669" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-7a37-be05-5b7fb7ca6cbd" xlink:href="sbcf-20260630.xsd#sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7b21-bd8c-635954da891a" xlink:to="loc_sbcf_CommercialRealEstatePortfolioSegmentNonOwnerOccupiedMember_019e22d7-dcd1-7a37-be05-5b7fb7ca6cbd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-758f-a2d9-40c6d3c339f1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResidentialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7b21-bd8c-635954da891a" xlink:to="loc_us-gaap_ResidentialPortfolioSegmentMember_019e22d7-dcd1-758f-a2d9-40c6d3c339f1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-7048-bc08-d113ab348836" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7b21-bd8c-635954da891a" xlink:to="loc_us-gaap_CommercialPortfolioSegmentMember_019e22d7-dcd1-7048-bc08-d113ab348836" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-7021-a28c-5528a199d11f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsumerPortfolioSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e22d7-dcd1-7b21-bd8c-635954da891a" xlink:to="loc_us-gaap_ConsumerPortfolioSegmentMember_019e22d7-dcd1-7021-a28c-5528a199d11f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationAcquiredReceivablesGrossContractualAmount_019e22d7-dcd1-72f7-a7b7-76aac4835468" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationAcquiredReceivablesGrossContractualAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ca8-a4d7-878f64f9494a" xlink:to="loc_us-gaap_BusinessCombinationAcquiredReceivablesGrossContractualAmount_019e22d7-dcd1-72f7-a7b7-76aac4835468" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationAcquiredReceivablesFairValue_019e22d7-dcd1-7d50-9a86-ab455f22b940" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationAcquiredReceivablesFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ca8-a4d7-878f64f9494a" xlink:to="loc_us-gaap_BusinessCombinationAcquiredReceivablesFairValue_019e22d7-dcd1-7d50-9a86-ab455f22b940" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/BusinessCombinationsScheduleofLoanswithDeteriorationofCreditQualityDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#BusinessCombinationsScheduleofLoanswithDeteriorationofCreditQualityDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/BusinessCombinationsScheduleofLoanswithDeteriorationofCreditQualityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ea3-9f52-1457ac511f7a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7538-a480-197ef65a020d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ea3-9f52-1457ac511f7a" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7538-a480-197ef65a020d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-718f-97e7-4f455c0a3f77" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-7538-a480-197ef65a020d" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-718f-97e7-4f455c0a3f77" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-718f-97e7-4f455c0a3f77_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-718f-97e7-4f455c0a3f77" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-718f-97e7-4f455c0a3f77_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7461-9c24-524c5ff8568f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-718f-97e7-4f455c0a3f77" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7461-9c24-524c5ff8568f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_VillagesBancorporationIncMember_019e22d7-dcd1-7e06-a55e-f1e4b680f934" xlink:href="sbcf-20260630.xsd#sbcf_VillagesBancorporationIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7461-9c24-524c5ff8568f" xlink:to="loc_sbcf_VillagesBancorporationIncMember_019e22d7-dcd1-7e06-a55e-f1e4b680f934" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtParValue_019e22d7-dcd1-76e9-b36d-f583f5eb49e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtParValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ea3-9f52-1457ac511f7a" xlink:to="loc_us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtParValue_019e22d7-dcd1-76e9-b36d-f583f5eb49e8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAllowanceForCreditLossAtAcquisitionDate_019e22d7-dcd1-77e4-8e4f-2275bdad45f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAllowanceForCreditLossAtAcquisitionDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ea3-9f52-1457ac511f7a" xlink:to="loc_us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAllowanceForCreditLossAtAcquisitionDate_019e22d7-dcd1-77e4-8e4f-2275bdad45f2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationDiscountPremium_019e22d7-dcd1-7cd6-b163-8f3988d4cd17" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationDiscountPremium"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ea3-9f52-1457ac511f7a" xlink:to="loc_us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationDiscountPremium_019e22d7-dcd1-7cd6-b163-8f3988d4cd17" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtPurchasePrice_019e22d7-dcd1-7596-8fe3-079be852adfb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtPurchasePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-7ea3-9f52-1457ac511f7a" xlink:to="loc_us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtPurchasePrice_019e22d7-dcd1-7596-8fe3-079be852adfb" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.seacoastbanking.com/role/BusinessCombinationsScheduleofProFormaInformationDetails" xlink:type="simple" xlink:href="sbcf-20260630.xsd#BusinessCombinationsScheduleofProFormaInformationDetails"/>
  <link:definitionLink xlink:role="http://www.seacoastbanking.com/role/BusinessCombinationsScheduleofProFormaInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-70a2-b75c-b16e968a8b6d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-75a7-b2d6-eab13838ad30" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-70a2-b75c-b16e968a8b6d" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-75a7-b2d6-eab13838ad30" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-7b4c-b283-0bbbf0510df6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_019e22d7-dcd1-75a7-b2d6-eab13838ad30" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-7b4c-b283-0bbbf0510df6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7b4c-b283-0bbbf0510df6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-7b4c-b283-0bbbf0510df6" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7b4c-b283-0bbbf0510df6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7bfd-af80-dc205593f414" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e22d7-dcd1-7b4c-b283-0bbbf0510df6" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7bfd-af80-dc205593f414" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_sbcf_VillagesBancorporationIncMember_019e22d7-dcd1-7d0b-aaf9-7fc497b6592d" xlink:href="sbcf-20260630.xsd#sbcf_VillagesBancorporationIncMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e22d7-dcd1-7bfd-af80-dc205593f414" xlink:to="loc_sbcf_VillagesBancorporationIncMember_019e22d7-dcd1-7d0b-aaf9-7fc497b6592d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionsProFormaRevenue_019e22d7-dcd1-7884-839e-9677c71aa92e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionsProFormaRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-70a2-b75c-b16e968a8b6d" xlink:to="loc_us-gaap_BusinessAcquisitionsProFormaRevenue_019e22d7-dcd1-7884-839e-9677c71aa92e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss_019e22d7-dcd1-7c6a-847e-17c793d9c775" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-70a2-b75c-b16e968a8b6d" xlink:to="loc_us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss_019e22d7-dcd1-7c6a-847e-17c793d9c775" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted_019e22d7-dcd1-710c-89b6-ccac695cffa5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-70a2-b75c-b16e968a8b6d" xlink:to="loc_us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted_019e22d7-dcd1-710c-89b6-ccac695cffa5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic_019e22d7-dcd1-7e71-abe3-68dab2cc1795" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_019e22d7-dcd1-70a2-b75c-b16e968a8b6d" xlink:to="loc_us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic_019e22d7-dcd1-7e71-abe3-68dab2cc1795" xlink:type="arc" order="3"/>
  </link:definitionLink>
</link:linkbase>
