<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2004-11-26</periodOfReport>

    <dateOfOriginalSubmission>2004-11-26</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000730708</issuerCik>
        <issuerName>SEACOAST BANKING CORP OF FLORIDA</issuerName>
        <issuerTradingSymbol>SBCF</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001078596</rptOwnerCik>
            <rptOwnerName>HUDSON DENNIS S III</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>815 COLORADO AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>P O BOX 9012</rptOwnerStreet2>
            <rptOwnerCity>STUART</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>34995-9012</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President &amp; CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-11-26</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>926</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>23.17</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>55041</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>56100</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1121778</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Shares held by Sherwood Partners, Ltd.</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>24200</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Shares held by spouse</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Common Stock Right to Buy</value>
                <footnoteId id="F3"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>5.303</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>1999-02-21</value>
            </exerciseDate>
            <expirationDate>
                <value>2005-02-20</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>19800</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>19800</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Common Stock Right to Buy</value>
                <footnoteId id="F4"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>6.5909</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2000-06-18</value>
            </exerciseDate>
            <expirationDate>
                <value>2006-06-17</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>19800</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>19800</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Common Stock Right to Buy</value>
                <footnoteId id="F4"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>7.7273</value>
                <footnoteId id="F5"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2001-05-20</value>
            </exerciseDate>
            <expirationDate>
                <value>2007-05-20</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>19800</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>19800</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Common Stock Right to Buy</value>
                <footnoteId id="F4"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>8.7879</value>
                <footnoteId id="F6"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>1999-07-01</value>
            </exerciseDate>
            <expirationDate>
                <value>2008-06-30</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>72600</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>72600</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Common Stock Right to Buy</value>
                <footnoteId id="F7"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>17.08</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F8"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-11-17</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>75000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>75000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">14,000 shares represent unvested shares in a time-based restricted stock award granted under Seacoast's 2000 Long-Term Incentive Plan which shall vest in 3,500 share increments on each anniversary of the date of grant (11/17/03), subject to continued employment. Another 17,500 shares represent a performance based restricted stock award granted under the 2000 Incentive Plan which shall vest, subject to continued employment, over a 5-year performance period beginning 1/1/2004, as to the following percentage of shares based on the Company's EPS growth over the performance period compared to fiscal year 2003 EPS: 38% EPS growth=25% vesting; 50% EPS growth=50% vesting; 75% EPS growth=75% vesting; 85% EPS growth=100% vesting. Notwithstanding the above, 100% of the performance based award shall vest on the 5th anniversary of the grant date if the Company achieves an ROE of at least 16.5% for 3 consecutive quarters during the performance period, regardless of whether the EPS targets are met.</footnote>
        <footnote id="F2">Shares held jointly with spouse</footnote>
        <footnote id="F3">Granted pursuant to Seacoast Banking Corporation of Florida's 1991 Stock Option and Stock Appreciation Rights Plan</footnote>
        <footnote id="F4">Granted pursuant to Seacoast Banking Corporation of Florida's 1996 Long-Term Incentive Plan</footnote>
        <footnote id="F5">The Form 4 filing software only allows for numbers to be expressed up to four decimal places.  The actual price of Mr. Hudson's stock options is $7.72727.</footnote>
        <footnote id="F6">The Form 4 filing software only allows for numbers to be expressed up to four decimal places.  The actual price of Mr. Hudson's stock options is $8.787879.</footnote>
        <footnote id="F7">Granted pursuant to Seacoast Banking Corporation of Florida's 2000 Long-Term Incentive Plan.</footnote>
        <footnote id="F8">Vests over 5 years at the rate of 20% on the first anniversary of the date of grant (11/17/03) and then at the rate of 20% on each of the following four anniversaries thereafter, subject to continued employment.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Sharon Mehl as Power of Attorney for Dennis S. Hudson, III</signatureName>
        <signatureDate>2004-12-16</signatureDate>
    </ownerSignature>
</ownershipDocument>

