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        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2025-03-31</maturityDt>
          <couponKind>Fixed</couponKind>
          <annualizedRt>3.88000000</annualizedRt>
          <isDefault>N</isDefault>
          <areIntrstPmntsInArrs>N</areIntrstPmntsInArrs>
          <isPaidKind>N</isPaidKind>
        </debtSec>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>MFS Value Fund</name>
        <lei>HV6C0RMURVKFUQ3UTB42</lei>
        <title>MFS Value Fund</title>
        <cusip>55273H353</cusip>
        <identifiers>
          <isin value="US55273H3536"/>
        </identifiers>
        <balance>179900.01000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>10022229.56000000</valUSD>
        <pctVal>30.25768121232</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Options Clearing Corp.</name>
        <lei>549300CII6SLYGKNHA04</lei>
        <title>S+P 500 INDEX</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Bloomberg Identifier" value="BBG01NBX5S97"/>
        </identifiers>
        <balance>4.00000000</balance>
        <units>NC</units>
        <curCd>USD</curCd>
        <valUSD>17880.00000000</valUSD>
        <pctVal>0.053980737203</pctVal>
        <payoffProfile>N/A</payoffProfile>
        <assetCat>DE</assetCat>
        <issuerConditional desc="derivative" issuerCat="OTHER"/>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</fairValLevel>
        <derivativeInfo>
          <optionSwaptionWarrantDeriv derivCat="OPT">
            <counterparties>
              <counterpartyName>Options Clearing Corp.</counterpartyName>
              <counterpartyLei>549300CII6SLYGKNHA04</counterpartyLei>
            </counterparties>
            <putOrCall>Put</putOrCall>
            <writtenOrPur>Purchased</writtenOrPur>
            <descRefInstrmnt>
              <indexBasketInfo>
                <indexName>S&amp;P 500 Index</indexName>
                <indexIdentifier>SPX INDEX</indexIdentifier>
              </indexBasketInfo>
            </descRefInstrmnt>
            <shareNo>100.00000000</shareNo>
            <exercisePrice>4600.00000000</exercisePrice>
            <exercisePriceCurCd>USD</exercisePriceCurCd>
            <expDt>2025-09-19</expDt>
            <delta>XXXX</delta>
            <unrealizedAppr>-16092.00000000</unrealizedAppr>
          </optionSwaptionWarrantDeriv>
        </derivativeInfo>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Options Clearing Corp.</name>
        <lei>549300CII6SLYGKNHA04</lei>
        <title>S+P 500 INDEX</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Bloomberg Identifier" value="BBG0139BM735"/>
        </identifiers>
        <balance>4.00000000</balance>
        <units>NC</units>
        <curCd>USD</curCd>
        <valUSD>240.00000000</valUSD>
        <pctVal>0.000724573653</pctVal>
        <payoffProfile>N/A</payoffProfile>
        <assetCat>DE</assetCat>
        <issuerConditional desc="derivative" issuerCat="OTHER"/>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <derivativeInfo>
          <optionSwaptionWarrantDeriv derivCat="OPT">
            <counterparties>
              <counterpartyName>Options Clearing Corp.</counterpartyName>
              <counterpartyLei>549300CII6SLYGKNHA04</counterpartyLei>
            </counterparties>
            <putOrCall>Put</putOrCall>
            <writtenOrPur>Purchased</writtenOrPur>
            <descRefInstrmnt>
              <indexBasketInfo>
                <indexName>S&amp;P 500 Index</indexName>
                <indexIdentifier>SPX Index</indexIdentifier>
              </indexBasketInfo>
            </descRefInstrmnt>
            <shareNo>100.00000000</shareNo>
            <exercisePrice>4200.00000000</exercisePrice>
            <exercisePriceCurCd>USD</exercisePriceCurCd>
            <expDt>2024-12-20</expDt>
            <delta>XXXX</delta>
            <unrealizedAppr>-71972.00000000</unrealizedAppr>
          </optionSwaptionWarrantDeriv>
        </derivativeInfo>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
    </invstOrSecs>
    <explntrNotes>
      <explntrNote note="Monthly returns presented in Item B.5(a) have been calculated without deducting any applicable sales loads or redemption fees." noteItem="B.5.a"/>
    </explntrNotes>
    <signature>
      <ncom:dateSigned>2024-12-13</ncom:dateSigned>
      <ncom:nameOfApplicant>MFS SERIES TRUST X</ncom:nameOfApplicant>
      <ncom:signature>James Byrne</ncom:signature>
      <ncom:signerName>James Byrne</ncom:signerName>
      <ncom:title>Assistant Treasurer</ncom:title>
    </signature>
  </formData>
</edgarSubmission>
