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          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>MFS Commodity Strategy Fund</name>
        <lei>T0OEQ8I3F6DXUJCOV412</lei>
        <title>MFS Commodity Strategy Fund</title>
        <cusip>55276T826</cusip>
        <identifiers>
          <isin value="US55276T8264"/>
        </identifiers>
        <balance>380606.10000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>1408242.57000000</valUSD>
        <pctVal>5.008863806138</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>MFS Blended Research Emerging Markets Equity Fund</name>
        <lei>549300N4Y1QEM5QDU861</lei>
        <title>MFS Blended Research Emerging Markets Equity Fund</title>
        <cusip>552987240</cusip>
        <identifiers>
          <isin value="US5529872401"/>
        </identifiers>
        <balance>20044.83000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>281228.98000000</valUSD>
        <pctVal>1.000280554762</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>MFS Blended Research International Equity Fund</name>
        <lei>254900SJDP6D81SAVM86</lei>
        <title>MFS Blended Research International Equity Fund</title>
        <cusip>552987448</cusip>
        <identifiers>
          <isin value="US5529874480"/>
        </identifiers>
        <balance>230163.05000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>3100296.27000000</valUSD>
        <pctVal>11.02719240699</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>MFS Mid Cap Value Fund</name>
        <lei>BXHSCSBXYY1DOHP6E209</lei>
        <title>MFS Mid Cap Value Fund</title>
        <cusip>55273W475</cusip>
        <identifiers>
          <isin value="US55273W4758"/>
        </identifiers>
        <balance>42673.23000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>1401388.97000000</valUSD>
        <pctVal>4.984486792041</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>MFS International Growth Fund</name>
        <lei>PTNAY8DC4VJYOKVJ5B83</lei>
        <title>MFS International Growth Fund</title>
        <cusip>552746356</cusip>
        <identifiers>
          <isin value="US5527463567"/>
        </identifiers>
        <balance>22748.02000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>988401.25000000</valUSD>
        <pctVal>3.515564258980</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>
    </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>2025-03-03</ncom:dateSigned>
      <ncom:nameOfApplicant>MFS SERIES TRUST XII</ncom:nameOfApplicant>
      <ncom:signature>James Byrne</ncom:signature>
      <ncom:signerName>James Byrne</ncom:signerName>
      <ncom:title>Assistant Treasurer</ncom:title>
    </signature>
  </formData>
  <documents>XXXX</documents>
</edgarSubmission>
