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        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <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>229259.72000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>11162655.62000000</valUSD>
        <pctVal>2.019485995243</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 Inflation Adjusted Bond Fund</name>
        <lei>VOHO802M9IKG3IZTEN75</lei>
        <title>MFS Inflation Adjusted Bond Fund</title>
        <cusip>55274K884</cusip>
        <identifiers>
          <isin value="US55274K8844"/>
        </identifiers>
        <balance>5987534.60000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>55264944.33000000</valUSD>
        <pctVal>9.998228459396</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 Commodity Strategy Fund</name>
        <lei>T0OEQ8I3F6DXUJCOV412</lei>
        <title>MFS Commodity Strategy Fund</title>
        <cusip>55276T826</cusip>
        <identifiers>
          <isin value="US55276T8264"/>
        </identifiers>
        <balance>2954848.43000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>10844293.73000000</valUSD>
        <pctVal>1.961889720650</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>990932.12000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>14130692.09000000</valUSD>
        <pctVal>2.556446758755</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 Ltd Maturity Fund</name>
        <lei>7ER38PJ2TK60L3Y32478</lei>
        <title>MFS Ltd Maturity Fund</title>
        <cusip>55274K801</cusip>
        <identifiers>
          <isin value="US55274K8018"/>
        </identifiers>
        <balance>18694768.53000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>109925238.95000000</valUSD>
        <pctVal>19.88706703318</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>278993.84000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>8300066.62000000</valUSD>
        <pctVal>1.501602205539</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 Emerging Markets Debt Local Currency Fund</name>
        <lei>5493001KPK8UJ27DMD68</lei>
        <title>MFS Emerging Markets Debt Local Currency Fund</title>
        <cusip>552746323</cusip>
        <identifiers>
          <isin value="US5527463237"/>
        </identifiers>
        <balance>997822.02000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5547890.45000000</valUSD>
        <pctVal>1.003693695149</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>62990.13000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2822587.86000000</valUSD>
        <pctVal>0.510647004409</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>2025-05-15</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>
</edgarSubmission>
