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      <regStreet1>111 HUNTINGTON AVENUE</regStreet1>
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          <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>147398.08000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>543898.90000000</valUSD>
        <pctVal>4.956901517875</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>8391.14000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>109420.40000000</valUSD>
        <pctVal>0.997218686867</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>5493006W0U1M8BQLTQ30</lei>
        <title>MFS Blended Research International Equity Fund</title>
        <cusip>552987448</cusip>
        <identifiers>
          <isin value="US5529874480"/>
        </identifiers>
        <balance>97724.83000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>1198106.40000000</valUSD>
        <pctVal>10.91911646215</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>17696.50000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>544698.33000000</valUSD>
        <pctVal>4.964187239137</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>9166.18000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>380579.88000000</valUSD>
        <pctVal>3.468469939624</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>2023-08-21</ncom:dateSigned>
      <ncom:nameOfApplicant>MFS SERIES TRUST XII</ncom:nameOfApplicant>
      <ncom:signature>Kasey Phillips</ncom:signature>
      <ncom:signerName>Kasey Phillips</ncom:signerName>
      <ncom:title>Assistant Treasurer</ncom:title>
    </signature>
  </formData>
  <documents>XXXX</documents>
</edgarSubmission>
