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        <fairValLevel>1</fairValLevel>
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        <fairValLevel>2</fairValLevel>
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    <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>2023-09-28</ncom:dateSigned>
      <ncom:nameOfApplicant>MFS SERIES TRUST X</ncom:nameOfApplicant>
      <ncom:signature>Kasey Phillips</ncom:signature>
      <ncom:signerName>Kasey Phillips</ncom:signerName>
      <ncom:title>Assistant Treasurer</ncom:title>
    </signature>
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  <documents>XXXX</documents>
</edgarSubmission>
