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      <subAdviser>
        <adviserName>FIDELITY MANAGEMENT &amp; RESEARCH (HONG KONG) LIMITED</adviserName>
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      <subAdviser>
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    <signature>
      <registrant>Fidelity Colchester Street Trust: Treasury Only Portfolio</registrant>
      <signatureDate>2023-06-02</signatureDate>
      <signature>Laura M. Del Prato</signature>
      <nameOfSigningOfficer>Laura M. Del Prato</nameOfSigningOfficer>
      <titleOfSigningOfficer>President and Treasurer</titleOfSigningOfficer>
    </signature>
  </formData>
</edgarSubmission>
