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        <filerCredentials>
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          <ccc>XXXXXXXX</ccc>
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      <liveTestFlag>LIVE</liveTestFlag>


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    <issuerInfo>
      <issuerCik>0001158324</issuerCik>
      <issuerName>COGENT COMMUNICATIONS HOLDINGS, INC.</issuerName>
      <secFileNumber>000-51829</secFileNumber>
      <issuerAddress>
        <com:street1>2450 N STREET, NW</com:street1>
        <com:city>WASHINGTON</com:city>
        <com:stateOrCountry>DC</com:stateOrCountry>
        <com:zipCode>20037</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>2022954200</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>BUBECK JAMES</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>COMMON</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>THE CHARLES SCHWAB CORPORATION</name>
        <address>
          <com:street1>3000 Schwab Way</com:street1>
          <com:city>Westlake</com:city>
          <com:stateOrCountry>TX</com:stateOrCountry>
          <com:zipCode>76262</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>1920</noOfUnitsSold>
      <aggregateMarketValue>147108.00</aggregateMarketValue>
      <noOfUnitsOutstanding>47425367</noOfUnitsOutstanding>
      <approxSaleDate>03/01/2024</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>COMMON</securitiesClassTitle>
      <acquiredDate>03/01/2024</acquiredDate>
      <natureOfAcquisitionTransaction>STOCK GRANT</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>ISSUER</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>1920</amountOfSecuritiesAcquired>
      <paymentDate>03/01/2024</paymentDate>
      <natureOfPayment>NA</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>JAMES BUBECK</name>
        <address>
          <com:street1>2450 N Street N.W.</com:street1>
          <com:city>Washington</com:city>
          <com:stateOrCountry>DC</com:stateOrCountry>
          <com:zipCode>20037</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>COMMON</securitiesClassTitle>
      <saleDate>12/05/2023</saleDate>
      <amountOfSecuritiesSold>1920</amountOfSecuritiesSold>
      <grossProceeds>126957.00</grossProceeds>
    </securitiesSoldInPast3Months>
    <remarks>FULL ACCOUNT TITLE: Theresa &amp; James as trustees for Theresa &amp; James Bubeck Family Trust</remarks>
    <noticeSignature>
      <noticeDate>03/01/2024</noticeDate>
      <planAdoptionDates>
        <planAdoptionDate>12/09/2022</planAdoptionDate>
      </planAdoptionDates>
      <signature>JAMES R. BUBECK</signature>
    </noticeSignature>
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144
0001654298
XXXXXXXX
LIVE
0001158324
COGENT COMMUNICATIONS HOLDINGS, INC.
000-51829
2450 N STREET, NW
WASHINGTON
DC
20037
2022954200
BUBECK JAMES
Officer
COMMON
THE CHARLES SCHWAB CORPORATION
3000 Schwab Way
Westlake
TX
76262
1920
147108.00
47425367
03/01/2024
NASDAQ
COMMON
03/01/2024
STOCK GRANT
ISSUER
N
1920
03/01/2024
NA
N
JAMES BUBECK
2450 N Street N.W.
Washington
DC
20037
COMMON
12/05/2023
1920
126957.00
FULL ACCOUNT TITLE: Theresa & James as trustees for Theresa & James Bubeck Family Trust
03/01/2024
12/09/2022
JAMES R. BUBECK