<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/ownership" xmlns:com="http://www.sec.gov/edgar/common">
  <headerData>
    <submissionType>144</submissionType>
    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0001654298</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>



    </filerInfo>
  </headerData>
  <formData>
    <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>Charles Schwab Corp.</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>486238.00</aggregateMarketValue>
      <noOfUnitsOutstanding>48623846</noOfUnitsOutstanding>
      <approxSaleDate>12/05/2023</approxSaleDate>
      <securitiesExchangeName>Nasdaq</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>12/01/2023</acquiredDate>
      <natureOfAcquisitionTransaction>Performance Based Stock Grants</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>2400</amountOfSecuritiesAcquired>
      <paymentDate>12/01/2023</paymentDate>
      <natureOfPayment>N/A</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>12/01/2023</saleDate>
      <amountOfSecuritiesSold>1920</amountOfSecuritiesSold>
      <grossProceeds>122296.90</grossProceeds>
    </securitiesSoldInPast3Months>
    <remarks>Client did not pay for the shares they were stock grants

Sold out of account: T BUBECK &amp; J BUBECK TTEE THERESA &amp; JAMES BUBECK FAMILY
U/A DTD 05/06/2021</remarks>
    <noticeSignature>
      <noticeDate>12/05/2023</noticeDate>
      <signature>James Bubeck</signature>
    </noticeSignature>
  </formData>
</edgarSubmission>
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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
Charles Schwab Corp.
3000 Schwab Way
Westlake
TX
76262
1920
486238.00
48623846
12/05/2023
Nasdaq
Common
12/01/2023
Performance Based Stock Grants
Issuer
N
2400
12/01/2023
N/A
N
James Bubeck
2450 N Street N.W.
Washington
DC
20037
Common
12/01/2023
1920
122296.90
Client did not pay for the shares they were stock grants

Sold out of account: T BUBECK & J BUBECK TTEE THERESA & JAMES BUBECK FAMILY
U/A DTD 05/06/2021
12/05/2023
James Bubeck