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            <ns2:filer>
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                    <ns2:cik>0001378530</ns2:cik>
                    <ns2:ccc>XXXXXXXX</ns2:ccc>
                </ns2:filerCredentials>
            </ns2:filer>
            <ns2:liveTestFlag>LIVE</ns2:liveTestFlag>



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    </ns2:headerData>
    <ns2:formData>
        <ns2:issuerInfo>
            <ns2:issuerCik>0001158324</ns2:issuerCik>
            <ns2:issuerName>Cogent Communications Holdings, Inc.</ns2:issuerName>
            <ns2:secFileNumber>000-51829</ns2:secFileNumber>
            <ns2:issuerAddress>
                <com:street1>1015 31st Street</com:street1>
                <com:city>Washington</com:city>
                <com:stateOrCountry>DC</com:stateOrCountry>
                <com:zipCode>20007</com:zipCode>
            </ns2:issuerAddress>
            <ns2:issuerContactPhone>1-202-295-4200</ns2:issuerContactPhone>
            <ns2:nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>David Blake Bath</ns2:nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
            <ns2:relationshipsToIssuer>
                <ns2:relationshipToIssuer>Director</ns2:relationshipToIssuer>
            </ns2:relationshipsToIssuer>
        </ns2:issuerInfo>
        <ns2:securitiesInformation>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:brokerOrMarketmakerDetails>
                <ns2:name>Goldman Sachs &amp; Co. LLC</ns2:name>
                <ns2:address>
                    <com:street1>200 West Street</com:street1>
                    <com:city>New York</com:city>
                    <com:stateOrCountry>NY</com:stateOrCountry>
                    <com:zipCode>10282</com:zipCode>
                </ns2:address>
            </ns2:brokerOrMarketmakerDetails>
            <ns2:noOfUnitsSold>18000</ns2:noOfUnitsSold>
            <ns2:aggregateMarketValue>1197000</ns2:aggregateMarketValue>
            <ns2:noOfUnitsOutstanding>48623846</ns2:noOfUnitsOutstanding>
            <ns2:approxSaleDate>11/16/2023</ns2:approxSaleDate>
            <ns2:securitiesExchangeName>NASD</ns2:securitiesExchangeName>
        </ns2:securitiesInformation>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:acquiredDate>07/01/2021</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Vested Stock Award</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>1750</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>07/01/2021</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:acquiredDate>10/01/2021</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Vested Stock Award</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>1750</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>10/01/2021</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:acquiredDate>06/30/2023</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Vested Stock Award</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>1435</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>06/30/2023</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:acquiredDate>04/01/2022</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Vested Stock Award</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>1462</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>04/01/2022</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:acquiredDate>03/31/2023</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Vested Stock Award</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>1456</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>03/31/2023</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:acquiredDate>04/01/2021</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Vested Stock Award</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>1750</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>04/01/2021</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:acquiredDate>09/29/2023</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Vested Stock Award</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>1433</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>09/29/2023</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:acquiredDate>07/01/2022</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Vested Stock Award</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>1524</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>07/01/2022</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:acquiredDate>01/01/2023</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Vested Stock Award</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>1709</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>01/01/2023</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:acquiredDate>10/01/2020</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Vested Stock Award</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>1750</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>10/01/2023</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:acquiredDate>01/01/2021</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Vested Stock Award</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>1750</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>01/01/2021</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:securitiesToBeSold>
            <ns2:securitiesClassTitle>Common Stock</ns2:securitiesClassTitle>
            <ns2:acquiredDate>09/30/2022</ns2:acquiredDate>
            <ns2:natureOfAcquisitionTransaction>Vested Stock Award</ns2:natureOfAcquisitionTransaction>
            <ns2:nameOfPersonfromWhomAcquired>Issuer</ns2:nameOfPersonfromWhomAcquired>
            <ns2:isGiftTransaction>N</ns2:isGiftTransaction>
            <ns2:amountOfSecuritiesAcquired>231</ns2:amountOfSecuritiesAcquired>
            <ns2:paymentDate>09/30/2022</ns2:paymentDate>
            <ns2:natureOfPayment>Compensation</ns2:natureOfPayment>
        </ns2:securitiesToBeSold>
        <ns2:nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</ns2:nothingToReportFlagOnSecuritiesSoldInPast3Months>
        <ns2:remarks>all shares to be sold by Mr. David Blake Bath &amp; Mrs. Sydney Baird Bath Ten Ent</ns2:remarks>
        <ns2:noticeSignature>
            <ns2:noticeDate>11/16/2023</ns2:noticeDate>
            <ns2:planAdoptionDates/>
            <ns2:signature>Goldman Sachs &amp; Co. LLC on behalf of David Blake Bath</ns2:signature>
        </ns2:noticeSignature>
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[{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 10972}]
144
0001378530
XXXXXXXX
LIVE
0001158324
Cogent Communications Holdings, Inc.
000-51829
1015 31st Street
Washington
DC
20007
1-202-295-4200
David Blake Bath
Director
Common Stock
Goldman Sachs & Co. LLC
200 West Street
New York
NY
10282
18000
1197000
48623846
11/16/2023
NASD
Common Stock
07/01/2021
Vested Stock Award
Issuer
N
1750
07/01/2021
Compensation
Common Stock
10/01/2021
Vested Stock Award
Issuer
N
1750
10/01/2021
Compensation
Common Stock
06/30/2023
Vested Stock Award
Issuer
N
1435
06/30/2023
Compensation
Common Stock
04/01/2022
Vested Stock Award
Issuer
N
1462
04/01/2022
Compensation
Common Stock
03/31/2023
Vested Stock Award
Issuer
N
1456
03/31/2023
Compensation
Common Stock
04/01/2021
Vested Stock Award
Issuer
N
1750
04/01/2021
Compensation
Common Stock
09/29/2023
Vested Stock Award
Issuer
N
1433
09/29/2023
Compensation
Common Stock
07/01/2022
Vested Stock Award
Issuer
N
1524
07/01/2022
Compensation
Common Stock
01/01/2023
Vested Stock Award
Issuer
N
1709
01/01/2023
Compensation
Common Stock
10/01/2020
Vested Stock Award
Issuer
N
1750
10/01/2023
Compensation
Common Stock
01/01/2021
Vested Stock Award
Issuer
N
1750
01/01/2021
Compensation
Common Stock
09/30/2022
Vested Stock Award
Issuer
N
231
09/30/2022
Compensation
Y
all shares to be sold by Mr. David Blake Bath & Mrs. Sydney Baird Bath Ten Ent
11/16/2023
Goldman Sachs & Co. LLC on behalf of David Blake Bath