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



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    <issuerInfo>
      <issuerCik>0001278021</issuerCik>
      <issuerName>MARKETAXESS HOLDINGS INC</issuerName>
      <secFileNumber>001-34091</secFileNumber>
      <issuerAddress>
        <com:street1>55 HUDSON YARDS, 15TH FLOOR</com:street1>
        <com:city>NEW YORK</com:city>
        <com:stateOrCountry>NY</com:stateOrCountry>
        <com:zipCode>10001</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>212-831-6000</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>McPherson Kevin M</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Officer</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Charles Schwab &amp; Co., Inc.</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>920</noOfUnitsSold>
      <aggregateMarketValue>239656.00</aggregateMarketValue>
      <noOfUnitsOutstanding>37905448</noOfUnitsOutstanding>
      <approxSaleDate>12/08/2023</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>01/31/2020</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Lapse</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>MARKETAXESS HOLDINGS INC</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>222</amountOfSecuritiesAcquired>
      <paymentDate>01/31/2020</paymentDate>
      <natureOfPayment>Equity Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>01/31/2022</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Lapse</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>MARKETAXESS HOLDINGS INC</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>698</amountOfSecuritiesAcquired>
      <paymentDate>01/31/2022</paymentDate>
      <natureOfPayment>Equity Compensation</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Kevin M McPherson</name>
        <address>
          <com:street1>55 HUDSON YARDS, 15TH FLOOR</com:street1>
          <com:city>NEW YORK</com:city>
          <com:stateOrCountry>NY</com:stateOrCountry>
          <com:zipCode>10001</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>MARKETAXESS HOLDINGS INC</securitiesClassTitle>
      <saleDate>11/27/2023</saleDate>
      <amountOfSecuritiesSold>1020</amountOfSecuritiesSold>
      <grossProceeds>235565.00</grossProceeds>
    </securitiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>12/08/2023</noticeDate>
      <signature>Kevin M McPherson</signature>
    </noticeSignature>
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144
0001704380
XXXXXXXX
LIVE
0001278021
MARKETAXESS HOLDINGS INC
001-34091
55 HUDSON YARDS, 15TH FLOOR
NEW YORK
NY
10001
212-831-6000
McPherson Kevin M
Officer
Common
Charles Schwab & Co., Inc.
3000 Schwab Way
Westlake
TX
76262
920
239656.00
37905448
12/08/2023
NASDAQ
Common
01/31/2020
Restricted Stock Lapse
MARKETAXESS HOLDINGS INC
N
222
01/31/2020
Equity Compensation
Common
01/31/2022
Restricted Stock Lapse
MARKETAXESS HOLDINGS INC
N
698
01/31/2022
Equity Compensation
N
Kevin M McPherson
55 HUDSON YARDS, 15TH FLOOR
NEW YORK
NY
10001
MARKETAXESS HOLDINGS INC
11/27/2023
1020
235565.00
12/08/2023
Kevin M McPherson