content: <?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>0001183627</cik>
            <ccc>XXXXXXXX</ccc>
          </filerCredentials>
        </filer>
        <liveTestFlag>LIVE</liveTestFlag>
  
  
  
      </filerInfo>
    </headerData>
    <formData>
      <issuerInfo>
        <issuerCik>0001666134</issuerCik>
        <issuerName>BLACKLINE, INC.</issuerName>
        <secFileNumber>001-37924</secFileNumber>
        <issuerAddress>
          <com:street1>21300 VICTORY BOULEVARD</com:street1>
          <com:street2>12TH FLOOR</com:street2>
          <com:city>WOODLAND HILLS</com:city>
          <com:stateOrCountry>CA</com:stateOrCountry>
          <com:zipCode>91367</com:zipCode>
        </issuerAddress>
        <issuerContactPhone>818-223-9008</issuerContactPhone>
        <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>PRAGER MORGAN KAROLE</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
        <relationshipsToIssuer>
          <relationshipToIssuer>Officer</relationshipToIssuer>
        </relationshipsToIssuer>
      </issuerInfo>
      <securitiesInformation>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <brokerOrMarketmakerDetails>
          <name>Fidelity Brokerage Services LLC</name>
          <address>
            <com:street1>900 Salem Street</com:street1>
            <com:city>Smithfield</com:city>
            <com:stateOrCountry>RI</com:stateOrCountry>
            <com:zipCode>02917</com:zipCode>
          </address>
        </brokerOrMarketmakerDetails>
        <noOfUnitsSold>10007</noOfUnitsSold>
        <aggregateMarketValue>574887.79</aggregateMarketValue>
        <noOfUnitsOutstanding>61269812</noOfUnitsOutstanding>
        <approxSaleDate>02/20/2024</approxSaleDate>
        <securitiesExchangeName>NASDAQ</securitiesExchangeName>
      </securitiesInformation>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>08/20/2020</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>762</amountOfSecuritiesAcquired>
        <paymentDate>08/20/2020</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>11/20/2020</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>762</amountOfSecuritiesAcquired>
        <paymentDate>11/20/2020</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>02/20/2021</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>719</amountOfSecuritiesAcquired>
        <paymentDate>02/20/2021</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>05/20/2021</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>2838</amountOfSecuritiesAcquired>
        <paymentDate>05/20/2021</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>08/20/2021</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>1280</amountOfSecuritiesAcquired>
        <paymentDate>08/20/2021</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>11/20/2021</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>1280</amountOfSecuritiesAcquired>
        <paymentDate>11/20/2021</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>02/20/2022</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>1951</amountOfSecuritiesAcquired>
        <paymentDate>02/20/2022</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <securitiesToBeSold>
        <securitiesClassTitle>Common</securitiesClassTitle>
        <acquiredDate>05/20/2022</acquiredDate>
        <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
        <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
        <isGiftTransaction>N</isGiftTransaction>
        <amountOfSecuritiesAcquired>415</amountOfSecuritiesAcquired>
        <paymentDate>05/20/2022</paymentDate>
        <natureOfPayment>Compensation</natureOfPayment>
      </securitiesToBeSold>
      <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
      <noticeSignature>
        <noticeDate>02/20/2024</noticeDate>
        <planAdoptionDates>
          <planAdoptionDate>11/14/2023</planAdoptionDate>
        </planAdoptionDates>
        <signature>/s/ Andrew Glade, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Karole Morgan-Prager</signature>
      </noticeSignature>
    </formData>
  </edgarSubmission>
metadata_documents: [{"type": "144", "sequence": "1", "filename": "primary_doc.xml", "secsgml_size_bytes": 6766}]
text: 144
  0001183627
  XXXXXXXX
  LIVE
  0001666134
  BLACKLINE, INC.
  001-37924
  21300 VICTORY BOULEVARD
  12TH FLOOR
  WOODLAND HILLS
  CA
  91367
  818-223-9008
  PRAGER MORGAN KAROLE
  Officer
  Common
  Fidelity Brokerage Services LLC
  900 Salem Street
  Smithfield
  RI
  02917
  10007
  574887.79
  61269812
  02/20/2024
  NASDAQ
  Common
  08/20/2020
  Restricted Stock Vesting
  Issuer
  N
  762
  08/20/2020
  Compensation
  Common
  11/20/2020
  Restricted Stock Vesting
  Issuer
  N
  762
  11/20/2020
  Compensation
  Common
  02/20/2021
  Restricted Stock Vesting
  Issuer
  N
  719
  02/20/2021
  Compensation
  Common
  05/20/2021
  Restricted Stock Vesting
  Issuer
  N
  2838
  05/20/2021
  Compensation
  Common
  08/20/2021
  Restricted Stock Vesting
  issuer
  N
  1280
  08/20/2021
  Compensation
  Common
  11/20/2021
  Restricted Stock Vesting
  Issuer
  N
  1280
  11/20/2021
  Compensation
  Common
  02/20/2022
  Restricted Stock Vesting
  Issuer
  N
  1951
  02/20/2022
  Compensation
  Common
  05/20/2022
  Restricted Stock Vesting
  Issuer
  N
  415
  05/20/2022
  Compensation
  Y
  02/20/2024
  11/14/2023
  /s/ Andrew Glade, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for Karole Morgan-Prager