<?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>0001555186</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>



    </filerInfo>
  </headerData>
  <formData>
    <issuerInfo>
      <issuerCik>0001795815</issuerCik>
      <issuerName>California BanCorp \ CA</issuerName>
      <secFileNumber>001-41684</secFileNumber>
      <issuerAddress>
        <com:street1>12265 EL CAMINO REAL, SUITE 100</com:street1>
        <com:city>SAN DIEGO</com:city>
        <com:stateOrCountry>CA</com:stateOrCountry>
        <com:zipCode>92130</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>858-847-4787</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>Rainer David I</nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>
      <relationshipsToIssuer>
        <relationshipToIssuer>Director</relationshipToIssuer>
      </relationshipsToIssuer>
    </issuerInfo>
    <securitiesInformation>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <brokerOrMarketmakerDetails>
        <name>Wells Fargo Clearing Services</name>
        <address>
          <com:street1>One North Jefferson Avenue</com:street1>
          <com:city>St. Louis</com:city>
          <com:stateOrCountry>MO</com:stateOrCountry>
          <com:zipCode>63103</com:zipCode>
        </address>
      </brokerOrMarketmakerDetails>
      <noOfUnitsSold>7000</noOfUnitsSold>
      <aggregateMarketValue>102449.15</aggregateMarketValue>
      <noOfUnitsOutstanding>32412937</noOfUnitsOutstanding>
      <approxSaleDate>06/13/2025</approxSaleDate>
      <securitiesExchangeName>NASDAQ</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>03/01/2023</acquiredDate>
      <natureOfAcquisitionTransaction>Compensation</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>7000</amountOfSecuritiesAcquired>
      <paymentDate>03/01/2023</paymentDate>
      <natureOfPayment>N/A</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>Y</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <remarks>The 7,000 shares sold today were sold from the David and Anne Rainer Trust</remarks>
    <noticeSignature>
      <noticeDate>06/13/2025</noticeDate>
      <signature>David I Rainer</signature>
    </noticeSignature>
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144
0001555186
XXXXXXXX
LIVE
0001795815
California BanCorp \ CA
001-41684
12265 EL CAMINO REAL, SUITE 100
SAN DIEGO
CA
92130
858-847-4787
Rainer David I
Director
Common
Wells Fargo Clearing Services
One North Jefferson Avenue
St. Louis
MO
63103
7000
102449.15
32412937
06/13/2025
NASDAQ
Common
03/01/2023
Compensation
Issuer
N
7000
03/01/2023
N/A
Y
The 7,000 shares sold today were sold from the David and Anne Rainer Trust
06/13/2025
David I Rainer