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    <submissionType>144</submissionType>
    <filerInfo>
      <filer>
        <filerCredentials>
          <cik>0001691591</cik>
          <ccc>XXXXXXXX</ccc>
        </filerCredentials>
      </filer>
      <liveTestFlag>LIVE</liveTestFlag>



    </filerInfo>
  </headerData>
  <formData>
    <issuerInfo>
      <issuerCik>0001020569</issuerCik>
      <issuerName>IRON MOUNTAIN INC</issuerName>
      <secFileNumber>001-13045</secFileNumber>
      <issuerAddress>
        <com:street1>85 NEW HAMPSHIRE AVENUE, SUITE 150</com:street1>
        <com:street2>PEASE INTERNATIONAL TRADEPORT</com:street2>
        <com:city>PORTSMOUTH</com:city>
        <com:stateOrCountry>NH</com:stateOrCountry>
        <com:zipCode>03801</com:zipCode>
      </issuerAddress>
      <issuerContactPhone>617-535-4781</issuerContactPhone>
      <nameOfPersonForWhoseAccountTheSecuritiesAreToBeSold>MARSON DEBORAH</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>1125</noOfUnitsSold>
      <aggregateMarketValue>60435.00</aggregateMarketValue>
      <noOfUnitsOutstanding>290896121</noOfUnitsOutstanding>
      <approxSaleDate>03/08/2023</approxSaleDate>
      <securitiesExchangeName>NYSE</securitiesExchangeName>
    </securitiesInformation>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>11/14/2014</acquiredDate>
      <natureOfAcquisitionTransaction>Dividend Reinvestment</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>17</amountOfSecuritiesAcquired>
      <paymentDate>11/14/2014</paymentDate>
      <natureOfPayment>Cash</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>02/15/2020</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>1047</amountOfSecuritiesAcquired>
      <paymentDate>02/15/2020</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <securitiesToBeSold>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <acquiredDate>02/16/2020</acquiredDate>
      <natureOfAcquisitionTransaction>Restricted Stock Vesting</natureOfAcquisitionTransaction>
      <nameOfPersonfromWhomAcquired>Issuer</nameOfPersonfromWhomAcquired>
      <isGiftTransaction>N</isGiftTransaction>
      <amountOfSecuritiesAcquired>61</amountOfSecuritiesAcquired>
      <paymentDate>02/16/2020</paymentDate>
      <natureOfPayment>Compensation</natureOfPayment>
    </securitiesToBeSold>
    <nothingToReportFlagOnSecuritiesSoldInPast3Months>N</nothingToReportFlagOnSecuritiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Deborah Marson</name>
        <address>
          <com:street1>85 New Hampshire Avenue</com:street1>
          <com:street2>Suite 150</com:street2>
          <com:city>Portsmouth</com:city>
          <com:stateOrCountry>NH</com:stateOrCountry>
          <com:zipCode>03801</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>12/14/2022</saleDate>
      <amountOfSecuritiesSold>1125</amountOfSecuritiesSold>
      <grossProceeds>62043.75</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Deborah Marson</name>
        <address>
          <com:street1>85 New Hampshire Avenue</com:street1>
          <com:street2>Suite 150</com:street2>
          <com:city>Portsmouth</com:city>
          <com:stateOrCountry>NH</com:stateOrCountry>
          <com:zipCode>03801</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>01/11/2023</saleDate>
      <amountOfSecuritiesSold>1125</amountOfSecuritiesSold>
      <grossProceeds>56902.50</grossProceeds>
    </securitiesSoldInPast3Months>
    <securitiesSoldInPast3Months>
      <sellerDetails>
        <name>Deborah Marson</name>
        <address>
          <com:street1>85 New Hampshire Avenue</com:street1>
          <com:street2>Suite 150</com:street2>
          <com:city>Portsmouth</com:city>
          <com:stateOrCountry>NH</com:stateOrCountry>
          <com:zipCode>03801</com:zipCode>
        </address>
      </sellerDetails>
      <securitiesClassTitle>Common</securitiesClassTitle>
      <saleDate>02/24/2023</saleDate>
      <amountOfSecuritiesSold>1125</amountOfSecuritiesSold>
      <grossProceeds>58241.25</grossProceeds>
    </securitiesSoldInPast3Months>
    <noticeSignature>
      <noticeDate>03/08/2023</noticeDate>
      <planAdoptionDates>
        <planAdoptionDate>05/09/2022</planAdoptionDate>
      </planAdoptionDates>
      <signature>/s/Wade Moss, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for  Deborah Marson</signature>
    </noticeSignature>
  </formData>
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144
0001691591
XXXXXXXX
LIVE
0001020569
IRON MOUNTAIN INC
001-13045
85 NEW HAMPSHIRE AVENUE, SUITE 150
PEASE INTERNATIONAL TRADEPORT
PORTSMOUTH
NH
03801
617-535-4781
MARSON DEBORAH
Officer
Common
Fidelity Brokerage Services LLC
900 Salem Street
Smithfield
RI
02917
1125
60435.00
290896121
03/08/2023
NYSE
Common
11/14/2014
Dividend Reinvestment
Issuer
N
17
11/14/2014
Cash
Common
02/15/2020
Restricted Stock Vesting
Issuer
N
1047
02/15/2020
Compensation
Common
02/16/2020
Restricted Stock Vesting
Issuer
N
61
02/16/2020
Compensation
N
Deborah Marson
85 New Hampshire Avenue
Suite 150
Portsmouth
NH
03801
Common
12/14/2022
1125
62043.75
Deborah Marson
85 New Hampshire Avenue
Suite 150
Portsmouth
NH
03801
Common
01/11/2023
1125
56902.50
Deborah Marson
85 New Hampshire Avenue
Suite 150
Portsmouth
NH
03801
Common
02/24/2023
1125
58241.25
03/08/2023
05/09/2022
/s/Wade Moss, as a duly authorized representative of Fidelity Brokerage Services LLC, as attorney-in-fact for  Deborah Marson