<?xml version="1.0"?>
<edgarSubmission>

    <schemaVersion>X0708</schemaVersion>

    <submissionType>D</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0002128628</cik>
        <entityName>Catchment Capital Iris Co-Invest Fund, L.P.</entityName>
        <issuerAddress>
            <street1>331 PARK AVENUE SOUTH</street1>
            <street2>10TH FLOOR</street2>
            <city>NEW YORK</city>
            <stateOrCountry>NY</stateOrCountry>
            <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
            <zipCode>10010</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>212-400-7300</issuerPhoneNumber>
        <jurisdictionOfInc>DELAWARE</jurisdictionOfInc>
        <edgarPreviousNameList>
            <previousName>Catchment Capital Iris Co-Invest, L.P.</previousName>
        </edgarPreviousNameList>
        <entityType>Limited Partnership</entityType>
        <yearOfInc>
            <withinFiveYears>true</withinFiveYears>
            <value>2026</value>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>N/A</firstName>
                <lastName>Catchment Capital Partners GP, L.P.</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>331 Park Avenue South</street1>
                <street2>10th Floor</street2>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                <zipCode>10010</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Promoter</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>The Issuer's General Partner</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>N/A</firstName>
                <lastName>Catchment Capital Partners UGP, LLC</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>331 Park Avenue South</street1>
                <street2>10th Floor</street2>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                <zipCode>10010</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Director</relationship>
                <relationship>Promoter</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>The Issuer's General Partner's General Partner</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Alexander</firstName>
                <middleName>Mark</middleName>
                <lastName>Rose</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>331 Park Avenue South</street1>
                <street2>10th Floor</street2>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                <zipCode>10010</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Promoter</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification></relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Pooled Investment Fund</industryGroupType>
            <investmentFundInfo>
                <investmentFundType>Private Equity Fund</investmentFundType>
                <is40Act>false</is40Act>
            </investmentFundInfo>
        </industryGroup>
        <issuerSize>
            <revenueRange>Not Applicable</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06b</item>
            <item>3C</item>
            <item>3C.1</item>
            <item>3C.7</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>false</isAmendment>
            </newOrAmendment>
            <dateOfFirstSale>
                <yetToOccur>true</yetToOccur>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>false</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isPooledInvestmentFundType>true</isPooledInvestmentFundType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
            <clarificationOfResponse></clarificationOfResponse>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>0</minimumInvestmentAccepted>
        <salesCompensationList>
            <recipient>
                <recipientName>REDE PARTNERS (AMERICAS) LLC</recipientName>
                <recipientCRDNumber>299631</recipientCRDNumber>
                <associatedBDName>None</associatedBDName>
                <associatedBDCRDNumber>None</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>1270 AVENUE OF THE AMERICAS</street1>
                    <street2>SUITE 408</street2>
                    <city>New York</city>
                    <stateOrCountry>NY</stateOrCountry>
                    <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                    <zipCode>10020</zipCode>
                </recipientAddress>
                <statesOfSolicitationList>
                    <state>AL</state>
                    <description>ALABAMA</description>
                    <state>AK</state>
                    <description>ALASKA</description>
                    <state>AZ</state>
                    <description>ARIZONA</description>
                    <state>CA</state>
                    <description>CALIFORNIA</description>
                    <state>CO</state>
                    <description>COLORADO</description>
                    <state>CT</state>
                    <description>CONNECTICUT</description>
                    <state>DE</state>
                    <description>DELAWARE</description>
                    <state>DC</state>
                    <description>DISTRICT OF COLUMBIA</description>
                    <state>FL</state>
                    <description>FLORIDA</description>
                    <state>GA</state>
                    <description>GEORGIA</description>
                    <state>HI</state>
                    <description>HAWAII</description>
                    <state>IL</state>
                    <description>ILLINOIS</description>
                    <state>IN</state>
                    <description>INDIANA</description>
                    <state>IA</state>
                    <description>IOWA</description>
                    <state>KY</state>
                    <description>KENTUCKY</description>
                    <state>LA</state>
                    <description>LOUISIANA</description>
                    <state>ME</state>
                    <description>MAINE</description>
                    <state>MD</state>
                    <description>MARYLAND</description>
                    <state>MA</state>
                    <description>MASSACHUSETTS</description>
                    <state>MI</state>
                    <description>MICHIGAN</description>
                    <state>MN</state>
                    <description>MINNESOTA</description>
                    <state>MO</state>
                    <description>MISSOURI</description>
                    <state>MT</state>
                    <description>MONTANA</description>
                    <state>NH</state>
                    <description>NEW HAMPSHIRE</description>
                    <state>NJ</state>
                    <description>NEW JERSEY</description>
                    <state>NM</state>
                    <description>NEW MEXICO</description>
                    <state>NY</state>
                    <description>NEW YORK</description>
                    <state>NC</state>
                    <description>NORTH CAROLINA</description>
                    <state>OH</state>
                    <description>OHIO</description>
                    <state>OR</state>
                    <description>OREGON</description>
                    <state>PA</state>
                    <description>PENNSYLVANIA</description>
                    <state>RI</state>
                    <description>RHODE ISLAND</description>
                    <state>SC</state>
                    <description>SOUTH CAROLINA</description>
                    <state>TN</state>
                    <description>TENNESSEE</description>
                    <state>TX</state>
                    <description>TEXAS</description>
                    <state>UT</state>
                    <description>UTAH</description>
                    <state>VA</state>
                    <description>VIRGINIA</description>
                    <state>WA</state>
                    <description>WASHINGTON</description>
                    <state>WV</state>
                    <description>WEST VIRGINIA</description>
                    <state>WI</state>
                    <description>WISCONSIN</description>
                </statesOfSolicitationList>
                <foreignSolicitation>false</foreignSolicitation>
            </recipient>
        </salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>Indefinite</totalOfferingAmount>
            <totalAmountSold>0</totalAmountSold>
            <totalRemaining>Indefinite</totalRemaining>
            <clarificationOfResponse></clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>0</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>0</dollarAmount>
                <isEstimate>true</isEstimate>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
                <isEstimate>true</isEstimate>
            </findersFees>
            <clarificationOfResponse></clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>0</dollarAmount>
                <isEstimate>true</isEstimate>
            </grossProceedsUsed>
            <clarificationOfResponse></clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>Catchment Capital Iris Co-Invest Fund, L.P.</issuerName>
                <signatureName>Alexander Mark Rose</signatureName>
                <nameOfSigner>Alexander Mark Rose</nameOfSigner>
                <signatureTitle>Managing Member of the GP of the Issuer's GP</signatureTitle>
                <signatureDate>2026-04-16</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
