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

    <schemaVersion>X0708</schemaVersion>

    <submissionType>D/A</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0002034263</cik>
        <entityName>New Stack III Q, L.P.</entityName>
        <issuerAddress>
            <street1>600 W JACKSON BLVD STE 100</street1>
            <city>CHICAGO</city>
            <stateOrCountry>IL</stateOrCountry>
            <stateOrCountryDescription>ILLINOIS</stateOrCountryDescription>
            <zipCode>60661</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>(312) 804-3306</issuerPhoneNumber>
        <jurisdictionOfInc>DELAWARE</jurisdictionOfInc>
        <issuerPreviousNameList>
            <value>None</value>
        </issuerPreviousNameList>
        <edgarPreviousNameList>
            <value>None</value>
        </edgarPreviousNameList>
        <entityType>Limited Partnership</entityType>
        <yearOfInc>
            <withinFiveYears>true</withinFiveYears>
            <value>2024</value>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Nicholas</firstName>
                <lastName>Moran</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>600 W Jackson Blvd., Suite 100</street1>
                <city>Chicago</city>
                <stateOrCountry>IL</stateOrCountry>
                <stateOrCountryDescription>ILLINOIS</stateOrCountryDescription>
                <zipCode>60661</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Managing Member of the General Partner</relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Pooled Investment Fund</industryGroupType>
            <investmentFundInfo>
                <investmentFundType>Venture Capital Fund</investmentFundType>
                <is40Act>false</is40Act>
            </investmentFundInfo>
        </industryGroup>
        <issuerSize>
            <revenueRange>Not Applicable</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06b</item>
            <item>3C</item>
            <item>3C.7</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>true</isAmendment>
                <previousAccessionNumber>0002034263-25-000001</previousAccessionNumber>
            </newOrAmendment>
            <dateOfFirstSale>
                <value>2024-08-29</value>
            </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>Innovation Partners LLC</recipientName>
                <recipientCRDNumber>146344</recipientCRDNumber>
                <associatedBDName>None</associatedBDName>
                <associatedBDCRDNumber>None</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>5950 Fairview Road, Suite 140</street1>
                    <city>Charlotte</city>
                    <stateOrCountry>NC</stateOrCountry>
                    <stateOrCountryDescription>NORTH CAROLINA</stateOrCountryDescription>
                    <zipCode>28210</zipCode>
                </recipientAddress>
                <statesOfSolicitationList>
                    <state>MN</state>
                    <description>MINNESOTA</description>
                    <state>MO</state>
                    <description>MISSOURI</description>
                    <state>IL</state>
                    <description>ILLINOIS</description>
                    <state>TX</state>
                    <description>TEXAS</description>
                    <state>IN</state>
                    <description>INDIANA</description>
                    <state>FL</state>
                    <description>FLORIDA</description>
                    <state>KS</state>
                    <description>KANSAS</description>
                    <state>NY</state>
                    <description>NEW YORK</description>
                    <state>CO</state>
                    <description>COLORADO</description>
                    <state>CT</state>
                    <description>CONNECTICUT</description>
                    <state>PA</state>
                    <description>PENNSYLVANIA</description>
                    <state>WI</state>
                    <description>WISCONSIN</description>
                    <state>MA</state>
                    <description>MASSACHUSETTS</description>
                    <state>AZ</state>
                    <description>ARIZONA</description>
                    <state>OH</state>
                    <description>OHIO</description>
                    <state>MI</state>
                    <description>MICHIGAN</description>
                    <state>NJ</state>
                    <description>NEW JERSEY</description>
                    <state>CA</state>
                    <description>CALIFORNIA</description>
                    <state>UT</state>
                    <description>UTAH</description>
                </statesOfSolicitationList>
                <foreignSolicitation>false</foreignSolicitation>
            </recipient>
        </salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>Indefinite</totalOfferingAmount>
            <totalAmountSold>14250000</totalAmountSold>
            <totalRemaining>Indefinite</totalRemaining>
            <clarificationOfResponse></clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>37</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>50000</dollarAmount>
                <isEstimate>true</isEstimate>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse></clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>0</dollarAmount>
            </grossProceedsUsed>
            <clarificationOfResponse></clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>New Stack III Q, L.P.</issuerName>
                <signatureName>/s/ J.R. Moran</signatureName>
                <nameOfSigner>J.R. Moran</nameOfSigner>
                <signatureTitle>Chief Operating Officer of the General Partner</signatureTitle>
                <signatureDate>2026-09-25</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
