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

    <schemaVersion>X0708</schemaVersion>

    <submissionType>D</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0001848470</cik>
        <entityName>Insight Partners XII, L.P.</entityName>
        <issuerAddress>
            <street1>BOX 309, UGLAND HOUSE</street1>
            <city>GRAND CAYMAN</city>
            <stateOrCountry>E9</stateOrCountry>
            <stateOrCountryDescription>CAYMAN ISLANDS</stateOrCountryDescription>
            <zipCode>KY1-1104</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>(212) 230-9200</issuerPhoneNumber>
        <jurisdictionOfInc>CAYMAN ISLANDS</jurisdictionOfInc>
        <issuerPreviousNameList>
            <value>None</value>
        </issuerPreviousNameList>
        <edgarPreviousNameList>
            <value>None</value>
        </edgarPreviousNameList>
        <entityType>Limited Partnership</entityType>
        <yearOfInc>
            <withinFiveYears>true</withinFiveYears>
            <value>2021</value>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Jeffrey</firstName>
                <lastName>Horing</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>c/o Insight Venture Management, LLC</street1>
                <street2>1114 Avenue of the Americas, 36th Floor</street2>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                <zipCode>10036</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Sole Director and Authorized Officer of the general partner of the general partner of the issuer</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Blair</firstName>
                <lastName>Flicker</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>c/o Insight Venture Management, LLC</street1>
                <street2>1114 Avenue of the Americas, 36th Floor</street2>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                <zipCode>10036</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>General Counsel, Vice President and Authorized Officer of the general partner of the general partner of the issuer</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Deven</firstName>
                <lastName>Parekh</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>c/o Insight Venture Management, LLC</street1>
                <street2>1114 Avenue of the Americas, 36th Floor</street2>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                <zipCode>10036</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Vice President and Authorized Officer of the general partner of the general partner of the issuer</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Mark</firstName>
                <lastName>Lessing</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>c/o Insight Venture Management, LLC</street1>
                <street2>1114 Avenue of the Americas, 36th Floor</street2>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                <zipCode>10036</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Chief Financial Officer, Vice President and Authorized Officer of the general partner of the general partner of the issuer</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Andrew</firstName>
                <lastName>Prodromos</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>c/o Insight Venture Management, LLC</street1>
                <street2>1114 Avenue of the Americas, 36th Floor</street2>
                <city>New York</city>
                <stateOrCountry>NY</stateOrCountry>
                <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                <zipCode>10036</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
                <relationship>Director</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Alternate Director, Vice President and Authorized Officer of the general partner of the general partner of the issuer</relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Pooled Investment Fund</industryGroupType>
            <investmentFundInfo>
                <investmentFundType>Private Equity Fund</investmentFundType>
                <is40Act>false</is40Act>
            </investmentFundInfo>
        </industryGroup>
        <issuerSize>
            <revenueRange>Decline to Disclose</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>06b</item>
            <item>3C</item>
            <item>3C.7</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>false</isAmendment>
            </newOrAmendment>
            <dateOfFirstSale>
                <yetToOccur>true</yetToOccur>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>false</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isEquityType>true</isEquityType>
            <isPooledInvestmentFundType>true</isPooledInvestmentFundType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
            <clarificationOfResponse></clarificationOfResponse>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>0</minimumInvestmentAccepted>
        <salesCompensationList>
            <recipient>
                <recipientName>Warren H. Spar</recipientName>
                <recipientCRDNumber>2357369</recipientCRDNumber>
                <associatedBDName>Sparring Partners Capital LLC</associatedBDName>
                <associatedBDCRDNumber>133780</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>420 Lexington Avenue, Suite 2458</street1>
                    <city>New York</city>
                    <stateOrCountry>NY</stateOrCountry>
                    <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                    <zipCode>10170</zipCode>
                </recipientAddress>
                <statesOfSolicitationList>
                    <state>NJ</state>
                    <description>NEW JERSEY</description>
                    <state>NY</state>
                    <description>NEW YORK</description>
                    <state>PA</state>
                    <description>PENNSYLVANIA</description>
                    <state>UT</state>
                    <description>UTAH</description>
                </statesOfSolicitationList>
                <foreignSolicitation>false</foreignSolicitation>
            </recipient>
            <recipient>
                <recipientName>Magenta Capital Services Ltd.</recipientName>
                <recipientCRDNumber>None</recipientCRDNumber>
                <associatedBDName>Magenta Capital Services Ltd.</associatedBDName>
                <associatedBDCRDNumber>None</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>VICTORIA HOUSE</street1>
                    <street2>THE VALLEY</street2>
                    <city>ANGUILLA</city>
                    <stateOrCountry>D8</stateOrCountry>
                    <stateOrCountryDescription>VIRGIN ISLANDS, BRITISH</stateOrCountryDescription>
                    <zipCode>00000</zipCode>
                </recipientAddress>
                <statesOfSolicitationList></statesOfSolicitationList>
                <foreignSolicitation>true</foreignSolicitation>
            </recipient>
            <recipient>
                <recipientName>Fund Placement Israel Ltd.</recipientName>
                <recipientCRDNumber>None</recipientCRDNumber>
                <associatedBDName>Fund Placement Israel Ltd.</associatedBDName>
                <associatedBDCRDNumber>None</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>7 HASADOT</street1>
                    <city>RAMAT HASHARON</city>
                    <stateOrCountry>L3</stateOrCountry>
                    <stateOrCountryDescription>ISRAEL</stateOrCountryDescription>
                    <zipCode>4704351</zipCode>
                </recipientAddress>
                <statesOfSolicitationList></statesOfSolicitationList>
                <foreignSolicitation>true</foreignSolicitation>
            </recipient>
            <recipient>
                <recipientName>Evercore Group L.L.C.</recipientName>
                <recipientCRDNumber>42405</recipientCRDNumber>
                <associatedBDName>Evercore Group L.L.C.</associatedBDName>
                <associatedBDCRDNumber>42405</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>55 East 52nd Street</street1>
                    <city>New York</city>
                    <stateOrCountry>NY</stateOrCountry>
                    <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                    <zipCode>10055</zipCode>
                </recipientAddress>
                <statesOfSolicitationList>
                    <state>AL</state>
                    <description>ALABAMA</description>
                    <state>AK</state>
                    <description>ALASKA</description>
                    <state>AZ</state>
                    <description>ARIZONA</description>
                    <state>AR</state>
                    <description>ARKANSAS</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>ID</state>
                    <description>IDAHO</description>
                    <state>IL</state>
                    <description>ILLINOIS</description>
                    <state>IA</state>
                    <description>IOWA</description>
                    <state>KY</state>
                    <description>KENTUCKY</description>
                    <state>LA</state>
                    <description>LOUISIANA</description>
                    <state>MA</state>
                    <description>MASSACHUSETTS</description>
                    <state>MS</state>
                    <description>MISSISSIPPI</description>
                    <state>MT</state>
                    <description>MONTANA</description>
                    <state>NJ</state>
                    <description>NEW JERSEY</description>
                    <state>NY</state>
                    <description>NEW YORK</description>
                    <state>NC</state>
                    <description>NORTH CAROLINA</description>
                    <state>OH</state>
                    <description>OHIO</description>
                    <state>OK</state>
                    <description>OKLAHOMA</description>
                    <state>OR</state>
                    <description>OREGON</description>
                    <state>PA</state>
                    <description>PENNSYLVANIA</description>
                    <state>PR</state>
                    <description>PUERTO RICO</description>
                    <state>RI</state>
                    <description>RHODE ISLAND</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>
                </statesOfSolicitationList>
                <foreignSolicitation>true</foreignSolicitation>
            </recipient>
            <recipient>
                <recipientName>Mitsubishi: UFJ Alternative Investments Co., Ltd</recipientName>
                <recipientCRDNumber>None</recipientCRDNumber>
                <associatedBDName>Mitsubishi: UFJ Alternative Investments Co., Ltd</associatedBDName>
                <associatedBDCRDNumber>None</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>Hibiya Parkfront Bldg. 7F, 1-6</street1>
                    <street2>Uchisaiwaicho 2-Chome, Chiyoda-Ku</street2>
                    <city>Tokyo</city>
                    <stateOrCountry>M0</stateOrCountry>
                    <stateOrCountryDescription>JAPAN</stateOrCountryDescription>
                    <zipCode>100-0011</zipCode>
                </recipientAddress>
                <statesOfSolicitationList></statesOfSolicitationList>
                <foreignSolicitation>true</foreignSolicitation>
            </recipient>
            <recipient>
                <recipientName>HMC ITAJUBA</recipientName>
                <recipientCRDNumber>None</recipientCRDNumber>
                <associatedBDName>HMC ITAJUBA</associatedBDName>
                <associatedBDCRDNumber>None</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>Av. Nueva Costanera 4040</street1>
                    <street2>3rd floor, N 32,Vitacura</street2>
                    <city>Santiago</city>
                    <stateOrCountry>F3</stateOrCountry>
                    <stateOrCountryDescription>CHILE</stateOrCountryDescription>
                    <zipCode>00000</zipCode>
                </recipientAddress>
                <statesOfSolicitationList></statesOfSolicitationList>
                <foreignSolicitation>true</foreignSolicitation>
            </recipient>
            <recipient>
                <recipientName>David Choi</recipientName>
                <recipientCRDNumber>2277222</recipientCRDNumber>
                <associatedBDName>Sparring Partners Capital LLC</associatedBDName>
                <associatedBDCRDNumber>133780</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>420 Lexington Avenue, Suite 2458</street1>
                    <city>New York</city>
                    <stateOrCountry>NY</stateOrCountry>
                    <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                    <zipCode>10170</zipCode>
                </recipientAddress>
                <statesOfSolicitationList>
                    <state>MT</state>
                    <description>MONTANA</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>20000000</dollarAmount>
                <isEstimate>true</isEstimate>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse>The commission estimate includes amounts that may be payable in the next 12 months in connection with sales of interests in this Issuer and for the Issuer's parallel funds if specified amounts are invested.</clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>0</dollarAmount>
            </grossProceedsUsed>
            <clarificationOfResponse></clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>Insight Partners XII, L.P.</issuerName>
                <signatureName>Andrew Prodromos</signatureName>
                <nameOfSigner>Andrew Prodromos</nameOfSigner>
                <signatureTitle>See Item #3 above for Title</signatureTitle>
                <signatureDate>2021-04-28</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>