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

    <schemaVersion>X0708</schemaVersion>

    <submissionType>D</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0001805563</cik>
        <entityName>Sageview III (B), L.P.</entityName>
        <issuerAddress>
            <street1>55 RAILROAD AVENUE</street1>
            <city>GREENWICH</city>
            <stateOrCountry>CT</stateOrCountry>
            <stateOrCountryDescription>CONNECTICUT</stateOrCountryDescription>
            <zipCode>06830</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>203-625-4200</issuerPhoneNumber>
        <jurisdictionOfInc>CAYMAN ISLANDS</jurisdictionOfInc>
        <issuerPreviousNameList>
            <value>None</value>
        </issuerPreviousNameList>
        <edgarPreviousNameList>
            <previousName>Sageview Ill (B), L.P.</previousName>
        </edgarPreviousNameList>
        <entityType>Limited Partnership</entityType>
        <yearOfInc>
            <withinFiveYears>true</withinFiveYears>
            <value>2019</value>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Edward</firstName>
                <middleName>A.</middleName>
                <lastName>Gilhuly</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>245 Lytton Avenue, Suite 250</street1>
                <city>Palo Alto</city>
                <stateOrCountry>CA</stateOrCountry>
                <stateOrCountryDescription>CALIFORNIA</stateOrCountryDescription>
                <zipCode>94301</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Member of the Ultimate General Partner of the Issuer</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Scott</firstName>
                <middleName>M.</middleName>
                <lastName>Stuart</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>55 RAILROAD AVENUE</street1>
                <city>GREENWICH</city>
                <stateOrCountry>CT</stateOrCountry>
                <stateOrCountryDescription>CONNECTICUT</stateOrCountryDescription>
                <zipCode>06830</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Member of the Ultimate 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>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>100000</minimumInvestmentAccepted>
        <salesCompensationList>
            <recipient>
                <recipientName>Moelis &amp; Company LLC</recipientName>
                <recipientCRDNumber>145115</recipientCRDNumber>
                <associatedBDName>None</associatedBDName>
                <associatedBDCRDNumber>None</associatedBDCRDNumber>
                <recipientAddress>
                    <street1>399 PARK AVENUE, 5TH FLOOR</street1>
                    <city>NEW YORK</city>
                    <stateOrCountry>NY</stateOrCountry>
                    <stateOrCountryDescription>NEW YORK</stateOrCountryDescription>
                    <zipCode>10022</zipCode>
                </recipientAddress>
                <statesOfSolicitationList>
                    <value>All States</value>
                </statesOfSolicitationList>
                <foreignSolicitation>true</foreignSolicitation>
            </recipient>
        </salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>600000000</totalOfferingAmount>
            <totalAmountSold>0</totalAmountSold>
            <totalRemaining>600000000</totalRemaining>
            <clarificationOfResponse>Total Offering Amount applies to the Issuer and certain related entities.  Total Amount Sold applies to the Issuer only.  Total Remaining to be Sold may be sold by the Issuer and/or certain related entities.</clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>0</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>4500000</dollarAmount>
                <isEstimate>true</isEstimate>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
            <clarificationOfResponse>Sales Commissions represents an estimate of the total sales commissions to be paid to the entity listed in item 12 above over time as a result of the anticipated sales of interests in the Issuer and/or certain related entities.</clarificationOfResponse>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>0</dollarAmount>
            </grossProceedsUsed>
            <clarificationOfResponse>Customary management fees will be paid to Sageview Capital LP, an entity ultimately controlled by certain individuals listed in Item 3 above.</clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>Sageview III (B), L.P.</issuerName>
                <signatureName>/s/ Dino Verardo</signatureName>
                <nameOfSigner>Dino Verardo</nameOfSigner>
                <signatureTitle>Vice President of the Ultimate General Partner of the Issuer</signatureTitle>
                <signatureDate>2020-03-09</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
