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

    <schemaVersion>X0708</schemaVersion>

    <submissionType>D/A</submissionType>

    <testOrLive>LIVE</testOrLive>

    <primaryIssuer>
        <cik>0002075726</cik>
        <entityName>Dauntless Ventures SBIC-B, L.P.</entityName>
        <issuerAddress>
            <street1>1895 E Rodeo Walk Drive</street1>
            <street2>Suite B200</street2>
            <city>Holladay</city>
            <stateOrCountry>UT</stateOrCountry>
            <stateOrCountryDescription>UTAH</stateOrCountryDescription>
            <zipCode>84117</zipCode>
        </issuerAddress>
        <issuerPhoneNumber>847-708-9360</issuerPhoneNumber>
        <jurisdictionOfInc>DELAWARE</jurisdictionOfInc>
        <issuerPreviousNameList>
            <value>None</value>
        </issuerPreviousNameList>
        <edgarPreviousNameList>
            <value>None</value>
        </edgarPreviousNameList>
        <entityType>Limited Partnership</entityType>
        <yearOfInc>
            <withinFiveYears>true</withinFiveYears>
            <value>2025</value>
        </yearOfInc>
    </primaryIssuer>

    <relatedPersonsList>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>N/A</firstName>
                <lastName>Dauntless Ventures SBIC GP, LLC</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>1895 E Rodeo Walk Drive</street1>
                <street2>Suite B200</street2>
                <city>Holladay</city>
                <stateOrCountry>UT</stateOrCountry>
                <stateOrCountryDescription>UTAH</stateOrCountryDescription>
                <zipCode>84117</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>General Partner of the Issuer</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Pete</firstName>
                <lastName>Koziol</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>1895 E Rodeo Walk Drive</street1>
                <street2>Suite B200</street2>
                <city>Holladay</city>
                <stateOrCountry>UT</stateOrCountry>
                <stateOrCountryDescription>UTAH</stateOrCountryDescription>
                <zipCode>84117</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Manager of the general partner of the Issuer</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Scott</firstName>
                <lastName>Robertson</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>1895 E Rodeo Walk Drive</street1>
                <street2>Suite B200</street2>
                <city>Holladay</city>
                <stateOrCountry>UT</stateOrCountry>
                <stateOrCountryDescription>UTAH</stateOrCountryDescription>
                <zipCode>84117</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Manager of the general partner of the Issuer</relationshipClarification>
        </relatedPersonInfo>
        <relatedPersonInfo>
            <relatedPersonName>
                <firstName>Mike</firstName>
                <lastName>Ferrari</lastName>
            </relatedPersonName>
            <relatedPersonAddress>
                <street1>1895 E Rodeo Walk Drive</street1>
                <street2>Suite B200</street2>
                <city>Holladay</city>
                <stateOrCountry>UT</stateOrCountry>
                <stateOrCountryDescription>UTAH</stateOrCountryDescription>
                <zipCode>84117</zipCode>
            </relatedPersonAddress>
            <relatedPersonRelationshipList>
                <relationship>Executive Officer</relationship>
            </relatedPersonRelationshipList>
            <relationshipClarification>Manager of the general partner of the Issuer</relationshipClarification>
        </relatedPersonInfo>
    </relatedPersonsList>

    <offeringData>
        <industryGroup>
            <industryGroupType>Pooled Investment Fund</industryGroupType>
            <investmentFundInfo>
                <investmentFundType>Venture Capital Fund</investmentFundType>
                <is40Act>false</is40Act>
            </investmentFundInfo>
        </industryGroup>
        <issuerSize>
            <revenueRange>Decline to Disclose</revenueRange>
        </issuerSize>
        <federalExemptionsExclusions>
            <item>3C.1</item>
            <item>06b</item>
            <item>3C</item>
        </federalExemptionsExclusions>
        <typeOfFiling>
            <newOrAmendment>
                <isAmendment>true</isAmendment>
                <previousAccessionNumber>0001123292-25-000404</previousAccessionNumber>
            </newOrAmendment>
            <dateOfFirstSale>
                <value>2025-09-10</value>
            </dateOfFirstSale>
        </typeOfFiling>
        <durationOfOffering>
            <moreThanOneYear>false</moreThanOneYear>
        </durationOfOffering>
        <typesOfSecuritiesOffered>
            <isEquityType>true</isEquityType>
            <isPooledInvestmentFundType>true</isPooledInvestmentFundType>
        </typesOfSecuritiesOffered>
        <businessCombinationTransaction>
            <isBusinessCombinationTransaction>false</isBusinessCombinationTransaction>
        </businessCombinationTransaction>
        <minimumInvestmentAccepted>0</minimumInvestmentAccepted>
        <salesCompensationList></salesCompensationList>
        <offeringSalesAmounts>
            <totalOfferingAmount>Indefinite</totalOfferingAmount>
            <totalAmountSold>16789500</totalAmountSold>
            <totalRemaining>Indefinite</totalRemaining>
            <clarificationOfResponse>The total offering amount of the issuer, along with Dauntless VC Fund I, L.P., Dauntless Ventures SBIC-A, L.P. and any of their respective feeder funds is $100,000,000. The Amount Sold for the Issuer includes amounts sold via Dauntless VC Fund I, L.P.</clarificationOfResponse>
        </offeringSalesAmounts>
        <investors>
            <hasNonAccreditedInvestors>false</hasNonAccreditedInvestors>
            <totalNumberAlreadyInvested>38</totalNumberAlreadyInvested>
        </investors>
        <salesCommissionsFindersFees>
            <salesCommissions>
                <dollarAmount>0</dollarAmount>
            </salesCommissions>
            <findersFees>
                <dollarAmount>0</dollarAmount>
            </findersFees>
        </salesCommissionsFindersFees>
        <useOfProceeds>
            <grossProceedsUsed>
                <dollarAmount>0</dollarAmount>
            </grossProceedsUsed>
            <clarificationOfResponse>The General Partner of the Issuer is entitled to carried interest. An affiliate of the General Partner of the Issuer is entitled to a management fee. The carried interest and management fee are set forth in the Issuer's governing agreement.</clarificationOfResponse>
        </useOfProceeds>
        <signatureBlock>
            <authorizedRepresentative>false</authorizedRepresentative>
            <signature>
                <issuerName>Dauntless Ventures SBIC-B, L.P.</issuerName>
                <signatureName>/s/ Pete Koziol</signatureName>
                <nameOfSigner>Pete Koziol</nameOfSigner>
                <signatureTitle>Authorized Person of the Issuer</signatureTitle>
                <signatureDate>2026-05-08</signatureDate>
            </signature>
        </signatureBlock>
    </offeringData>
</edgarSubmission>
