<SEC-DOCUMENT>0000950170-25-078919.txt : 20250529
<SEC-HEADER>0000950170-25-078919.hdr.sgml : 20250529
<ACCEPTANCE-DATETIME>20250529160510
ACCESSION NUMBER:		0000950170-25-078919
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250527
FILED AS OF DATE:		20250529
DATE AS OF CHANGE:		20250529

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ALEXANDER MARK A
		CENTRAL INDEX KEY:			0001212607
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-40620
		FILM NUMBER:		251003252

	MAIL ADDRESS:	
		STREET 1:		C/O W. P. CAREY INC.
		STREET 2:		395 9TH AVENUE, 58TH FLOOR
		CITY:			NEW YORK, NEW YORK
		STATE:			NY
		ZIP:			10001

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Builders FirstSource, Inc.
		CENTRAL INDEX KEY:			0001316835
		STANDARD INDUSTRIAL CLASSIFICATION:	RETAIL-LUMBER & OTHER BUILDING MATERIALS DEALERS [5211]
		ORGANIZATION NAME:           	07 Trade & Services
		EIN:				522084569
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		6031 CONNECTION DR., STE. 400
		CITY:			IRVING
		STATE:			TX
		ZIP:			75039
		BUSINESS PHONE:		(214) 880-3500

	MAIL ADDRESS:	
		STREET 1:		6031 CONNECTION DR., STE. 400
		CITY:			IRVING
		STATE:			TX
		ZIP:			75039
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>ownership.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0508</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2025-05-27</periodOfReport>

    <issuer>
        <issuerCik>0001316835</issuerCik>
        <issuerName>Builders FirstSource, Inc.</issuerName>
        <issuerTradingSymbol>BLDR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001212607</rptOwnerCik>
            <rptOwnerName>ALEXANDER MARK A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O BUILDERS FIRSTSOURCE, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>6031 CONNECTION DR., STE. 400</rptOwnerStreet2>
            <rptOwnerCity>IRVING</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75039</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>true</isDirector>
            <isOfficer>false</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>false</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value $0.01 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2025-05-27</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1707</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>43854</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Reflects the acquisition of restricted stock units pursuant to the Corporation's 2014 Incentive Plan. The restricted stock units vest on May 27, 2026 and entitle the reporting person to one share of common stock for each restricted stock unit that vests.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Minator Azemi, by power of attorney</signatureName>
        <signatureDate>2025-05-29</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
