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UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington , D.C. 20549 Form 10 - K ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31 , 2020 OR TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 ( d ) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from Delaware ( State or other jurisdiction of incorporation or organization ) 2001 Bryan Street , Suite 1600 Dallas , Texas ( Address of principal executive offices ) BUILDERS FIRSTSOURCE , INC . ( Exact name of registrant as specified in its charter ) Title of Each Class Common stock , par value $ 0.01 per share to Commission File Number : 0-51357 Large accelerated filer Emerging growth company Registrant's telephone number , including area code : ( 214 ) 880-3500 Securities registered pursuant to Section 12 ( b ) of the Act : Trading Symbol ( s ) . BLDR Securities registered pursuant to Section 12 ( g ) of the Act : None 52-2084569 ( I.R.S. Employer Identification No. ) No No ✔ Indicate by check mark if the registrant is a well - known seasoned issuer , as defined in Rule 405 of the Securities Act . Yes Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15 ( d ) of the Act . Yes Indicate by check mark whether the registrant ( 1 ) has filed all reports required to be filed by Section 13 or 15 ( d ) of the Securities Exchange Act of 1934 during the preceding 12 months ( or for such shorter period that the registrant was required to file such reports ) , and ( 2 ) has been subject to such filing requirements for the past 90 days . Yes No 75201 ( Zip Code ) Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S - T ( § 232.405 of this chapter ) during the preceding 12 months ( or for such shorter period that the registrant was required to submit such files ) . Yes No Accelerated filer Name of Each Exchange on Which Registered NASDAQ Stock Market LLC Indicate by check mark whether the registrant is a large accelerated filer , an accelerated filer , a non - accelerated filer , a smaller reporting company , or an emerging growth company . See the definitions of " large accelerated filer , ” “ accelerated filer , " " smaller reporting company , " and " emerging growth company " in Rule 12b - 2 of the Exchange Act . Non - accelerated filer Smaller reporting company If an emerging growth company , indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13 ( a ) of the Exchange Act . Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404 ( b ) of the Sarbanes - Oxley Act ( 15 U.S.C. 7262 ( b ) ) by the registered public accounting firm that prepared or issued its audit report . ✔ Indicate by check mark whether the registrant is a shell company ( as defined in Rule 12b - 2 of the Act ) . Yes No The aggregate market value of the registrant's common stock held by non - affiliates of the registrant as of June 30 , 2020 was approximately $ 2,375.5 million based on the closing price per share on that date of $ 20.70 as reported on the NASDAQ Stock Market LLC . The number of shares of the registrant's common stock , par value $ 0.01 , outstanding as of February 24 , 2021 was 206,431,681 . DOCUMENTS INCORPORATED BY REFERENCE Portions of the registrant's definitive proxy statement for its annual meeting of stockholders to be held on June 16 , 2021 are incorporated by reference into Part II and Part III of this Form 10 - K .