Matthew Trester - 15 Mar 2026 Form 4 Insider Report for Builders FirstSource, Inc. (BLDR)

Role: Principal Accounting Officer
Signature: /s/ Minator Azemi, by power of attorney
Issuer symbol: BLDR
Transactions as of: 15 Mar 2026
Net transactions value: $0
Form type: 4
Filing time: 17 Mar 2026, 19:05:07 UTC
Previous filing: 22 Apr 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Trester Matthew	Principal Accounting Officer	C/O BUILDERS FIRSTSOURCE, INC., 6031 CONNECTION DR., STE. 400, IRVING	/s/ Minator Azemi, by power of attorney	17 Mar 2026	0002043869

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	BLDR	Common Stock, par value $0.01 per share	Award		+1,419	+45%	$0.000000^*	4,579	15 Mar 2026	Direct	F1
transaction	BLDR	Common Stock, par value $0.01 per share	Award		+698	+15%	$0.000000^*	5,277	15 Mar 2026	Direct	F2
transaction	BLDR	Common Stock, par value $0.01 per share	Tax liability		-648	-12%	$88.09^*	4,629	15 Mar 2026	Direct	F3

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Reflects the acquisition of restricted stock units pursuant to the Corporation's 2014 Incentive Plan. The restricted stock units vest in 33.3% increments on each of March 15, 2027-2029 and entitle the reporting person to one share of common stock for each restricted stock unit that vests.
F2	Reflects the vesting of performance-based restricted stock units granted pursuant to the Corporation's 2014 Incentive Plan.
F3	Reflects shares withheld to pay tax withholding requirements on vesting of previously granted performance-based restricted stock units and restricted stock units.