Exhibit 4.1

Execution Version

SUPPLEMENTAL INDENTURE NO. 1

SUPPLEMENTAL INDENTURE NO. 1 (this “Supplemental Indenture”), dated as of July 1, 2026, among QXO Building Products, Inc., a Delaware corporation (the “Issuer”), the Subsidiary Guarantors listed on the signature pages hereto (the “Subsidiary Guarantors”) and Wilmington Trust, National Association, a national banking association, as trustee under the indenture referred to below (the “Trustee”).

W I T N E S S E T H :

WHEREAS, the Issuer and the Trustee have heretofore executed an indenture, dated as of June 17, 2026 (as amended, supplemented or otherwise modified, the “Indenture”), providing for the issuance of 6.500% Senior Notes due 2031 (the “2031 Notes”), initially in the aggregate principal amount of $1,500,000,000, and 6.875% Senior Notes due 2034 (the “2034 Notes” and, together with the 2031 Notes, the “Notes”), initially in the aggregate principal amount of $1,500,000,000;

WHEREAS, Section 4.11 of the Indenture provides that upon the consummation of the TopBuild Acquisition, each Subsidiary Guarantor shall immediately execute and deliver to the Trustee a supplemental indenture pursuant to which each Subsidiary Guarantor will provide a Subsidiary Guarantee in respect of the Issuer’s obligations under the Indenture and the Notes; and

WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee, the Issuer and the Subsidiary Guarantors are authorized to execute and deliver this Supplemental Indenture.

NOW, THEREFORE, in consideration of the foregoing and for other good and valuable consideration, the receipt of which is hereby acknowledged, the Issuer, the Subsidiary Guarantors and the Trustee mutually covenant and agree for the equal and ratable benefit of the holders of the Notes as follows:

1.            Defined Terms. As used in this Supplemental Indenture, terms defined in the Indenture or in the preamble or recital hereto are used herein as therein defined, except that the term “holders” in this Supplemental Indenture shall refer to the term “holders” as defined in the Indenture and the Trustee acting on behalf of and for the benefit of such holders. The words “herein,” “hereof” and “hereby” and other words of similar import used in this Supplemental Indenture refer to this Supplemental Indenture as a whole and not to any particular Section hereof.

2.            [Intentionally Omitted].

3.            Agreement to Guarantee. Each of the Subsidiary Guarantors hereby agrees, jointly and severally, to unconditionally guarantee the Issuer’s Obligations under the Notes and the Indenture on the terms and subject to the conditions set forth in Article XII of the Indenture and to be bound by all other applicable provisions of the Indenture and the Notes and to perform all of the obligations and agreements of a Subsidiary Guarantor under the Indenture.

4.            Notices. All notices or other communications to the Issuer and each of the Subsidiary Guarantors shall be given as provided in Section 14.02 of the Indenture.

5.            Ratification of Indenture; Supplemental Indentures Part of Indenture. Except as expressly amended hereby, the Indenture is in all respects ratified and confirmed and all the terms, conditions and provisions thereof shall remain in full force and effect. This Supplemental Indenture shall form a part of the Indenture for all purposes, and every holder of Notes heretofore or hereafter authenticated and delivered shall be bound hereby.

6.            Governing Law. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

7.            Trustee Makes No Representation. The Trustee makes no representation as to the validity or sufficiency of this Supplemental Indenture or to statements made in the recitals.

8.            Counterparts. This Supplemental Indenture may be executed electronically and in any number of counterparts, each of which shall be deemed to be an original, but all such counterparts shall together constitute one and the same Supplemental Indenture. One signed copy is enough to prove this Supplemental Indenture. Delivery of an executed counterpart of a signature page to this Supplemental Indenture by telecopier, facsimile, email or other electronic transmission (i.e., a “pdf” or “tif”) (including any electronic signature complying with the New York Electronic Signatures and Records Act (N.Y. State Tech. §§ 301-309), as amended from time to time, or other applicable law) shall be effective as delivery of a manually executed counterpart thereof.

9.            Effect of Headings. The Section headings herein are for convenience only and shall not affect the construction thereof.

[Remainder of page intentionally left blank.]

IN WITNESS WHEREOF, the parties have caused this Supplemental Indenture to be duly executed as of the date first written above.

[Signature Page to Supplemental Indenture No. 1]

[Signature Page to Supplemental Indenture No. 1]

[Signature Page to Supplemental Indenture No. 1]

[Signature Page to Supplemental Indenture No. 1]

[Signature Page to Supplemental Indenture No. 1]