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TABLE OF CONTENTS

As filed with the Securities and Exchange Commission on September 4, 2019

Registration No. 333-        

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

GMS INC.
(Exact name of registrant as specified in its charter)

Delaware
(State or other jurisdiction of
incorporation or organization) 46-2931287
(I.R.S. Employer
Identification No.)

100 Crescent Centre Parkway, Suite 800
Tucker, Georgia 30084
(800) 392-4619
(Address, including zip code, and telephone number, including
area code, of registrant's principal executive offices)

John C. Turner, Jr.
President and Chief Executive Officer
GMS Inc.
100 Crescent Centre Parkway, Suite 800
Tucker, Georgia 30084
(800) 392-4619
(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

William S. Ortwein
Kyle G. Healy
Alston & Bird LLP
One Atlantic Center
Atlanta, Georgia 30309
(404) 881-7000

Approximate date of commencement of proposed sale to the public:
From time to time on or after the effective date of this Registration Statement

           If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box.    o

           If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box.    ý

           If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.

           If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.    o

           If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.    ý

           If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.    o

           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.

Large accelerated filer ý Accelerated filer o Non-accelerated filer o Smaller reporting company o Emerging growth company o

           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 7(a)(2)(B) of the Securities Act.    o

CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities to be Registered	Amount to be Registered(1)	Proposed Maximum Aggregate Offering Price Per Share	Proposed Maximum Aggregate Offering Price	Amount of Registration Fee
Common Stock, par value $0.01 per share	(2)	(2)	(2)	(3)

(1)

Pursuant to Rule 416 under the Securities Act of 1933, as amended (the "Securities Act"), the common stock being registered hereunder includes such indeterminate number of shares of common stock as may be issuable with respect to the shares being registered hereunder as a result of any stock splits, stock dividends or similar transactions for which no consideration will be received by the registrant.

(2)

An indeterminate amount of shares of common stock to be offered at indeterminate prices from time to time is being registered pursuant to this registration statement.

(3)

In accordance with Rules 456(b) and 457(r) of the Securities Act, the registrant is deferring payment of all of the registration fee. Registration fees will be paid subsequently on a pay-as-you-go basis.

Prospectus

GMS Inc.

Common Stock

        The selling stockholders to be identified in supplements to this prospectus may, from time to time, offer and sell shares of the common stock of GMS Inc. We are not selling any shares of our common stock, and we will not receive any of the proceeds from the sale of shares of our common stock by the selling stockholders.

        The common stock may be offered or sold by the selling stockholders at fixed prices, at prevailing market prices at the time of sale or at prices related to prevailing market prices or at prices negotiated with purchasers, to or through underwriters, broker-dealers, agents, or through any other means described in this prospectus under "Plan of Distribution" and in supplements to this prospectus in connection with a particular offering of our common stock by the selling stockholders. The selling stockholders will bear all underwriting commissions and discounts, if any, attributable to the sales of shares. We will bear other costs, expenses and fees in connection with the registration of the shares.

        This prospectus describes the general manner in which common stock may be offered and sold by the selling stockholders. When the selling stockholders sell common stock under this prospectus, we will provide a prospectus supplement that will contain more specific information about the terms of that offering. Any prospectus supplement may also add to, update, modify or replace information contained in this prospectus. This prospectus may not be used to sell securities without a prospectus supplement identifying the selling stockholders and describing the method and terms and of the offering. We urge you to read carefully this prospectus, any accompanying prospectus supplement and any documents we incorporate by reference into this prospectus and any accompanying prospectus supplement before you make your investment decision.

        Our common stock is listed on the New York Stock Exchange under the symbol "GMS". The last reported sale price of our common stock on September 3, 2019 was $29.44 per share.

Investing in our common stock involves risk. You should carefully consider all of the information set forth in this prospectus, including the risk factors set forth under "Risk Factors" in our Annual Report on Form 10-K for the fiscal year ended April 30, 2019 filed with the Securities and Exchange Commission on June 27, 2019 (which document is incorporated by reference herein), as well as the risk factors and other information contained in any accompanying prospectus supplement and any related free writing prospectus and any documents we incorporate by reference into this prospectus and any accompanying prospectus supplement, before deciding to invest in our common stock. See "Incorporation by Reference".

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus is September 4, 2019.

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS	1
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS	2
OUR COMPANY	4
RISK FACTORS	5
USE OF PROCEEDS	6
SELLING STOCKHOLDERS	7
DESCRIPTION OF CAPITAL STOCK	8
PLAN OF DISTRIBUTION	12
LEGAL MATTERS	15
EXPERTS	15
INCORPORATION BY REFERENCE	15
WHERE YOU CAN FIND MORE INFORMATION	16

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ABOUT THIS PROSPECTUS

        This prospectus is part of an "automatic shelf" registration statement on Form S-3 that we filed with the Securities and Exchange Commission (the "SEC"), as a "well-known seasoned issuer" as defined in Rule 405 under the Securities Act of 1933, as amended (the "Securities Act"), using the SEC's "shelf" registration rules. Pursuant to this prospectus, the selling stockholders may, from time to time, sell shares of our common stock in one or more offerings.

        This prospectus has been filed on behalf of the selling stockholders to be identified in supplements to this prospectus using a continuous offering process. Under the continuous offering process, the selling stockholders may, from time to time until the registration statement is withdrawn by us or expires, sell the common stock offered pursuant to this prospectus in one or more offerings. When the selling stockholders offer common stock under this prospectus, we will provide a prospectus supplement that will contain specific information about the terms of that offering. That prospectus supplement may include a discussion of any risk factors or other special considerations that apply to that offering. Any prospectus supplement may also add to, update, modify or replace information contained in this prospectus. If there is any inconsistency between the information in this prospectus and any prospectus supplement, you should rely on the information in that prospectus supplement. You should carefully read both this prospectus and any prospectus supplement together with the additional information described under the heading "Incorporation by Reference".

        This prospectus contains summaries of certain provisions contained in some of the documents described herein, but reference is hereby made to the actual documents for complete information. All of the summaries are qualified in their entirety by reference to the actual documents. Copies of some of the documents referred to herein have been filed or will be filed or incorporated by reference as exhibits to the registration statement of which this prospectus is a part, and you may obtain copies of those documents as described below in the section entitled "Where You Can Find More Information".

You should rely only on the information provided in this prospectus, including information incorporated by reference in this prospectus as described above, or any prospectus supplement or free writing prospectus that we have specifically referred you to. We have not authorized any other person to provide you with different information. If anyone provides you with different or inconsistent information, you should not rely on it. The selling stockholders will not make an offer to sell securities in any jurisdiction where the offer or sale is not permitted. You should not assume that the information in this prospectus, any accompanying prospectus supplement or any documents we incorporate by reference into this prospectus and any prospectus supplement is accurate as of any date other than the date on the front of those documents. Our business, financial condition, results of operations and prospects may have changed since those dates. Except as required by law, we do not undertake any obligation to update or revise, or to publicly announce any update or revision to, any of the forward-looking statements, whether as a result of new information, future events or otherwise, after the date of this prospectus.

        No action is being taken in any jurisdiction outside the United States to permit a public offering of common stock or possession or distribution of this prospectus in that jurisdiction. Persons who come into possession of this prospectus in jurisdictions outside the United States are required to inform themselves about and to observe any restriction as to this offering and the distribution of this prospectus applicable to those jurisdictions.

        References in this prospectus to the "Company," "GMS," "we," "us" and "our" and similar terms refer to GMS Inc. and its consolidated subsidiaries.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

        This prospectus and the documents incorporated by reference herein contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, Section 27A of the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). You can generally identify forward-looking statements by our use of forward-looking terminology such as "anticipate," "believe," "continue," "could," "estimate," "expect," "intend," "may," "might," "plan," "potential," "predict," "seek," or "should," or the negative thereof or other variations thereon or comparable terminology. In particular, statements about the markets in which we operate, including growth of our various markets, and statements about our expectations, beliefs, plans, strategies, objectives, prospects, assumptions or future events or performance contained or incorporated by reference in this prospectus are forward-looking statements.

        We have based these forward-looking statements on our current expectations, assumptions, estimates and projections. While we believe these expectations, assumptions, estimates and projections are reasonable, such forward-looking statements are only predictions and involve known and unknown risks and uncertainties, many of which are beyond our control. These and other important factors, including those discussed or incorporated by reference in this prospectus may cause our actual results, performance or achievements to differ materially from any future results, performance or achievements expressed or implied by these forward-looking statements. Some of the factors that could cause actual results to differ materially from those expressed or implied by the forward-looking statements include:

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general economic and financial conditions;

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our dependency upon the commercial and residential construction and residential repair and remodeling, or R&R, markets;

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competition in our highly fragmented industry and the markets in which we operate;

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the fluctuations in prices of the products we distribute;

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the consolidation of our industry;

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our ability to successfully implement our strategic initiatives, including our growth strategies and cost reduction initiatives;

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our ability to open new branches and expand into new geographic markets;

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our ability to successfully identify acquisition candidates, complete and integrate acquisitions and realize anticipated benefits and synergies from completed acquisitions;

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product shortages and potential loss of relationships with key suppliers;

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the seasonality of the commercial and residential construction markets;

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the potential loss of any significant customers;

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exposure to product liability and various other claims and litigation;

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our ability to attract and retain key employees;

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rising health care costs and labor costs, including the impact of labor and trucking shortages;

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the reduction of the quantity of products our customers purchase;

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the credit risk from our customers;

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our ability to renew leases for our facilities on favorable terms or identify new facilities;

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our ability to effectively manage our inventory as our sales volume increases or the prices of the products we distribute fluctuate;

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an impairment of our goodwill or intangible assets;

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the impact of federal, state, provincial and local regulations;

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the cost of compliance with environmental, health and safety laws and other regulations;

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significant increases in fuel costs or shortages in the supply of fuel;

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a cybersecurity breach, including misappropriation of our customers', employees' or suppliers' confidential information, and the potential costs related thereto;

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a disruption in our IT systems and costs necessary to maintain and update our IT systems;

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natural or man-made disruptions to our facilities;

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our exposure to greater than anticipated tax liabilities;

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the risk of our foreign operations, including currency rate fluctuations;

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the imposition of tariffs and other trade barriers, and the effect of retaliatory trade measures;

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our inability to engage in activities that may be in our best long-term interests because of restrictions in our debt agreements;

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our current level of indebtedness and our potential to incur additional indebtedness;

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our ability to obtain additional financing on acceptable terms, if at all;

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our holding company structure;

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the influence of AEA Investors LP and certain affiliates thereof on us;

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future sales of our common stock; and

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other risks and uncertainties, including those listed under "Risk Factors" in Part 1, Item 1A of our Annual Report on Form 10-K for the fiscal year ended April 30, 2019, as well as other risk factors described under the caption "Risk Factors" in any accompanying prospectus supplement and other reports we file with the SEC.

        Given these risks and uncertainties, you are cautioned not to place undue reliance on such forward-looking statements. The forward-looking statements contained or incorporated by reference in this prospectus are not guarantees of future performance and our actual results of operations, financial condition and liquidity, and the development of the industry in which we operate, may differ materially from the forward-looking statements contained or incorporated by reference in this prospectus. In addition, even if our results of operations, financial condition and liquidity, and events in the industry in which we operate, are consistent with the forward-looking statements contained or incorporated by reference in this prospectus, they may not be predictive of results or developments in future periods.

        Any forward-looking statement included or incorporated by reference in this prospectus speaks only as of the date of such statement. Except as required by law, we do not undertake any obligation to update or revise, or to publicly announce any update or revision to, any of the forward-looking statements, whether as a result of new information, future events or otherwise, after the date of this prospectus.

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OUR COMPANY

        Founded in 1971, we are a distributor of specialty building products including wallboard, suspended ceilings systems, or ceilings, steel framing and other complementary specialty building products. We purchase products from a large number of manufacturers and then distribute these goods to a customer base consisting of wallboard and ceilings contractors and homebuilders and, to a lesser extent, general contractors and individuals. We operate a network of more than 250 distribution centers across the United States and Canada.

        GMS Inc. is a Delaware corporation. Our principal executive office is located at 100 Crescent Centre Parkway, Suite 800, Tucker, Georgia 30084, and our telephone number at that address is (800) 392-4619. We maintain a website at www.gms.com. The information contained on, or that can be accessed through, our website is not a part of, and should not be considered as being incorporated by reference in this prospectus.

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RISK FACTORS

        Investing in our common stock involves a high degree of risk. Before deciding to invest in shares of our common stock, you should carefully consider the risks set forth under "Risk Factors" in our Annual Report on Form 10-K for the fiscal year ended April 30, 2019, filed with the SEC on June 27, 2019 (which document is incorporated by reference herein), as well as other risk factors described under the caption "Risk Factors" in any accompanying prospectus supplement and any documents we incorporate by reference into this prospectus, including all future filings we make with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act. See "Incorporation by Reference" and "Where You Can Find More Information." See also the information contained under the heading "Cautionary Note Regarding Forward-Looking Statements" above. The trading price of our common stock could decline due to any of these risks, and you may lose all or part of your investment in our common stock.

5

USE OF PROCEEDS

        The selling stockholders will receive all of the net proceeds from any sales pursuant to this prospectus.

        We will not receive any proceeds from the sale of shares of our common stock offered by the selling stockholders. We will, however, bear the costs associated with the sale of shares by the selling stockholders, other than any underwriting commissions and discounts, which will be borne by the selling stockholders.

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SELLING STOCKHOLDERS

        We may register shares of common stock covered by this prospectus for re-offers and resales by any selling stockholder to be named in a prospectus supplement. Since we are a well-known seasoned issuer, as defined in Rule 405 of the Securities Act, we may add secondary sales of our common stock by any selling shareholder by filing a prospectus supplement to this prospectus with the SEC. We may register these shares to permit selling stockholders to resell their shares when they deem appropriate. A selling stockholder may resell all, a portion or none of such stockholder's shares at any time and from time to time. The selling stockholders may not sell any of our common stock pursuant to this prospectus until we have identified such selling stockholders and the shares being offered for resale by such selling stockholders in a subsequent prospectus supplement. Selling stockholders may also sell, transfer or otherwise dispose of some or all of their common stock in transactions exempt from the registration requirements of the Securities Act. We do not know when or in what amounts the selling stockholders may offer shares for sale under this prospectus and any prospectus supplement. We will not receive any proceeds from any sale of shares by a selling stockholder under this prospectus and any prospectus supplement. We will bear the costs associated with the sale of shares by the selling stockholders, other than underwriting commissions and discounts, which will be borne by the selling stockholders.

        The applicable prospectus supplement will also disclose whether any of the selling stockholders has held any position or office with, has been employed by or otherwise has had a material relationship with us during the three years prior to the date of the prospectus supplement.

        We will provide to the selling stockholders copies of this prospectus and any applicable prospectus supplement and will take certain other actions as are required to permit unrestricted sales of the common stock offered hereby.

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DESCRIPTION OF CAPITAL STOCK

The following summary of the terms of our capital stock is qualified in its entirety by reference to our second amended and restated certificate of incorporation and our amended and restated bylaws, copies of which are filed as exhibits to the registration statement of which this prospectus forms a part, and the Delaware General Corporation Law, or the DGCL. See "Where You Can Find More Information".

General

        Our authorized capital stock consists of 500,000,000 shares of common stock, par value $0.01 per share, and 50,000,000 shares of preferred stock, par value $0.01 per share. As of August 31, 2019, there were 41,639,363 outstanding shares of common stock (excluding 2,352,263 shares of our common stock issuable upon exercise of outstanding stock options and 316,911 shares of our common stock issuable upon the settlement of outstanding restricted stock units) and no outstanding shares of preferred stock. As of August 31, 2019, we had 19 stockholders of record.

Common Stock

        The holders of our common stock are entitled to the following rights, preferences and privileges:

        Holders of our common stock are entitled to one vote for each share held on all matters submitted to a vote of stockholders and do not have cumulative voting rights. An election of directors by our stockholders shall be determined by a plurality of the votes cast by the stockholders present in person or represented by proxy at the meeting and entitled to vote on the election. There will be no cumulative voting in the election of directors, which means that holders of a majority of the outstanding shares of common stock will be able to elect all of the directors, and holders of less than a majority of such shares will be unable to elect any director. Holders of common stock are entitled to be paid ratably any dividends as may be declared by our board of directors (in its sole discretion), subject to any preferential dividend rights of outstanding preferred stock (if any).

        In the event of our liquidation or dissolution, the holders of our common stock are entitled to receive ratably, in proportion to the number of shares held by them, the assets available for distribution to stockholders after the payment of all debts and other liabilities and subject to the prior rights (if any) of any outstanding preferred stock. Holders of our common stock have no preemptive or other rights to subscribe for additional shares. The shares of our outstanding common stock are not subject to further calls or assessments by us. There are no conversion or redemption rights or sinking fund provisions applicable to the shares of our common stock. The rights, preferences and privileges of holders of our common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of preferred stock that we may designate and issue in the future.

Preferred Stock

        Our preferred stock, if issued, may have priority over our common stock with respect to dividends and other distributions, including the distribution of our assets upon liquidation. To the extent permitted by law, our board of directors will have the authority, without further stockholder authorization, to issue from time to time shares of authorized preferred stock in one or more series and to fix the terms, powers (including voting powers), rights and preferences, variations and the restrictions and limitations thereof of each series. Although we have no present plans to issue any shares of preferred stock, the issuance of shares of preferred stock, or the issuance of rights to purchase such shares, could adversely affect the rights and powers, including voting rights, of the common stock, and could have the effect of delaying, deterring or preventing a change in control of us or an unsolicited acquisition proposal.

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Limitations on Directors' Liability

        Our second amended and restated certificate of incorporation and amended and restated bylaws contain provisions indemnifying our directors and officers to the fullest extent permitted by law. We have also entered into indemnification agreements with each of our directors which, in certain cases, are broader than the specific indemnification provisions provided for under Delaware law.

        In addition, to the fullest extent permitted by Delaware law, our second amended and restated certificate of incorporation provides that no director will be personally liable to us or our stockholders for monetary damages for breach of fiduciary duty as a director. The effect of this provision is to restrict our rights and the rights of our stockholders in derivative suits to recover monetary damages from a director for breach of fiduciary duty as a director, except that a director will be personally liable for:

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any breach of his or her duty of loyalty to us or our stockholders;

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acts or omissions not in good faith which involve intentional misconduct or a knowing violation of law;

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the payment of dividends or the redemption or purchase of stock in violation of the DGCL; or

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any transaction from which the director derived an improper personal benefit.

        This provision does not affect a director's liability under the federal securities laws.

        To the extent that our directors, officers and controlling persons are indemnified under the provisions of our second amended and restated certificate of incorporation, our amended and restated bylaws, the DGCL or contractual arrangements against liabilities arising under the Securities Act, we have been advised that in the opinion of the SEC, such indemnification is against public policy as expressed in the Securities Act and is therefore unenforceable.

Provisions of Our Second Amended and Restated Certificate of Incorporation, Amended and Restated Bylaws and Delaware Law that May Have an Anti-Takeover Effect

        The DGCL, our second amended and restated certificate of incorporation and our amended and restated bylaws contain provisions that could have the effect of delaying, deferring or discouraging another party from acquiring control of us. These provisions, which are summarized below, are expected to discourage coercive takeover practices and inadequate takeover bids. These provisions are also designed to encourage persons seeking to acquire control of us to first negotiate with our board of directors.

Staggered Board; Removal of Directors

        Our second amended and restated certificate of incorporation and our amended and restated bylaws divide our board of directors into three classes with staggered three-year terms. In addition, a director will be subject to removal by our stockholders only for cause and only by the affirmative vote of the holders of at least two-thirds in voting power of all of our then outstanding common stock. Any vacancy on our board of directors, including a vacancy resulting from an increase in the number of directors, may only be filled by vote of a majority of our directors then in office (subject to the rights of holders of any series of preferred stock or rights granted pursuant to the stockholders' agreement).

        Furthermore, our second amended and restated certificate of incorporation provides that the total number of directors may be changed only by the resolution of our board of directors (subject to the rights of holders of any series of preferred stock to elect additional directors). The classification of our board of directors and the limitations on the removal of directors, changes to the total numbers of

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directors and filling of vacancies could make it more difficult for a third party to acquire, or discourage a third party from seeking to acquire, control of our Company.

Stockholder Action by Written Consent; Special Meetings

        Our second amended and restated certificate of incorporation provides that any action required or permitted to be taken by our stockholders must be effected at a duly called annual or special meeting of the stockholders and may not be effected by written consent. Our second amended and restated certificate of incorporation and our amended and restated bylaws also provide that, except as otherwise required by law, special meetings of our stockholders can be called only by our chairman of the board or our board of directors.

Advance Notice Requirements for Stockholder Proposals

        Our amended and restated bylaws establish an advance notice procedure for stockholder proposals to be brought before an annual meeting of stockholders, including proposed nominations of persons for election to our board of directors. Stockholders at an annual meeting may only consider proposals or nominations specified in the notice of meeting or brought before the meeting by or at the direction of our board of directors or by a stockholder of record who is entitled to vote at the meeting and who has delivered timely written notice in proper form to our secretary of the stockholder's intention to bring such business before the meeting. These provisions could have the effect of delaying stockholder actions that are favored by the holders of a majority of our outstanding voting securities until the next stockholder meeting.

Section 203 of the Delaware General Corporation Law

        While we have opted out of Section 203 of the DGCL, our second amended and restated certificate of incorporation contains similar provisions providing that we may not engage in certain "business combinations" with any "interested stockholder" for a three-year period following the time that the stockholder became an interested stockholder, unless:

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prior to such time, our board of directors approved either the business combination or the transaction that resulted in the stockholder becoming an interested stockholder;

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upon consummation of the transaction that resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of our voting stock outstanding at the time the transaction commenced, excluding certain shares; or

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at or subsequent to that time, the business combination is approved by our board of directors and by the affirmative vote of holders of at least two-thirds of our outstanding voting stock that is not owned by the interested stockholder.

        Generally, a "business combination" includes a merger, asset or stock sale or other transaction provided for or through our Company resulting in a financial benefit to the interested stockholder. Subject to certain exceptions, an "interested stockholder" is a person who owns 15% or more of our outstanding voting stock and the affiliates and associates of such person. For purposes of this provision, "voting stock" means any class or series of stock entitled to vote generally in the election of directors.

        Under certain circumstances, this provision will make it more difficult for a person who qualifies as an "interested stockholder" to effect certain business combinations with our Company for a three-year period. This provision may encourage companies interested in acquiring us to negotiate in advance with our board of directors in order to avoid the stockholder approval requirement if our board of directors approves either the business combination or the transaction that results in the stockholder becoming an interested stockholder. These provisions also may have the effect of preventing changes in our board of

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directors and may make it more difficult to accomplish transactions that our stockholders may otherwise deem to be in their best interests.

        Our second amended and restated certificate of incorporation provides that certain affiliates of AEA Investors LP, their respective affiliates and any of their direct or indirect designated transferees (other than in certain market transfers and gifts) and any group of which such persons are a party do not constitute "interested stockholders" for purposes of this provision.

Amendments to Our Bylaws

        The DGCL provides generally that the affirmative vote of a majority of the shares present at any meeting and entitled to vote on a matter is required to amend a corporation's bylaws, unless a corporation's bylaws require a greater percentage. Our amended and restated bylaws may be amended or repealed by the affirmative vote of the holders of at least two-thirds of the voting power of all outstanding stock entitled to vote thereon, voting together as a single class.

Exclusive Forum

        Our second amended and restated certificate of incorporation provides that the Court of Chancery of the State of Delaware will be the sole and exclusive forum for (i) any derivative action or proceeding brought on our behalf, (ii) any action asserting a claim of breach of a fiduciary duty owed to us or our stockholders by any of our directors, officers or employees, (iii) any action asserting a claim against us arising under the DGCL, our second amended and restated certificate of incorporation or our amended and restated bylaws or (iv) any action asserting a claim against us that is governed by the internal affairs doctrine. Although we believe this provision benefits us by providing increased consistency in the application of Delaware law in the types of claims to which it applies, the provision may have the effect of discouraging lawsuits against our directors and officers and may limit our stockholders' ability to obtain a favorable judicial forum for disputes with us.

Stock Exchange Listing

        Our common stock is listed on the New York Stock Exchange under the symbol "GMS".

Transfer Agent and Registrar

        The transfer agent and registrar for our common stock is Broadridge Financial Solutions, Inc.

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PLAN OF DISTRIBUTION

General

        The selling stockholders may sell the shares of common stock covered by this prospectus from time to time using one or more of the following methods:

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underwritten public offerings;

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"at the market" sales to or through market makers or into an existing market for the securities;

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ordinary brokerage transactions and transactions in which the broker-dealer solicits purchasers;

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block trades in which the broker-dealer will attempt to sell the securities as agent but may position and resell a portion of the block as principal to facilitate the transaction;

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purchases by a broker-dealer as principal and resale by the broker-dealer for its account;

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privately negotiated transactions;

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short sales (including short sales "against the box");

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through the writing or settlement of standardized or over-the-counter options or other hedging or derivative transactions, whether through an options exchange or otherwise;

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by pledge to secure debts and other obligations;

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in other ways not involving market makers or established trading markets, including direct sales to purchasers or sales effected through agents;

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a combination of any such methods of sale; and

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any other method permitted pursuant to applicable law.

        To the extent required by law, this prospectus may be amended or supplemented from time to time to describe a specific plan of distribution. Any prospectus supplement relating to a particular offering of our common stock by the selling stockholders may include the following information to the extent required by law:

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the terms of the offering;

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the names of any underwriters, dealers or agents participating in the offering;

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the purchase price of the securities sold by the selling stockholders to any underwriter or dealer and the net proceeds expected to be received by the selling stockholders from the offering;

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any over-allotment options under which underwriters may purchase additional securities from the selling stockholders;

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any delayed delivery arrangements;

•

any agency fees or underwriting discounts and other items constituting agents' or underwriters' compensation;

•

any public offering price;

•

any discounts or concessions allowed or reallowed or paid to dealers; and

•

any securities exchange or market on which the securities may be listed.

        The selling stockholders may offer our common stock to the public through underwriting syndicates represented by managing underwriters or through underwriters without an underwriting syndicate. If underwriters are used for the sale of our common stock, the common stock will be

12

acquired by the underwriters for their own account. The underwriters may resell the common stock in one or more transactions, including in negotiated transactions at a fixed public offering price or at varying prices determined at the time of sale. In connection with any such underwritten sale of our common stock, underwriters may receive compensation from the selling stockholders in the form of discounts, concessions or commissions. Underwriters may sell the common stock to or through dealers, and the dealers may receive compensation in the form of discounts, concessions or commissions from the underwriters or commissions from the purchasers for whom they may act as agents. Such compensation may be in excess of customary discounts, concessions or commissions. Underwriting compensation will not exceed 8% for any offering under this registration statement.

        If the selling stockholders use an underwriter or underwriters to effectuate the sale of common stock, we and the selling stockholders will execute an underwriting agreement with those underwriters at the time of sale of those shares of common stock. To the extent required by law, the names of the underwriters will be set forth in the prospectus supplement used by the underwriters to sell those shares of common stock. Unless otherwise indicated in the prospectus supplement relating to a particular offering of our common stock, the obligations of the underwriters to purchase our common stock from the selling stockholders will be subject to customary conditions precedent and the underwriters will be obligated to purchase all of the shares of our common stock offered by the selling stockholders if any of the shares of common stock are purchased.

        In effecting sales, brokers or dealers engaged by us and the selling stockholders may arrange for other brokers or dealers to participate. Broker-dealers may receive discounts, concessions or commissions from the selling stockholders (or, if any broker-dealer acts as agent for the purchaser of shares, from the purchaser) in amounts to be negotiated. Such compensation may be in excess of customary discounts, concessions or commissions. If dealers are utilized in the sale of common stock, the names of the dealers and the terms of the transaction will be set forth in a prospectus supplement, if required.

        The selling stockholders may also sell our common stock from time to time through agents. The applicable prospectus supplement will name any agent involved in the offer or sale of such common stock and will list commissions payable to these agents if required. These agents will be acting on a best efforts basis to solicit purchases for the period of their appointment, unless otherwise stated in any required prospectus supplement.

        The selling stockholders may sell shares of our common stock directly to purchasers. In this case, the selling stockholders may not engage underwriters or agents in the offer and sale of such shares.

        Selling stockholders and any underwriters, broker-dealers or agents that participate in the sale of any such selling stockholders' common stock or interests therein may be "underwriters" within the meaning of the Securities Act. Any discounts, commissions, concessions or profit they earn on any resale of common stock may be underwriting discounts and commissions under the Securities Act. Selling stockholders who are "underwriters" within the meaning of the Securities Act will be subject to the prospectus delivery requirements of the Securities Act. We will make copies of this prospectus available to any selling stockholder for the purpose of satisfying the prospectus delivery requirements of the Securities Act, if applicable. If any entity is deemed an underwriter or any amounts are deemed underwriting discounts and commissions, the prospectus supplement will identify the underwriter or agent and describe the compensation received from any selling stockholder.

        From time to time, any selling stockholder may pledge, hypothecate or grant a security interest in some or all of the common stock owned by it. The pledgees, secured parties or persons to whom the shares have been hypothecated will, upon foreclosure, be deemed to be selling stockholders. The number of shares of a selling stockholder's common stock offered under this prospectus will decrease as and when it takes such actions. The plan of distribution for that selling stockholder's common stock will otherwise remain unchanged. In addition, a selling stockholder may, from time to time, sell short,

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and, in those instances, this prospectus may be delivered in connection with the short sales and the common stock offered under this prospectus may be used to cover short sales.

        Any selling stockholder may enter into hedging transactions with broker-dealers and the broker-dealers may engage in short sales of our common stock in the course of hedging the positions they assume with such selling stockholder, including, without limitation, in connection with distributions of common stock by those broker-dealers. Any selling stockholder may enter into option or other transactions with broker-dealers that involve the delivery of common stock offered hereby to the broker-dealers, who may then resell or otherwise transfer such shares of common stock.

        A selling stockholder that is an entity may elect to make a pro rata in-kind distribution of common stock to its members, partners or stockholders pursuant to the registration statement of which this prospectus is a part by delivering a prospectus with a plan of distribution. Such members, partners or stockholders would thereby receive freely tradeable shares of common stock pursuant to the distribution through a registration statement. To the extent a distributee is an affiliate of ours (or to the extent otherwise required by law), we may file a prospectus supplement in order to permit the distributees to use the prospectus to resell the common stock acquired in the distribution. A selling stockholder that is an individual may make gifts of common stock covered hereby. Such donees may use the prospectus to resell the common stock or, if required by law, we may file a prospectus supplement naming such donees.

        We are not aware of any plans, arrangements or understandings between any stockholder and any underwriter, broker-dealer or agent regarding the sale of our common stock by any stockholder. There can be no assurance that the selling stockholders will sell any or all of the shares of our common stock registered pursuant to the registration statement of which this prospectus or any applicable prospectus supplement forms a part. In addition, we cannot assure you that any selling stockholder will not transfer, devise or gift our common stock by other means not described in this prospectus. Moreover, the selling stockholders may also sell shares pursuant to Rule 144 under the Securities Act or other available exemptions from the registration requirements of the Securities Act rather than pursuant to this prospectus or any applicable prospectus supplement.

Indemnification

        We and the selling stockholders may enter into agreements under which underwriters, dealers and agents who participate in the distribution of our common stock may be entitled to indemnification by us and the selling stockholders against various liabilities, including liabilities under the Securities Act, and to contribution with respect to payments which the underwriters, dealers or agents may be required to make.

Price Stabilization and Short Positions

        If underwriters or dealers are used in the sale, until the distribution of the securities is completed, rules of the SEC may limit the ability of any underwriters to bid for and purchase the securities. As an exception to these rules, representatives of any underwriters are permitted to engage in transactions that stabilize the price of the securities. These transactions may consist of bids or purchases for the purpose of pegging, fixing or maintaining the price of the securities. If the underwriters create a short position in the securities in connection with the offering (that is, if they sell more securities than are set forth on the cover page of the prospectus supplement) the representatives of the underwriters may reduce that short position by purchasing securities in the open market.

        We make no representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of our common stock. In addition, we make no representation that the representatives of any underwriters will engage in these transactions or that these transactions, once commenced, will not be discontinued without notice.

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LEGAL MATTERS

        The validity of the shares of common stock offered hereby will be passed upon for us by Alston & Bird LLP, Atlanta, Georgia. Any underwriters will be advised about legal matters by their own counsel, which will be named in a prospectus supplement to the extent required by law.

EXPERTS

        Ernst & Young LLP, independent registered public accounting firm, has audited our consolidated financial statements included in our Annual Report on Form 10-K for the years ended April 30, 2019 and 2018, and for each of the two years in the period ended April 30, 2019, and the effectiveness of our internal control over financial reporting as of April 30, 2019, as set forth in their reports, which are incorporated by reference in this prospectus and elsewhere in the registration statement. Our financial statements are incorporated by reference in reliance on Ernst & Young LLP's reports, given on their authority as experts in accounting and auditing.

        The financial statements for the year ended April 30, 2017 incorporated in this prospectus by reference to the Annual Report on Form 10-K for the year ended April 30, 2019 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

INCORPORATION BY REFERENCE

        We "incorporate by reference" certain documents we have filed with the SEC, which means that we are disclosing important information to you by referring you to those documents. The information incorporated by reference is an important part of this prospectus, and any information contained in any document incorporated by reference in this prospectus will be deemed to be modified or superseded to the extent that a statement contained in this prospectus or in any other subsequently filed document that also is incorporated by reference in this prospectus modifies or supersedes that statement. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to be a part of this prospectus.

        You should read the information incorporated by reference because it is an important part of this prospectus. We incorporate by reference the documents listed below and any future filings made by us with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, other than any portions of the respective filings that are furnished under either Item 2.02 or Item 7.01 of any Current Report on Form 8-K (including exhibits related thereto) or other applicable SEC rules, rather than filed, prior to the termination of the offering under this prospectus:

•

our Annual Report on Form 10-K for the fiscal year ended April 30, 2019, filed with the SEC on June 27, 2019;

•

our Quarterly Report on Form 10-Q for the quarterly period ended July 31, 2019, filed with the SEC on August 29, 2019;

•

our Current Reports on Form 8-K, filed with the SEC on July 25, 2019 and August 5, 2019;

•

those portions of our Definitive Proxy Statement on Schedule 14A, filed with the SEC on August 27, 2019, which are incorporated by reference in our Annual Report on Form 10-K for the fiscal year ended April 30, 2019; and

•

the description of our common stock contained in our Registration Statement on Form 8-A, filed with the SEC on May 23, 2016, as supplemented by the "Description of Capital Stock" included in this prospectus and including all amendments and reports filed for the purpose of updating such description.

15

        We hereby undertake to provide without charge to each person, including any beneficial owner, to whom a copy of this prospectus is delivered, upon written or oral request of any such person, a copy of any and all of the information that has been incorporated by reference in this prospectus, other than exhibits to such documents, unless such exhibits have been specifically incorporated by reference thereto. Requests for such copies should be directed to our Investor Relations department, at the following address:

GMS Inc.
100 Crescent Centre Parkway, Suite 800
Tucker, Georgia 30084
Attention: Investor Relations
(800) 392-4619

WHERE YOU CAN FIND MORE INFORMATION

        We have filed with the SEC a registration statement on Form S-3, including exhibits and schedules, under the Securities Act with respect to the common stock offered hereby. As allowed by SEC rules, this prospectus, which constitutes a part of the registration statement, does not contain all of the information set forth in the registration statement or the exhibits and schedules that are part of the registration statement. For further information about us and our common stock, you should refer to the registration statement, including all amendments, supplements, schedules and exhibits filed as a part of the registration statement.

        Statements contained or incorporated by reference in this prospectus regarding the contents of any contract or any other document that is filed as an exhibit to the registration statement are not necessarily complete, and each such statement is qualified in all respects by reference to the full text of such contract or other document filed as an exhibit to the registration statement.

        We are subject to the information and reporting requirements of the Exchange Act and, in accordance therewith, file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public at the SEC's web site (http://www.sec.gov) and on the investor page of our website at investor.gms.com. You may also request copies of those documents, at no cost to you, by contacting us at the following address:

GMS Inc.
100 Crescent Centre Parkway, Suite 800
Tucker, Georgia 30084
Attention: Investor Relations
(800) 392-4619

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.    Other Expenses of Issuance and Distribution

        The following table sets forth the costs and expenses, other than selling or underwriting commissions and discounts, to be incurred by us in connection with the issuance and distribution of the common stock being registered hereby. Except as otherwise noted, the Registrant will pay all of the costs and expenses set forth in the following table. All amounts shown below are estimates:

	Amount
SEC registration fee	$	*
Printing and engraving expenses		**
Legal fees and expenses		**
Accounting fees and expenses		**
Transfer agent and registrar fees		**
Miscellaneous expenses		**
Total	$	**

*

Deferred in accordance with Rule 456(b) and Rule 457(r) of the Securities Act and will be paid at the time of any particular offering of securities under this registration statement.

**

Since an indeterminate amount of securities is covered by this registration statement, the expenses in connection with the issuance and distribution of the securities are not currently determinable.

Item 15.    Indemnification of Directors and Officers

        Section 102 of the DGCL allows a corporation to eliminate the personal liability of a director to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except in cases where the director breached his or her duty of loyalty to the corporation or its stockholders, failed to act in good faith, engaged in intentional misconduct or a knowing violation of the law, willfully or negligently authorized the unlawful payment of a dividend or approved an unlawful stock redemption or repurchase or obtained an improper personal benefit. The registrant's certificate of incorporation contains a provision which eliminates directors' personal liability as set forth above.

        The registrant's certificate of incorporation and bylaws provide in effect that the registrant shall indemnify its directors and officers to the extent permitted by the DGCL. Section 145 of the DGCL provides that a Delaware corporation has the power to indemnify its directors, officers, employees and agents in certain circumstances. Subsection (a) of Section 145 of the DGCL empowers a corporation to indemnify any director, officer, employee or agent, or former director, officer, employee or agent, who was or is a party or is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the corporation), against expenses (including attorneys' fees), judgments, fines and amounts paid in settlement actually and reasonably incurred in connection with such action, suit or proceeding provided that such director, officer, employee or agent acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, provided that such director, officer, employee or agent had no reasonable cause to believe that his or her conduct was unlawful.

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        Subsection (b) of Section 145 of the DGCL empowers a corporation to indemnify any director, officer, employee or agent, or former director, officer, employee or agent, who was or is a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that such person acted in any of the capacities set forth above, against expenses (including attorneys' fees) actually and reasonably incurred in connection with the defense or settlement of such action or suit provided that such person acted in good faith and in a manner he or she reasonably believed to be in or not opposed to the best interests of the corporation, except that no indemnification may be made in respect of any claim, issue or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Court of Chancery shall determine that despite the adjudication of liability such person is fairly and reasonably entitled to indemnity for such expenses which the court shall deem proper.

        Section 145 further provides that to the extent that a director or officer or employee of a corporation has been successful in the defense of any action, suit or proceeding referred to in subsections (a) and (b) or in the defense of any claim, issue or matter therein, he or she shall be indemnified against expenses (including attorneys' fees) actually and reasonably incurred by him or her in connection therewith; that indemnification provided by Section 145 shall not be deemed exclusive of any other rights to which the party seeking indemnification may be entitled; and the corporation is empowered to purchase and maintain insurance on behalf of a director, officer, employee or agent of the corporation against any liability asserted against him or her or incurred by him or her in any such capacity or arising out of his or her status as such whether or not the corporation would have the power to indemnify him or her against such liabilities under Section 145; and that, unless indemnification is ordered by a court, the determination that indemnification under subsections (a) and (b) of Section 145 is proper because the director, officer, employee or agent has met the applicable standard of conduct under such subsections shall be made (1) by a majority vote of the directors who are not parties to such action, suit or proceeding, even though less than a quorum, (2) if there are no such directors, or if such directors so direct, by independent legal counsel in a written opinion, or (3) by the stockholders.

        The registrant has in effect insurance policies for general officers' and directors' liability insurance covering all of its officers and directors. In addition, the registrant has entered into indemnification agreements with its directors and officers. These indemnification agreements may require the registrant, among other things, to indemnify each such director or officer for certain expenses, including attorneys' fees, judgments, fines and settlement amounts incurred by such director or officer in any action or proceeding arising out of his or her service as one of the registrant's directors or officers.

Item 16.    Exhibits and Financial Statement Schedules

        See the Exhibit Index attached to this registration statement, which is incorporated by reference herein.

Item 17.    Undertakings

        (a)   The undersigned registrant hereby undertakes:

        (1)   To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

          (i)  To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

         (ii)  To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth

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in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20% change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement; and

        (iii)  To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;
provided, however, that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) above do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Securities and Exchange Commission by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

        (2)   That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

        (3)   To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

        (4)   That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser,

          (i)  Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

         (ii)  Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

        (5)   That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this

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registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

          (i)  Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

         (ii)  Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

        (iii)  The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

        (iv)  Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

        (b)   The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant's annual report pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of the securities at that time shall be deemed to be the initial bona fide offering thereof.

        (c)   Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

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INDEX TO EXHIBITS

Exhibit No.			Exhibit Description
	1.1	*	Form of Underwriting Agreement.
	3.1		Second Amended and Restated Certificate of Incorporation of the Company (incorporated by reference to Exhibit 3.1 to Amendment No. 5 to the Registrant's Registration Statement on Form S1 filed on May 16, 2016 (File No. 333205902)).
	3.2		Amended and Restated Bylaws of the Company (incorporated by reference to Exhibit 3.2 to Amendment No. 5 to the Registrant's Registration Statement on Form S1 filed on May 16, 2016 (File No. 333205902)).
	4.1		Specimen Common Stock Certificate of the Company (incorporated by reference to Exhibit 4.1 to Amendment No. 5 to the Registrant's Registration Statement on Form S1 filed on May 16, 2016 (File No. 333205902)).
	5.1	**	Opinion of Alston & Bird LLP.
	23.1	**	Consent of Ernst & Young LLP, independent registered public accounting firm.
	23.2	**	Consent of PricewaterhouseCoopers LLP, independent registered public accounting firm.
	23.3	**	Consent of Alston & Bird LLP (included in Exhibit 5.1).
	24.1	**	Power of Attorney (included on signature page to this registration statement).

*

To be filed by amendment or incorporated by reference in connection with any offering of common stock.

**

Filed herewith.

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SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Tucker, State of Georgia, on this 4^th day of September, 2019.

GMS INC.
By:	/s/ JOHN C. TURNER, JR. John C. Turner, Jr. President and Chief Executive Officer

POWER OF ATTORNEY

        KNOW ALL MEN BY THESE PRESENTS, that each of the undersigned directors and officers of GMS Inc. constitutes and appoints each of John C. Turner, Jr., Craig D. Apolinsky, and Lynn A. Ross, or either of them, each acting alone, his or her true and lawful attorney-in-fact and agent, with full powers of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any or all amendments (including post-effective amendments) to this registration statement and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, with full power of each to act alone, full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he or she might or could do in person, and hereby ratifying and confirming all that either of the said attorneys-in-fact and agents, or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

        Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed below by the following persons in the capacities and on the dates indicated.

Signature	Title	Date
/s/ JOHN C. TURNER, JR. John C. Turner, Jr.	President, Chief Executive Officer and Director (Principal Executive Officer)	September 4, 2019
/s/ LYNN A. ROSS Lynn A. Ross	Corporate Controller and Chief Accounting Officer (Interim Principal Financial Officer and Principal Accounting Officer)	September 4, 2019
/s/ RICHARD K. MUELLER Richard K. Mueller	Chairman of the Board	September 4, 2019
/s/ PETER C. BROWNING Peter C. Browning	Director	September 4, 2019
/s/ JOHN J. GAVIN John J. Gavin	Director	September 4, 2019
/s/ THERON I. GILLIAM Theron I. Gilliam	Director	September 4, 2019
/s/ BRIAN R. HOESTEREY Brian R. Hoesterey	Director	September 4, 2019
/s/ MITCHELL B. LEWIS Mitchell B. Lewis	Director	September 4, 2019

Signature	Title	Date
/s/ TERI P. MCCLURE Teri P. McClure	Director	September 4, 2019
/s/ RONALD R. ROSS Ronald R. Ross	Director	September 4, 2019
/s/ J. LOUIS SHARPE J. Louis Sharpe	Director	September 4, 2019
/s/ J. DAVID SMITH J. David Smith	Director	September 4, 2019