As filed with the Securities and Exchange Commission on January 4, 2017

Registration No. 333-208609

SECURITIES AND EXCHANGE COMMISSION

POST-EFFECTIVE AMENDMENT NO.1

TO

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

DIVIDEND REINVESTMENT AND

DIRECT STOCK PURCHASE PLAN

Sponsored by

Southwest Gas Holdings, Inc.

(Exact name of Registrant as specified in its charter)

5241 Spring Mountain Road

P.O. Box 98510

Las Vegas, Nevada 89193-8510

(702) 876-7237

(Address, including zip code, and telephone number, including area code, of Registrant’s principal executive offices)

KAREN S. HALLER

Senior Vice President/General Counsel and Corporate Secretary

Southwest Gas Holdings, Inc.

5241 Spring Mountain Road

P.O. Box 98510

Las Vegas, Nevada 89193-8510

(702) 876-7237

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Approximate date of commencement of proposed sale to the public: From time to time 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.  ☐

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.  ☒

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.  ☐

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.  ☒

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.  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act (check one):

EXPLANATORY NOTE

This Post-Effective Amendment No. 1 to Registration Statement on Form S-3, File No. 333-208609 (the “Registration Statement”), is being filed by Southwest Gas Holdings, Inc. (the “Company” or the “Registrant”) pursuant to Rule 414 under the Securities Act of 1933, as amended (the “Securities Act”), to reflect the holding company reorganization (the “Reorganization”) of Southwest Gas Corporation (the “Predecessor Company”). The Reorganization was completed on January 1, 2017 and was effected pursuant to the Agreement and Plan of Merger, dated as of December 28, 2016, by and among the Company, the Predecessor Company and Southwest Reorganization Co. (“MergerSub”) and the Plan of Reorganization dated as of December 28, 2016, by and among the Company, the Predecessor Company, Merger Sub and Southwest Gas Utility Group, Inc. in accordance with the California Corporations Code. As a result of the Reorganization, Predecessor Company became a wholly owned subsidiary of the Company, and the Company became the successor issuer to Predecessor Company pursuant to Rule 12g-3 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”).

In the Reorganization, each share of the issued and outstanding common stock of Predecessor Company was converted automatically into one share of common stock of the Company. In connection with the Reorganization, the Company assumed the Predecessor Company’s Dividend Reinvestment and Direct Stock Purchase Plan. All of the common stock issuable under the Dividend Reinvestment and Direct Stock Purchase Plan is issuable upon the same terms and conditions as were in effect immediately prior to the completion of the Reorganization, except that all such common stock shall be common stock of the Company.

The Registrant is filing the Registration Statement pursuant to Rule 414 solely to update the Registration Statement as a result of the Reorganization. In accordance with Rule 414(d) under the Securities Act, except as modified by this Post-Effective Amendment No. 1, the Registrant, now as successor issuer to Predecessor Company pursuant to Rule 12g-3 of the Exchange Act, hereby expressly adopts the Registration Statement as its own registration statement for all purposes of the Securities Act and the Exchange Act, as updated by subsequent filings under the Exchange Act.

PART II

INFORMATION NOT REQUIRED IN THE PROSPECTUS

The information set forth in this item is incorporated by reference from Item 14 of the registration statement on Form S-3, File No. 333-208609, effective as of December 18, 2015.

The Company’s Articles of Incorporation contain a provision which eliminates the liability of directors for monetary damages to the fullest extent permissible under California law. The General Corporation Law of California (the “Law”) (i) authorizes the elimination of liability of directors for monetary damages in an action brought by a shareholder in the right of the Company or by the Company for breach of a director’s duties to the Company and its shareholders and (ii) authorizes the Company to indemnify directors and officers for monetary damages for all acts or omissions committed by them in their respective capacities; provided, however, that liability is not limited nor may indemnification be provided (a) for acts or omissions that involve intentional misconduct or knowing and culpable violation of law, (b) for acts or omissions that a director or officer believes to be contrary to the best interests of the Company or its shareholders or that involve the absence of good faith on the part of a director or officer seeking indemnification, (c) for any transaction from which a director or officer derives an improper personal benefit, (d) for acts or omissions that show a reckless disregard for the director’s or officer’s duty to the Company or its shareholders in circumstances in which such person was aware, or should have been aware, in the ordinary course of performing his or her duties, of a risk of serious injury to the Company or its shareholders, (e) for acts or omissions that constitute an unexcused pattern of inattention that amounts to an abdication of the director’s or officer’s duty to the Company or its shareholders, and (f) for liabilities arising under Section 310 (contracts in which a director has a material financial interest) and Section 316 (certain unlawful dividends, distributions, loans and guarantees) of the Law. In addition, the Company may not indemnify directors and officers in circumstances in which indemnification is expressly prohibited by Section 317 of the Law.

The Bylaws of the Company provide that the Company has the power to indemnify directors and officers to the fullest extent permitted under California law and the Company’s Articles of Incorporation. The Company has entered into indemnification agreements with its directors and officers which require that the Company indemnify such directors and officers in all cases to the fullest extent permitted by applicable provisions of the Law. The Company also maintains a directors’ and officers’ liability insurance policy insuring directors and officers of the Company for covered losses as defined in the policy.

The undersigned Registrant hereby undertakes:

To file, during any period in which offers or sales are being made, a post-effective amendment to this Registration Statement:

provided, however, that paragraphs (i), (ii) and (iii) 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 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 this Registration Statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of this Registration Statement.

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.

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.

That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

That, for the purpose of determining liability of a 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 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:

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 this Registration Statement 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.

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.

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 Las Vegas, State of Nevada, on January 4, 2017.

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 date indicated.