SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Filed by the Registrant  x                             Filed by a Party other than the Registrant  ¨

Check the appropriate box:

    Southwest Gas Corporation    

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

		Notice of 20142015 Annual Meeting of Shareholders and Proxy Statement
		Annual Meeting 20142015   May 8, 20147, 2015 – Las Vegas, Nevada

SOUTHWEST GAS CORPORATION

5241 Spring Mountain Road

Las Vegas, Nevada 89150

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS

To be Held Thursday, May 8, 20147, 2015

NOTICE IS HEREBY GIVEN that the Annual Meeting of Shareholders of Southwest Gas Corporation (the “Company”) will be held on Thursday, May 8, 2014,7, 2015, at 10:00 a.m. PDT, at Cili Restaurant at Bali Hai Golf Club, 5160 Las Vegas Blvd. South, Las Vegas, Nevada 89119, for the following purposes:

The Board of Directors of the Company established March 11, 2014,10, 2015, as the record date for the determination of shareholders entitled to vote at the Annual Meeting and to receive notice thereof.

Shareholders are cordially invited to attend the Annual Meeting in person. WHETHER OR NOT YOU EXPECT TO ATTEND THE MEETING, PLEASE VOTE THE ACCOMPANYING PROXY BY TELEPHONE, INTERNET OR MAIL AT YOUR EARLIEST CONVENIENCE. IF YOU MAIL IN YOUR PROXY, PLEASE USE THE ENCLOSED POSTAGE-PAID ENVELOPE ACCOMPANYING YOUR PROXY CARD.

The Securities and Exchange Commission rules allow the Company to furnish its proxy materials via the internet. This process reduces the costs of printing and distributing our proxy materials. Therefore, we are mailing to most of our shareholders a Notice of Internet Availability of Proxy Materials instead of a paper copy of this Proxy Statement and our 20132014 Annual Report to Shareholders. The Notice contains instructions on how to access those documents via the internet. The Notice also contains instructions on how to request a paper or e-mail copy of our proxy materials, including this Proxy Statement, our Annual Report to Shareholders and a Proxy Card. All shareholders who do not receive a Notice of Internet Availability of Proxy Materials will receive a paper copy of the proxy materials by mail.

The Annual Report to Shareholders for the year ended December 31, 2013,2014, is either enclosed or available athttp://www.swgas.com/proxymaterials.

Karen S. Haller

Senior Vice President/General Counsel and Corporate Secretary

March 26, 201427, 2015

NOTICE OF INTERNET AVAILABILITY OF PROXY MATERIALS

SOUTHWEST GAS CORPORATION

5241 Spring Mountain Road

Las Vegas, Nevada 89150

Important Notice Regarding the Availability of Proxy Materials for the

Shareholder Meeting to Be Held on May 8, 20147, 2015

The Proxy Statement and Annual Report to Shareholders are available at

http://www.swgas.com/proxymaterials

The Annual Meeting of Shareholders of Southwest Gas Corporation (the “Company”) will be held on Thursday, May 8, 2014,7, 2015, at 10:00 a.m. PDT, at Cili Restaurant at Bali Hai Golf Club, 5160 Las Vegas Blvd. South, Las Vegas, Nevada 89119.

At the meeting you will be asked to elect 12 directors, to approve, on an advisory basis, the Company’s executive compensation, to reapprove and amend the Company’s Management Incentive Plan, to ratify the selection of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 20142015 and to transact such other business as may properly come before the meeting or any adjournment thereof. The Company’s Board of Directors is asking for your support of the director nominees, the advisory approval of executive compensation the reapproval and amendment of the Management Incentive Plan and the selection of PricewaterhouseCoopers LLP.

The following materials are available at the web address provided above.

Directions to attend the Annual Meeting and vote in person are included on the map on page M-1 of the Notice of 20142015 Annual Meeting of Shareholders and Proxy Statement.

TABLE OF CONTENTS

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Jeffrey W. Shaw,John P. Hester, President and Chief Executive Officer

March 26, 201427, 2015

Dear Shareholders:

You are cordially invited to the Annual Meeting of Shareholders of Southwest Gas Corporation (the “Company”) scheduled to be held on Thursday, May 8, 2014,7, 2015, at Cili Restaurant at Bali Hai Golf Club, 5160 Las Vegas Blvd. South, Las Vegas, Nevada 89119, commencing at 10:00 a.m. PDT. Your Board of Directors looks forward to greeting personally those shareholders able to attend.

At the meeting you will be asked to elect 12 directors, to approve, on a non-binding advisory basis, the Company’s executive compensation, to reapprove and amend the Company’s Management Incentive Plan, to ratify the selection of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 2014,2015 and to transact such other business as may properly come before the meeting or any adjournment thereof. Your Board of Directors asks you to support the director nominees, cast an affirmative vote to approve executive compensation reapprove and amend the Management Incentive Plan and ratify the selection of PricewaterhouseCoopers LLP.

It is important that your shares are represented and voted at the meeting regardless of the number of shares you own and whether or not you plan to attend. Accordingly, we request you vote the accompanying proxy by telephone, internet or mail at your earliest convenience.

Your interest and participation in the affairs of the Company are greatly appreciated.

Sincerely,

M-1

SOUTHWEST GAS CORPORATION

5241 Spring Mountain Road • P.O. Box 98510

· Las Vegas, Nevada 89193-8510·

PROXY STATEMENT

March 26, 201427, 2015

GENERAL INFORMATION

We are providing these proxy materials to you in connection with the solicitation of proxies by the Board of Directors (the “Board”) of Southwest Gas Corporation (the “Company”) for the 20142015 Annual Meeting of Shareholders and for any adjournment or postponement of the Annual Meeting.

We intend to mail a Notice of Internet Availability and make this Proxy Statement and a Proxy Card available to shareholders on our website athttp://www.swgas.com/proxymaterials on or about March 26, 2014.27, 2015. We also will be mailing the materials to certain shareholders on or about March 26, 2014,27, 2015, and to those shareholders who request paper or e-mail copies of the proxy materials.

What is the purpose of the Annual Meeting?

At the Annual Meeting, shareholders will act upon the matters outlined in the notice of meeting and described in these materials, including the election of directors, the advisory approval of executive compensation, the reapproval and amendment of the Management Incentive Plan, the ratification of the selection of our independent registered public accounting firm and the transaction of other business, if properly presented at the meeting.

Who is entitled to vote at the Annual Meeting?

Only shareholders of record at the close of business on March 11, 2014,10, 2015, the record date for the Annual Meeting, are entitled to receive notice of and vote at the meeting. If you were a shareholder of record on that date, you are entitled to vote all of the shares that you held on that date at the meeting, or any adjournment or postponement of the meeting.

If your shares are registered directly in your name, you are the holder of record of those shares. As the holder of record, you are receiving these proxy materials directly from us and have the right to vote by mailing your Proxy Card directly to us, submitting your voting instructions via the Internet or by telephone or voting in person at the Annual Meeting. If you wish to vote in person at the Annual Meeting, you must provide proof of identification, e.g., driver���sdriver’s license, state picture identification or passport.

If you hold your shares in a brokerage account or through a bank or other holder of record, you are the beneficial owner of the shares, and the shares are held in “street name.” Your broker, bank or other holder of record (collectively referred to as “broker”) is sending these proxy materials to you. As the beneficial owner, you have the right to direct your broker how to vote by following the instructions that accompany these proxy materials or to vote in person at the Annual Meeting. If you wish to vote in person at the Annual Meeting, you must provide proof of identification, e.g., driver’s license, state picture identification or passport, and proof that you were the owner of the shares on March 11, 2014,10, 2015, e.g., original brokerage statement.

If you hold your shares indirectly in the Southwest Gas Corporation Employees’ Investment Plan (the “EIP”), you have the right to direct the EIP trustee how to vote your shares by following the instructions from the EIP trustee accompanying the Proxy Statement. If you do not direct the EIP trustee how to vote your shares, then the EIP trustee will vote your shares in the same proportion as the shares for which timely instructions were received from other EIP participants.

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How many votes do I have?

You have one vote for each share of the Company’s common stock (“Common Stock”) you owned as of the record date for the Annual Meeting.

How do I vote?

If you are a registered shareholder, you can vote either in person at the Annual Meeting or by proxy whether or not you attend the meeting. To vote by proxy, you must either:

If your shares are held in street name, you should follow the voting instructions provided by your bank or broker.

Can I revoke or change my vote?

Yes, you can revoke or change your vote at any time prior to the voting of your shares at the Annual Meeting by (a) casting a new vote by telephone or over the internet; (b) sending a new Proxy Card with a later date; (c) sending a written notice of revocation that is received on or prior to May 7, 20146, 2015, by mail to Wells Fargo Shareowner Services, Southwest Gas Corporation, P.O. Box 64873, Saint Paul, MN 55164-9397, or by facsimile at 651-450-4026; or (d) voting by ballot at the Annual Meeting.

What are the Board’s recommendations?

The Board’s recommendations are set forth with the description of each proposal in this Proxy Statement. In summary, the Board recommends a vote:

With respect to any other matter that properly comes before the Annual Meeting, LeRoy C. Hanneman, Jr. and Michael J. Melarkey, the proxies designated by the Board and identified in the accompanying Proxy Card, will vote all proxies granted to them at their discretion.

How many votes must be present to hold the Annual Meeting?

We will have a quorum, and will be able to conduct the business of the Annual Meeting, if the holders of a majority of the shares entitled to vote are represented in person or by proxy at the meeting. As of the record date, 46,492,91046,639,027 shares of Common Stock were outstanding and the

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presence, in person or by proxy, of the holders of at least 23,246,45623,319,514 shares of Common Stock will be required to establish a quorum. Proxies received but marked as abstentions and broker non-votes will be included in the calculation of the votes considered being present at the meeting.

A “broker non-vote” occurs when a broker lacks discretionary voting power to vote on a “non-routine” proposal and a beneficial owner fails to give the broker voting instructions on that matter. The rules of the New York Stock Exchange (the “NYSE”) determine whether matters presented at the Annual Meeting are “routine” or “non-routine” in nature. The election of directors is not considered a “routine” matter. Similarly, the advisory vote to approve executive compensation and the vote on reapproval and amendment of the Management Incentive Plan areis not considered a “routine” matters.matter. Therefore, beneficial owners that hold in “street name” will have to give voting instructions to their brokers in order for a broker to vote on the election of directors and the advisory vote to approve executive compensation and the reapproval and amendment of the Management Incentive Plan.compensation. The ratification of the selection of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 20142015 is considered a “routine” matter, and brokers have the discretionary voting power to vote on this matter without any instructions from the beneficial owners.

What vote is required to approve each Proposal?

Directors are elected by a plurality of the votes cast. The affirmative vote of a majority of shares of Common Stock represented and voting at a duly held Annual Meeting at which a quorum is present (which shares of Common Stock voting affirmatively also constitute at least a majority of the required quorum) is necessary to reapprove and amend the Management Incentive Plan, to ratify PricewaterhouseCoopers LLP’s selection as the independent registered public accounting firm for the Company for fiscal year 20142015 and to approve, on an advisory basis, the Company’s executive compensation. Although the result of the vote to approve executive compensation is non-binding, the Board will consider the outcome of the vote when making future executive compensation decisions.

Do I have an opportunity to cumulate my votes for director nominees?

Shareholders have cumulative voting rights for the election of directors if certain conditions are met. Shareholders entitled to vote may cumulate their votes for a candidate or candidates placed in nomination at the meeting if, prior to the voting at the meeting, notice has been given that a shareholder intends to cumulate his or her votes. A shareholder deciding to cumulate his or her votes may cast as many votes as there are directors to be elected, multiplied by the number of shares of Common Stock held by such shareholder on the record date. The votes may be cast for one candidate or allocated among two or more candidates in any manner the shareholders choose. If any shareholder has given notice of cumulative voting, all shareholders may cumulate their votes for candidates in nomination. Note, however, that cumulative voting will have no impact on the result of the election of directors at the Annual Meeting because there is only one nominee for each of the 12 seats on the Board.

If our proxies determine that a sufficient number of shareholders exercise cumulative voting rights to elect one or more candidates, our proxies will:

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How are my votes counted?

We will appoint either one or three inspectors of election in advance of the meeting to tabulate votes, to ascertain whether a quorum is present and to determine the voting results on all matters presented to Company shareholders.

What if I do not vote for any or all of the matters listed on my Proxy Card?

If you return a signed Proxy Card without indicating your vote on any or all of the matters to be considered at the Annual Meeting, your shares will be voted “FOR” the director nominees listed on the Proxy Card, “FOR” the advisory vote to approve executive compensation, “FOR” the reapproval and amendment of the Management Incentive Plan and “FOR” the ratification of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 2014.2015. If you hold your shares in “street name” and do not provide instructions to your broker, your shares will not be voted in the election of directors or in the advisory vote to approve executive compensation or with respect to the Management Incentive Plan and will be voted inat your broker’s discretion on the ratification of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 2014.2015.

Are proxy materials available on the Internet?

The Notice of 20142015 Annual Meeting of Shareholders and Proxy Statement and the 20132014 Annual Report to Shareholders are available athttp://www.swgas.com/proxymaterials.

Why did I receive a Notice of Internet Availability of Proxy Materials instead of a full set of the proxy materials?

The Securities and Exchange Commission (“SEC”) rules allow us to furnish our proxy materials via the internet. Accordingly, we sent to the majority of our shareholders a Notice of Internet Availability of

Proxy Materials for this year’s Annual Meeting of Shareholders. Instructions on how to access the proxy materials via the internet or to request a paper or e-mail copy can be found in the Notice of Internet Availability of Proxy Materials athttp://www.swgas.com/proxymaterials. In addition, shareholders may request to receive proxy materials in printed form by mail or e-mail on an ongoing basis by submitting a request to us at eitherwww.investorelections.com/swx orhttp://www.swgas.com/proxymaterials. A shareholder’s election to receive proxy materials by mail or e-mail will remain in effect until the shareholder terminates it.

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Why didn’t I receive a Notice of Internet Availability of Proxy Materials?

We are providing certain shareholders, including shareholders who have requested to receive paper copies of proxy materials, with paper copies of the proxy materials instead of, or in addition to, a Notice of Internet Availability of Proxy Materials.

Can I vote my shares by completing and returning the Notice of Internet Availability of Proxy Materials?

No. The Notice of Internet Availability of Proxy Materials does, however, provide instructions on how to vote your shares.

Can the shares that I hold in a brokerage account or the EIP be voted if I do not instruct my broker or the EIP trustee?

Could other matters be decided at the Annual Meeting?

We do not know of any other matters that will be considered at the Annual Meeting. However, if you give your proxy and other matters are properly brought before the meeting, your shares will be voted at the discretion of the proxies, unless otherwise instructed.

What Rules of Conduct will govern the Annual Meeting?

To ensure that our Annual Meeting is conducted in an orderly fashion and the shareholders wishing to speak at the meeting have a fair opportunity to do so, we will have certain guidelines and rules for the conduct of the meeting, which we will provide to those attending the meeting.

What happens if the Annual Meeting is postponed or adjourned?

If the Annual Meeting is postponed or adjourned, your proxy will still be good and may be voted at the postponed or adjourned meeting. You will still be able to change or revoke your proxy until it is voted.

Who is soliciting my proxy?

Your proxy is being solicited by the Board, and the Company will bear the entire cost of the proxy solicitation. Morrow & Co., LLC (“Morrow”), 470 West Avenue, Stamford, CT 06902 has been employed to assist in obtaining proxies from certain shareholders at an estimated cost of $8,500, plus

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certain expenses. Arrangements have also been made with brokerage houses and other custodians, nominees and fiduciaries to send proxies and proxy materials to you, if your shares are held in “street name.” Morrow will reimburse them for their expenses in providing the materials to you. In addition, solicitation by our directors, officers or employees in person or by telephone, e-mail or facsimile may supplement solicitation of proxies. No additional compensation will be paid for such services.

GOVERNANCE OF THE COMPANY

Board of Directors

Under the provisions of the California Corporations Code and the Company’s Bylaws, the Company’s business, property and affairs are managed by or under the direction of the Board. The Board is kept informed of the Company’s business through discussions with the Chief Executive Officer and other officers, by reviewing materials provided by management and by participating in Board and committee meetings.

Independence

The Board has determined that directors Boughner, Cárdenas, Chestnut, Comer, Hanneman, Maffie, Mariucci, Melarkey, Thoman, Thomas and Wright have no material relationships with the Company and are independent (“Independent Directors”). The Board has also determined that all of the members of the Audit, Compensation and Nominating and Corporate Governance Committees are independent.

In making these determinations, the Board reviewed all transactions or relationships with the Company using a definition of “material relationships” that (i) includes the criteria listed in Section 303A of the listing requirements of the NYSE and (ii) presumes that matters not subject to disclosure pursuant to Item 404 of Regulation S-K of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and matters above the Item 404 threshold which are authorized by the Company’s regulatory tariffs, are not “material relationships.” The definition of “material relationships” for directors on the Audit Committee also includes the criteria listed in Section 10A(m)(3) of the Exchange Act. The definition of “material relationships” for directors serving on the Compensation Committee also includes the criteria listed in Section 16(b) of the Exchange Act and Section 162(m) of the Internal Revenue Code (the “Code”). The independence criteria used are included in the Company’s Corporate Governance Guidelines, which are available on the Company’s website at:http://www.swgas.com.

The Board based its independence determination primarily on a review of the responses of the directors and officers to questions regarding employment and compensation history, affiliations and family relationships and on discussions with directors. In concluding that the directors listed above are independent, the Board reviewed transactions involving director Thomas and reviewed director Maffie’s status as a retired executive officer of the Company.

approximately $7,500. The total lease payments over the life of the lease will be approximately $450,000, plus a pro-rata share of operating and other expenses. This lease transaction terminates in May 2014. In 2011, we began purchasing communications-related products and services from Switch Communications Group, LLC (“SCG”) and its majority-owned subsidiary, Switch Business Solutions, LLC (“SBS” and, together with SCG, “Switch”). The contract with Switch, a company in which Mr. Thomas also has an interest, has an annual cost estimated to be approximately $525,000 in 2014.2015. The Nominating and Corporate Governance Committee has determined that neither the lease nor the Switch transaction is not material and that Mr. Thomas’ ownership interests in the leasing entity and Switch would not result in a material relationship between Mr. Thomas and the Company. However, because of such interests, Mr. Thomas does not satisfy the criteria to serve on the Compensation Committee or to vote as a director on matters involving awarding equity-based compensation under the provisions of Section 16(b) of the Exchange Act or

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Board Meetings

Regular Board meetings for 20142015 are scheduled for the fifth Fridayfourth Monday of January, the fourth WednesdayTuesday of February, the firstfifth Friday of August,July, the thirdfifth Tuesday of September, the second Friday of November and the Wednesday before the Annual Meeting of Shareholders in May. Additional meetings are called on an as-needed basis and the Board sometimes acts by written consent without a meeting. An organizational meeting is also held immediately following the Annual Meeting of Shareholders. The Board held six regular meetings, one special meeting and one organizational meeting in 2013.2014. Each incumbent director attended more than 75% of the Board and committee meetings on which he or she served during 2013.2014. Non-management directors are expected to meet in an executive session at least four times a year, and the Independent Directors are expected to meet at least once a year. These sessions are presided over by Michael J. Melarkey, Chairman of the Board (the “Chair”), who is the current “Presiding Director.”

Board Leadership Structure

The policy of the Board is that the role of Chair should be separate from that of the Chief Executive Officer (“CEO”). The Chair is elected annually, at the organizational meeting, by the full Board. Every three years or upon a Chair’s resignation, retirement, or failure to be re-elected to the Board by shareholders, the Board does an in-depth assessment of potential candidates for that position. The Board believes that this leadership structure is the appropriate structure for the Company sincebecause it allows the Board to exercise true independent oversight of management. It is the Board’s intention to reelect Mr. Melarkey as Chair, subject to his reelection as a director at the Annual Meeting of Shareholders.

Risk Oversight

The entire Board is responsible for reviewing and overseeing the Company’s internal risk management processes and policies to help ensure that the Company’s corporate strategy is functioning as directed and that necessary steps are taken to foster a culture of risk-aware and risk-adjusted decision making throughout the Company.

Regulation by various state and federal utility regulatory commissions is one of the key risks that is accepted as a part of being a public utility. The limits imposed on the Company as a public utility permeate its business operating model (including the pricing of services, the authorized areas of service and the obligations to serve the public). Other risks are associated with credit, liquidity and operational matters and have evolved with changes in the natural gas industry.

The nature of these risks and the continuing obligations imposed on the Company, as a public utility, resulted in the integration of risk assessment in the normal business oversight process. The Board receives regular reports from management in areas of material risk to the Company, including credit risk, liquidity risk and operational risk. Credit and liquidity risks are addressed in the review of capital budgets and ongoing capital requirements. Liquidity risks are also addressed in the review of

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gas supply acquisition and related regulatory cost recovery. Operational risks are addressed in the review of operating budgets and related regulatory compliance requirements, including pipeline safety requirements. The full Board receives these reports from management to help enable it to oversee and manage the Company’s risks in these areas. This oversight responsibility rests with the full Board and is not assigned to any of the permanent committees.

Committees of the Board

The permanent Board committees are the Audit Committee, Compensation Committee, Nominating and Corporate Governance Committee and Pension Plan Investment Committees.Committee. Each committee has established responsibilities, and the Audit, Compensation and Nominating and Corporate Governance Committees have detailed charters designed to satisfy applicable legal and regulatory requirements. The Audit, Compensation and Nominating and Corporate Governance Committees are composed solely of independent directors as outlined above. We refer to the committees of the Board by the name of the specific committee or, where it is clear by the context of the discussion, simply as the “committee.”

TheAudit Committee, whose functions are discussed here and below under the caption “Audit Committee Information,” is a separately designated standing committee established in accordance with Section 3(a)(58)(A) of the Exchange Act. It consists of directors Comer (Chair), Boughner, Chestnut, Hanneman, Thoman and Thomas. The committee meets periodically with management to consider, among other things, the adequacy of the Company’s internal controls and financial reporting process. The committee also discusses these matters with the Company’s independent registered public accounting firm, internal auditors and Company financial personnel. The Board has determined that directors Comer and Thoman each qualify as an “audit committee financial expert,” as the term is defined in Item 407(d)(5)(ii) of Regulation S-K under the Exchange Act.

TheCompensation Committee is responsible for determining CEO compensation and making recommendations to the Board annually on such matters as directors’ fees and benefit programs, executive compensation and benefits and compensation and benefits for all other Company employees. The committee’s responsibilities, as outlined in its charter, cannot be delegated without Board approval. The committee receives recommendations from management on the amount and form of executive and director compensation; however, the committee has the ability to directly employ consultants to assess the executive compensation program. The committee is also responsible for the “Compensation Committee Report” and related disclosures contained in this Proxy Statement. The committee consists of directors Boughner (Chair), Cárdenas,Comer, Melarkey, Thoman and Wright.

TheNominating and Corporate Governance Committee is responsible for making recommendations to the Board regarding nominees to be proposed for election as directors; evaluating the Board’s size, composition, organization, processes, practices and number of committees; and developing the criteria for the selection of directors. The committee considers written suggestions from shareholders regarding potential nominees for election as directors. The process for selecting directors

is addressed in more detail below under the caption “Selection of Directors.” The committee is also charged with the responsibility of developing and recommending to the Board corporate governance principles and compliance programs for the Company. The committee consists of directors Hanneman (Chair), Cárdenas, Mariucci, Melarkey, Thomas and Wright.

ThePension Plan Investment Committeeestablishes, monitors and oversees, on a continual basis, asset investment policy and practices for the Company’s defined benefit retirement plan. The committee consists of directors Mariucci (Chair), Cárdenas, Chestnut Comer and Maffie.

During 2013,2014, the Audit Committee held six meetings, the Compensation Committee held fourfive meetings, the Nominating and Corporate Governance Committee held three meetings and the Pension Plan Investment Committee held fourthree meetings.

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The charters for the Audit, Compensation and Nominating and Corporate Governance Committees, the Company’s Corporate Governance Guidelines and the Company’s code of business conduct that applies to all employees, officers and directors are available on the Company’s website at:http://www.swgas.com. Print versions of these documents are available to shareholders upon request directed to the Corporate Secretary, Southwest Gas Corporation, 5241 Spring Mountain Road, Las Vegas, NV 89150.

Selection of Directors

We believe the Board should be composed of individuals with varied, complementary backgrounds, who possess certain core competencies, some of which may include broad experience in business, finance or administration, and familiarity with national and international business matters and the energy industry. Additional factors that will be considered in the selection process include the following:

We define “diversity” in a broad sense, i.e., race, color, gender, national origin, religion and disability. Neither the Nominating and Corporate Governance Committee nor the Board has a policy with regard to the consideration of diversity in identifying director nominees. However, the Nominating and Corporate Governance Committee takes diversity into consideration as it does the other factors listed above in selecting the director nominees for approval by the Board. The Nominating and Corporate Governance Committee does not assign a specific weight to any one factor.

The Nominating and Corporate Governance Committee will consider director candidates suggested by shareholders by applying the criteria for candidates described above and considering the additional information referred to below. Shareholders who would like to suggest a candidate should write to the Company’s Corporate Secretary and include:

*

The name of and contact information for the candidate;

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When seeking a candidate for director, the Nominating and Corporate Governance Committee may solicit suggestions from incumbent directors, management or others. The committee may also retain a search firm to identify potential candidates.

The Nominating and Corporate Governance Committee has an ongoing program of identifying potential director candidates throughout the Company’s service territories. As candidates are identified, their qualifications are reviewed in light of the selection criteria, as outlined above. Whether any of such candidates are selected depends upon the current director composition, the dynamics of the Board and the ongoing requirements of the Company.

Shareholders may also nominate a person for election to the Board at an annual meeting by giving written notice to the Company not less than 120 days prior to the first anniversary of the date of the proxy statement for the preceding year’s annual meeting, or within 10 days after notice is mailed or public disclosure is made regarding either a change of the annual meeting by more than 30 days or a special meeting at which directors are to be elected. In order to make such a nomination, a shareholder is required to include in the written notice the following:

Shareholder Nominees

There have been no director nominees submitted by shareholders for consideration for election at this year’s Annual Meeting of Shareholders, and the deadline for submissions has passed.

Transactions with Related Persons

The Company has written policies and procedures for the review, approval and ratification of transactions with related persons. The policy addresses transactions in which the Company was or is a participant, the amount exceeds $120,000 and a related person had or will have a direct or indirect material interest. The definition of “related person” includes any director, officer, nominee for director or five percent beneficial owner and any of their immediate family members. These transactions will be reported to the Company’s General Counsel, reviewed by the Nominating and Corporate Governance Committee and approved or ratified only if the committee determines that the transaction is not inconsistent with the best interests of the Company. The policy, included in the Company’s Corporate Governance Guidelines, is available on the Company’s website at:http://www.swgas.com.

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Each transaction with a related person is unique and must be assessed on a case-by-case basis. In determining whether or not a transaction is inconsistent with the best interests of the Company, the Nominating and Corporate Governance Committee considers all of the relevant facts and circumstances available to the committee, including without limitation:

The Company was engaged in threetwo transactions with related persons during 2013.2014. One involves a commercial lease for a Company payment center with an entity in which Mr. Thomas has an interest. The second involves the purchase of communications-related products and services from Switch, a company in which Mr. Thomas has an interest. The thirdother involves a consulting agreement with an entity owned by Dr. Joseph W. Haller, the spouse of Karen S. Haller, the Company’s General Counsel and Corporate Secretary.

The lease of commercial property for a Company payment center is for five years and began in 2009 at an initial monthly rental rate of approximately $6,500. There are approximately 2 months left on the lease term, and the Company has decided not to renew the lease. The current monthly rental rate is approximately $7,500 following the application of the annual minimum rent increase, and the total lease payments over the life of the lease will be approximately $450,000, plus a pro rata share of

operating and other expenses. Mr. Thomas and his siblings have a 20% interest in the entity that is leasing the commercial property to the Company, through their ownership in Thomas & Mack Co., LLC. The amount of property subject to the lease and annual revenues flowing through to Thomas & Mack Co., LLC, is insignificant in relation to its commercial property holdings and associated annual revenues. The Nominating and Corporate Governance Committee determined that the lease transaction was not material.

The Company purchases, in arm’s length negotiated, ordinary course commercial transactions, communications-related products and services from Switch pursuant to an agreement that became effective in 2011. Mr. Thomas owns, either directly or indirectly, an approximate 6.6% equity interest as a passive investor in SCG. Mr. Thomas’ family members own collectively, either directly or indirectly, approximately 16.25% of the equity interests of SCG. Mr. Thomas does not actively engage in the management of SCG or SBS. Mr. Thomas’ sibling, who is affiliated with SCG, is not involved in the daily business operations or decisions of SCG and does not perform any policy-making functions for SCG. Additionally, Mr. Thomas’ sibling is not and never has been an employee of SCG and none of the employees or contractors of SCG report to him. We expect to pay Switch approximately $525,000 in 2014,2015, with incremental annual increases thereafter. The transaction with Switch is expected to represent less than 1% of Switch’s consolidated revenue in each year over the life of the agreement. The Nominating and Corporate Governance Committee determined that this transaction was not material.

The agreement the Company entered into with Dr. Haller in 2008 was designed to secure computer application development/support for the Company’s transmission pipeline integrity management program and engineering data analysis services. The agreement has been extended multiple times, including in November 20122013 for calendar year 2013,2014, at an actual cost of $155,000,$155,835, and

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in December 20132014 for the calendar year 2014,2015, at an expected cost of $175,000. The Nominating and Corporate Governance Committee determined that Ms. Haller has a direct material interest in the transaction; however, consistent with the Company’s related person transaction policy, the committee determined that entering into and continuing the agreement is not inconsistent with the best interests of the Company. Given the valuable skill set that Dr. Haller possesses, the Company anticipates that the agreement may continue to be extended periodically.

Directors and Officers Share Ownership Guidelines

In order to better align the interests of management and the Board with that of all shareholders, the Company has adopted Common Stock ownership guidelines for directors and officers.

Each outside director is required to retain at least five times the value of his or her annual cash retainer in Company Common Stock (or equivalents), and a portion of this ownership requirement equal to at least two times the annual cash retainer must be Company Common Stock purchased by the outside director. Each outside director is required to fulfill the purchase requirement within two years of beginning service on the Board. All equity compensation received by each outside director must be held until end of service on the Board. All outside directors are currently in compliance with these guidelines.

Each Company officer is required to accumulate Company Common Stock with a target value equal to a multiple of the officer’s base salary, ranging from one times base salary for vice presidents, three times base salary at the senior vice president level and above and five times base salary for the Chief Executive Officer. If an officer has not yet reached the applicable target ownership requirement, he or she is required to retain a portion of the shares of Company Common Stock acquired from any stock option exercise or the vesting of restricted stock units or performance shares. The applicable retention rate is 75% for the Chief Executive Officer and 50% for all other officers. Qualified shares

include Common Stock owned directly by the officer or his or her spouse, Company Common Stock held by the officer or his or her spouse in the Company’s 401(k) or Dividend Reinvestment Plan and performance-based restricted stock units and performance shares which have been granted but are subject to time vesting requirements. All officers are currently in compliance with these guidelines.

Compensation Committee Interlocks and Insider Participation

Board members who served on the Compensation Committee during 20132014 were directors Boughner, Cárdenas, Comer, Melarkey, Thoman and Wright. None of the members has ever been an officer or employee of the Company or any of its subsidiaries, and no “compensation committee interlocks” existed during 2013.2014. No member of the Compensation Committee had any relationship requiring disclosure under any paragraph of Item 404 of Regulation S-K of the Exchange Act.

Director Attendance at Annual Meetings

We normally schedule Board meetings in conjunction with each Annual Meeting of Shareholders and each director nominee is expected to attend the Board meetings and the Annual Meeting of Shareholders. Last year, all of the directors attended the 20132014 Annual Meeting of Shareholders.

Communications with Directors

Any shareholder and other interested parties who would like to communicate with the Board, the Presiding Director or any individual director can write to:

Southwest Gas Corporation

Corporate Secretary

5241 Spring Mountain Road

P.O. Box 98510

Las Vegas, NV 89193-8510

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Depending on the subject matter, the Corporate Secretary will either:

If the communication is addressed to the Presiding Director, the communication will be forwarded directly to the Presiding Director and will not be processed by the Corporate Secretary. At each regular Board meeting, management presents a summary of all communications received since the last Board meeting which were not previously forwarded and such communications are made available to all of the directors.

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ELECTION OF DIRECTORS

(Proposal 1 on the Proxy Card)

The Board of Directors Recommends a Vote FOR Election of the Director Nominees.

Names, Qualifications and Reasons for Selection of Nominees

Each director elected at an annual meeting will serve until the next annual meeting and until his or her successor is elected and qualified. Each of the nominees, other than Mr. Hester, was elected to his or her present term of office at the 20132014 Annual Meeting. Mr. Maffie will not be nominated for reelection at this year’s Annual Meeting, and Mr. Hester will join the Board, if elected. As a result, the number of authorized directors under the Company’s bylaws will be maintained at 12.

The director nominees, as outlined below, possess core competencies in the areas of business, finance and administration and have a familiarity with regional and national business matters and the energy industry. The nominees, as a group, have integrity, varying ages, experience in accounting and construction in both residential and commercial markets and reside or do business in a cross-section of the Company’s service territories.

The 12 nominees for director receiving the highest number of votes, a plurality, will be elected to serve until the next Annual Meeting. The names of the nominees, their principal occupation and the Board’s reasons for their selection are set forth on the following pages. Except as noted, each of the nominees has held the position below his or her name for at least the past five years.

Robert L. Boughner

Executive Vice President and Chief Business Development Officer

Boyd Gaming Corporation

Director Since: 2008

Board Committees: Audit, Compensation (Chair)

Mr. Boughner, 61,62, has been in his current role with Boyd Gaming Corporation (“Boyd”) since December 2009. He has also been a director of Boyd Gaming Corporation (“Boyd”) since April 1996, a company with which he has more than 25 years of senior management experience. Additionally, from January 2009 through November 2012, Mr. Boughner served as the President and Chief Operating Officer of Marina District Development Company, LLC (“MDDC”), the limited liability company formed as part of a 50-50 joint venture betweenof Boyd and MGM Resorts International. MDDC owns and operates the Borgata Hotel Casino and Spa and the Water Club in Atlantic City, New Jersey. He also served as President and Chief Executive Officer of Boyd’s Echelon Place project, from July 2005 through the sale of the project in March 2013. Mr. Boughner had held the position of Chief Executive Officer of MDDC from January 1999 through June 2006. Prior to his initial service with MDDC, Mr. Boughner had served as Chief Operating Officer and Senior Executive Vice President of Boyd, from April 1990 and May 1998, respectively, through October 2001. He is active in civic and industry affairs and currently serves on the board of directors of Bank of Nevada.Western Alliance Bank.

The Board determined that Mr. Boughner should serve as a director of the Company because of his business and leadership experience with Boyd both in Nevada and nationally, as well as his experience as a director of Boyd and the Bank of Nevada.Western Alliance Bank.

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José A. Cárdenas

Senior Vice President and General Counsel

Arizona State University

Director Since: 2011

Board Committees: Compensation,Nominating and Corporate Governance, Pension Plan Investment

Mr. Cárdenas, 61,62, has been Senior Vice President and General Counsel for Arizona State University (“ASU”) since January 2009. In addition to serving as chief legal officer of the University, he serves as a University representative on and to the boards of directors of ASU affiliated and related entities such as the ASU Foundation. From 1982 through 2008, Mr. Cárdenas was a partner in the Phoenix based law firm of Lewis and Roca. He was the firm’s Managing Partner (CEO) from 1999 to 2003 and then the firm’s Chairman from 2003 through 2008.

Mr. Cárdenas is a native of Las Vegas, Nevada. He received his undergraduate degree from the University of Nevada, Las Vegas in 1974 and a law degree from Stanford University Law School in 1977. Mr. Cárdenas has been admitted to practice law in Arizona, California, the Ninth Circuit Court of Appeals and the United States Supreme Court and is a member of various bar associations, including the Hispanic National Bar Association. Mr. Cárdenas is a member of the boardboards of directors of Meridian Bank N.A. and Swift Transportation Company (NYSE: SWFT). His many community activities include his service as a trustee of the Virginia G. Piper Charitable Trust. He is a past chairman of the boards of Greater Phoenix Leadership, Valley of the Sun United Way, the Translational Genomics Research Institute and O’Connor House.

The Board determined that Mr. Cárdenas should serve as a director because of his business and legal experience, his leadership abilities as a trustee or chairman for a number of private foundations and institutes and his diversity.

Thomas E. Chestnut

Retired Construction Executive

Director Since: 2004

Board Committees: Audit, Pension Plan Investment

Mr. Chestnut, 63,64, was the owner, President and Chief Executive Officer of Chestnut Construction Company from 1990 until 2013. After serving in Vietnam with the U.S. Army, he began a career in the construction industry in 1972 with Del Webb Corporation. Leaving Del Webb in 1980 as Manager of Commercial Operations, Mr. Chestnut took a position with The Wray Company, a commercial contractor and wholly owned subsidiary of Weyerhaeuser Company. He remained with Wray until 1990 when he founded Chestnut Construction Company in Tucson, Arizona. Mr. Chestnut is a past president and life director of the Arizona Builders Alliance and a past president of the Arizona Building Chapter of the Associated General Contractors of America. He is a past chair and life trustee of the Carondelet Foundation, a member and past president of the Tucson Conquistadors and a member and past director of the Centurions of St. Mary’s Hospital. Mr. Chestnut was named the 2001 Tucson Small Business Leader of the Year by the Tucson Metropolitan Chamber of Commerce and the 2002 Arizona Small Business Person of the Year by the United States Small Business Administration.

The Board determined that Mr. Chestnut should serve as a director of the Company because of his business experience in the residential and commercial construction businesses, his leadership experience in managing his construction business and his commitment to civic and charitable organizations in southern Arizona. In addition, the Board has based its recommendation on his knowledge of the business and operations of the Company, resulting from his service as a director since 2004.

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Stephen C. Comer

Retired Managing Partner

Deloitte & Touche LLP

Director Since: 2007

Board Committees: Audit (Chair), Pension Plan InvestmentCompensation

Mr. Comer, 64,65, received his degree in business administration from California State University Northridge in 1972. He began his career with Arthur Andersen LLP in Los Angeles and established Arthur Andersen’s Las Vegas office, as its managing partner, in 1985. Leaving Arthur Andersen in 2002, Mr. Comer took a position as partner with Deloitte & Touche LLP and was promoted to managing partner of its Nevada practice in 2004. He retired in 2006. He serves as a director of Pinnacle Entertainment, Inc. (NYSE: PNK). He is a member of the American Institute of Certified Public Accountants and the Nevada Society of Certified Public Accountants and holds professional CPA licenses in the states of California (inactive) and Nevada. He is also involved in numerous civic, educational and charitable organizations.

The Board determined that Mr. Comer should serve as a director of the Company because of his business, accounting and auditing experience with Arthur Andersen LLP and Deloitte & Touche LLP and his leadership positions with both entities, as well as his experience as a director of Pinnacle Entertainment, Inc.

LeRoy C. Hanneman, Jr.

Retired Construction Executive

Private Investor

Director Since: 2009 (also Director September 2003 to March 2008)

Board Committees: Audit, Nominating and Corporate Governance (Chair)

Mr. Hanneman, 67,68, received his undergraduate degree in construction engineering from Arizona State University. From 2002 until his retirement in 2010, he was the Chief Executive Officer and managing member of Element Homes, L.L.C., a homebuilding and real estate development company with projects in the metropolitan Phoenix, Arizona area. Mr. Hanneman is a 35-year veteran of the housing industry and former President, Chief Operating and Executive Officer of Del Webb Corporation. Mr. Hanneman left Del Webb Corporation after its merger with Pulte Homes Corporation in 2001. He has served on a number of charitable organization boards including United Way, Boy Scouts of America and Boys & Girls Clubs of America.

The Board determined that Mr. Hanneman should serve as a director of the Company because of his business and leadership experience in the housing industry with Del Webb Corporation throughout the Company’s service territory.

John P. Hester

President and Chief Executive Officer

Southwest Gas Corporation

Director Nominee

Mr. Hester, 52, has been Chief Executive Officer since March 2015 and was named President in August 2014. Mr. Hester joined the Company in 1989, and has been named to various positions at the Company, such as Director/Regulatory Affairs and Systems Planning in 2002, Vice President/Regulatory Affairs and Systems Planning in 2003, Senior Vice President/Regulatory Affairs and Energy Resources in 2006, and Executive Vice President in 2013. Prior to joining Southwest Gas, he worked

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at the Illinois Department of Energy and Natural Resources, as well as the Illinois Commerce Commission. He received his bachelor’s and master’s degrees in Economics from Northern Illinois University. Mr. Hester currently serves on the Opportunity Village Foundation Board of Directors, the Catholic Charities of Southern Nevada Board of Trustees, the College of Southern Nevada Foundation Board of Trustees, the Las Vegas Metro Chamber Board of Trustees, the UNLV Department of Economics Executive Advisory Board, and the New Mexico State University Center for Public Utilities Advisory Council.

The Board determined that Mr. Hester should serve as a director because, as President and Chief Executive Officer of the Company, he has an intimate working knowledge of all aspects of the Company’s operations.

Anne L. Mariucci

Retired Construction Executive

Private Investor

Director Since: 2006

Board Committees: Nominating and Corporate Governance, Pension Plan Investment (Chair)

Ms. Mariucci, 57, has over 30 years of experience in homebuilding and real estate. Prior to 2003, Ms. Mariucci held a number of executive senior management roles with Del Webb Corporation and was responsible for its large-scale community development and homebuilding business. She also served as President of Del Webb following its merger with Pulte Homes, Inc. Since 2003, she has been affiliated with the private equity firms Hawkeye Partners (Austin, Texas) and Glencoe Capital (Chicago, Illinois). Ms. Mariucci received her undergraduate degree in accounting and finance from the University of Arizona and completed the corporate finance program at the Stanford University Graduate School of Business. She serves as a director of Corrections Corporation of America (NYSE:CXE), Taylor Morrison Home Corporation (NYSE: TMHC), Banner Health, the Arizona State University Foundation and the Fresh Start Women’s Foundation. Ms. Mariucci served on the Arizona Board of Regents from 2006-2014 and is its former chairman. She is a past director of the Arizona State Retirement System, Scottsdale Healthcare and Action Performance Companies, as well as a past Trustee of the Urban Land Institute.

The Board determined that Ms. Mariucci should serve as a director of the Company because of her experience as a director of other publicly traded companies, diversity and business and financial experience in the housing industry with Del Webb Corporation and Pulte Homes throughout the Company’s service territories, as well as her commitment to government, civic and charitable organizations throughout Arizona.

Michael O. MaffieJ. Melarkey

Partner

Avansino, Melarkey, Knobel, Mulligan & McKenzie

Director Since: 2004

Chairman of the Board

Board Committees: Compensation, Nominating and Corporate Governance

Mr. Melarkey, 65, a partner in the law firm of Avansino, Melarkey, Knobel, Mulligan & McKenzie for more than 35 years, received his undergraduate degree from the University of Nevada, Reno, his law degree from the University of San Francisco and his masters in laws in taxation from New York University. He has been in private legal practice in Reno, Nevada, since 1976. Mr. Melarkey is a member of the American Bar Association, the International Association of Gaming Lawyers and the State Bar of Nevada. He is a trustee of the Bretzlaff Foundation, the Robert S. and Dorothy J. Keyser

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Foundation, the Roxie and Azad Joseph Foundation and the E. L. Wiegand Trust. He is Vice President of Miami Oil Producers, Inc. and has ownership interests in the Pioneer Crossing Casino in Fernley, Nevada, the Pioneer Crossing Casino in Dayton, Nevada, and the Pioneer Crossing in Yerington, Nevada. He also serves as a director of the Gabelli Dividend & Income Trust, the Gabelli Global Utility and Income Trust, GDL Fund, the GAMCO Global Gold, Natural Resources & Income Trust by Gabelli, and the GAMCO Natural Resources, Gold & Income Trust by Gabelli, all closed-end mutual funds.

The Board determined that Mr. Melarkey should serve as a director because of his business and legal experience, his leadership abilities as a trustee for a number of private foundations and as a director of a number of closed-end mutual funds. In addition, the Board has based its recommendation on his knowledge of the business and operations of the Company, resulting from his service as a director since 2004.

Jeffrey W. Shaw

Retired Chief Executive Officer

Southwest Gas Corporation

Director Since: 1988

Board Committees: Pension Plan Investment

Mr. Maffie, 66, joined the Company in 1978 as Treasurer after seven years with Arthur Andersen & Co. He was named Vice President/Finance and Treasurer in 1982, Senior Vice President and Chief Financial Officer in 1984, Executive Vice President in 1987, President and Chief Operating Officer in 1988, and President and Chief Executive Officer in 1993. Mr. Maffie continued to serve as Chief Executive Officer until his retirement in 2004. He received his undergraduate degree in accounting and his MBA in finance from the University of Southern California. He previously served as a director of Boyd Gaming Corporation, Del Webb Corporation and Wells Fargo Bank/Nevada Division. A member of various civic and professional organizations, he served as chairman of the board of trustees of the UNLV Foundation and is a past chairman of the board of United Way of Southern Nevada. He was formerly a director of the Western Energy Institute and the American Gas Association.

The Board determined that Mr. Maffie should serve as a director of the Company because of his business and leadership experience in all aspects of the Company’s operations, his experience as a director of the Company since 1988 and other public companies, as well as his commitment to civic and charitable organizations in southern Nevada.

Anne L. Mariucci

Retired Construction Executive

Private Investor

Director Since: 2006

Board Committees: Nominating and Corporate Governance, Pension Plan Investment (Chair)

Ms. Mariucci, 56, received her undergraduate degree in accounting and finance from the University of Arizona and completed the corporate finance program at the Stanford University Graduate School of Business. She spent the majority of her professional career in the large-scale community development and homebuilding business. Ms. Mariucci was employed by Del Webb Corporation in 1984 and served in a variety of senior management capacities, culminating in President. She retired from Del Webb’s successor Pulte Homes, Inc. in 2003, became a private investor and, together with two partners, founded lnlign Capital Partners, a private equity firm investing in privately held companies. She is also affiliated with private equity firms Hawkeye Partners in Austin, Texas and Glencoe Capital in Chicago, Illinois.

Ms. Mariucci serves on the Arizona Board of Regents and is its former chairman. She also serves as a director of Corrections Corporation of America (NYSE:CXE), Taylor Morrison Home Corporation (NYSE:TMHC), the University of Arizona Health Network (UAHN), the Arizona State University Foundation and the Fresh Start Women’s Foundation. She is a past director of the Arizona State Retirement System, Scottsdale Healthcare and Action Performance Companies, as well as a past Trustee of the Urban Land Institute.

The Board determined that Ms. Mariucci should serve as a director of the Company because of her diversity and her business and financial experience in the housing industry with Del Webb Corporation and Pulte Homes throughout the Company’s service territories, as well as her commitment to government, civic and charitable organizations throughout Arizona.

Michael J. Melarkey

Partner

Avansino, Melarkey, Knobel, Mulligan & McKenzie

Director Since: 2004

Chairman of the Board

Board Committees: Compensation, Nominating and Corporate Governance

Mr. Melarkey, 64, a partner in the law firm of Avansino, Melarkey, Knobel, Mulligan & McKenzie for more than 35 years, received his undergraduate degree from the University of Nevada, Reno, his law degree from the University of San Francisco and his masters in laws in taxation from New York University. He has been in private legal practice in Reno, Nevada, since 1976. Mr. Melarkey is a member of the American Bar Association, the International Association of Gaming Lawyers and the State Bar of Nevada. He is a trustee of the Bretzlaff Foundation, the Robert S. and Dorothy J. Keyser Foundation, the Roxie and Azad Joseph Foundation and the E. L. Wiegand Trust. He is Vice President of Miami Oil Producers, Inc. and has ownership interests in the Pioneer Crossing Casino in Fernley, Nevada, the Pioneer Crossing Casino in Dayton, Nevada, and the Pioneer Crossing Casino in Yerington, Nevada. He also serves as a director of the Gabelli Dividend & Income Trust, the Gabelli Global Utility and Income Trust, GDL Fund, the GAMCO Global Gold, Natural Resources & Income Trust by Gabelli, and the GAMCO Natural Resources, Gold & Income Trust by Gabelli, all closed-end mutual funds.

The Board determined that Mr. Melarkey should serve as a director because of his business and legal experience, his leadership abilities as a trustee for a number of private foundations and as a director of a number of closed-end mutual funds. In addition, the Board has based its recommendation on his knowledge of the business and operations of the Company, resulting from his service as a director since 2004.

Jeffrey W. Shaw

President and Chief Executive Officer

Southwest Gas Corporation

Director Since: 2004

Board Committees: None

Mr. Shaw, 55,56, joined the Company in 1988 as Director of Internal Audit. He was promoted to Controller and Chief Accounting Officer in 1991, Vice President/Controller and Chief Accounting Officer in 1993, Vice President and Treasurer in 1994, Senior Vice President/Finance and Treasurer in 2000, Senior Vice President/Gas Resources and Pricing in 2002, President in 2003, Chief Executive Officer in June 2004 and President and Chief Executive Officer in July 2012. Mr. Shaw continued to serve as Chief Executive Officer until his retirement in March 2015. Mr. Shaw received his degree in accounting from the University of Utah. He has been PresidentUtah and Chief Executive Officer since July 2012. He was named Chief Executive Officer and a director of the Company in 2004. Previously, Mr. Shaw, a CPA, held various positions at the Company, including Director of Internal Audit, Controller and Chief Accounting Officer, Vice President/Controller and Chief Accounting Officer, Vice President and Treasurer, Senior Vice President/Finance and Treasurer, Senior Vice President/Gas Resources and Pricing, and President. Mr. Shaw worked for Arthur Andersen & Co., in its Dallas and Las Vegas offices prior to joining Southwest Gas. He is a member of the American Institute of Certified Public Accountants, the Nevada Society of CPAs and the Leadership Las Vegas Alumni Association. Mr. Shaw serves on the boards of the American Gas Association, National Fuel Gas (NYSE: NFG), the UNLV Foundation and the Council for a Better Nevada and the Las Vegas Economic ClubNevada; and is a past President and current board memberChairman of boththe Board of the Western Energy Institute and immediate past President of the Las Vegas Area Council of the Boy Scouts of America. In March 2014, Mr. Shaw was elected to the board of directors of National Fuel Gas Company (NYSE:NFG).

The Board determined that Mr. Shaw should serve as a director because, as President and Chief Executive Officer of the Company he has an intimate working knowledgebecause of his business and leadership experience in all aspects of the Company’s operations.

A. Randall Thoman

Retired Partner

Deloitte & Touche LLP

Director Since: 2010

Board Committees: Audit, Compensation

Mr. Thoman, 62,63, received his degree in accounting from the University of Utah and has been a Certified Public Accountant for more than 30 years. He began his career with Deloitte & Touche LLP and became a Partner in June 1991. For 15 years, Mr. Thoman was the Partner with primary responsibility for the technical interpretation and application of accounting principles and audit standards and the review of all reporting issues and financial statements for Nevada-based companies registered with the SEC. Mr. Thoman retired from Deloitte & Touche LLP in October 2009. He currently serves on the Audit Committee of SLS Hotel & Casino Las Vegas. Mr. Thoman also served on the board of SHFL Entertainment, Inc. until its acquisition in 2013.

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The Board determined that Mr. Thoman should serve as a director of the Company because of his business, accounting and auditing experience with Deloitte & Touche LLP and his leadership positions at the firm, his experience with SEC reporting and compliance, as well as his experience as a former director of several non-profit entities.

Thomas A. Thomas

Managing Partner

Thomas & Mack Co. LLC

Director Since: 2008

Board Committees: Audit, Nominating and Corporate Governance

Mr. Thomas, 56,57, received his undergraduate degree in Financefinance and his juris doctorate from the University of Utah. After obtaining his law degree, he joined Valley Bank of Nevada and held various executive positions with the bank until its merger with Bank of America in 1992. After the merger, he became managing partner of Thomas & Mack Co., an investment management and commercial real estate development company with properties and developments in Nevada, California, Arizona, and Utah. Mr. Thomas is actively involved in numerous charitable organizations including the Opportunity Village Foundation, the UNLV Foundation Advisory Board, the Las Vegas Rotary Club and the Las Vegas Area Council of the Boy Scouts of America. He is a member of the Nevada Bar Association and was instrumental in establishing the Thomas & Mack Legal Clinic and Moot Court Facility at the UNLV Boyd School of Law.

The Board determined that Mr. Thomas should serve as a director because of his banking and business experience, his familiarity with the commercial markets throughout the Company’s service territories and his commitment to civic and charitable organizations in southern Nevada.

Terrence “Terry” L. Wright

Owner/Chairman of the Board of Directors

Nevada Title Company

Director Since: 1997

Board Committees: Compensation, Nominating and Corporate Governance

Mr. Wright, 64,65, received his undergraduate degree in business administration and his juris doctorate from DePaul University. He joined Chicago Title Insurance Company while in law school and after graduation remained with the company and eventually moved to its Las Vegas, Nevada office. In 1978, he acquired the assets of Western Title to form what is now Nevada Title Company. Mr. Wright is the chairman of the board and majority owner of Westcor Land Title Insurance Company, which is licensed to issue policies of title insurance in 43 states. He is a member of the California and Illinois bar associations and has served on the board of directors for Nevada Land Title Association and the Tournament Players Club at Summerlin. He is a past chairmanpast-chairman of the Nevada Development Authority, the Nevada Chapter of the Young President’sPresidents’ Organization, the UNLV Foundation and the Council for a Better Nevada.

The Board determined that Mr. Wright should serve as a director because of his business and leadership experience with Nevada Title Company and Westcor Land Title Insurance Company, his familiarity with residential and commercial real estate markets throughout the Company’s service territories, as well as his commitment to civic and charitable organizations in southern Nevada. In addition, the Board has based its recommendation on his knowledge of the business and operations of the Company, resulting from his service as a director since 1997.

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Securities Ownership by Directors, Director Nominees, Executive Officers, and Certain Beneficial Owners

Directors, Director Nominees and Executive Officers. The following table discloses all Common Stock beneficially owned by the Company’s directors, the nominees for director and the executive officers of the Company, as of March 1, 2014.2015.

(12)

The holdings include 7,748 shares over which Mr. Hester’s spouse has voting and investment control.

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Beneficial Owners. BlackRock Inc. reported on Schedule 13G, filed on January 30, 2014,15, 2015, ownership in excess of 5% of the Company’s Common Stock. The Vanguard Group, Inc. reported on Schedule 13G, filed on February 11, 2014,2015, ownership in excess of 5% of the Company’s Common Stock. GAMCO Investors, Inc. et. al. and Gabelli Funds, LLC reported on two separate Forms 13F-HR, filed on February 7, 2014,5, 2015, ownership in excess of 5% of the Company’s Common Stock. T. Rowe Price Associates, Inc. reported on Schedule 13G, filed on February 13, 2014,11, 2015, ownership in excess of 5% of the Company’s Common Stock. The holdings of these entities on the dates noted in the filings and as a percentage of the shares outstanding on March 1, 20142015, are as follows:

Section 16(a) Beneficial Ownership Reporting Compliance

The Company has procedures in place to assist directors and executive officers in complying with Section 16(a) of the Exchange Act, which includes the preparation of forms for filing. Based upon a review of filings with the SEC and written representations that no other reports were required, we believe that all of our directors and executive officers complied during 20132014 with the reporting requirements of Section 16(a) of the Exchange Act, except the exercise of stock options with respect to 3,000 shares of Company Common Stock by director Mariucci on April 3, 2013 that was reported on Form 4 on April 9, 2013.Act.

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EXECUTIVE COMPENSATION

COMPENSATION DISCUSSION AND ANALYSIS

This Compensation Discussion and Analysis describes our 20132014 executive compensation program, the compensation decisions made by the Compensation Committee (the “committee”) under our executive compensation program, and the factors considered in making such decisions. This section focuses on the compensation of the Company’s named executive officers (“NEOs”) for fiscal 2013,2014, who were:

Executive Summary

Objectives

The objectives of our executive compensation program are to:

The Company’s 20132014 Performance

Results for the key performance measures of our natural gas operations used in the Company’s incentive-based compensation programs were as follows:

Based on our achievements, the annual incentive compensation plan paid out at 114%122% of target and the long-term incentive program, which is based on performance over the last three years, paid out at 147.5% of target.

We believe that our compensation program is successful at motivating the creation of shareholder value. The Company performed well in 20132014 and has a solid record of success over the last fiveseveral years. Performance continues to be driven by management’s steadfast focus on the core fundamentals of our businesses. Operating cash flows have remained strong and the Company’s common equity to total capitalization has improved steadily in recent years. Other recentRecent accomplishments include the following:

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Program Design

Compensation for NEOs includes:

None of the NEOs hasThe Company does not have an employment agreement with the Company.any NEO.

Base salary is designed to approximate the median (50^th percentile) of the amounts paid by peer group companies (as discussed below), and we set overall compensation to be competitive in a range between the 35^th and the 65^th percentiles of the peer group (plus or minus 15 from the median). For 2013,2014, overall total direct compensation for the NEOs, as a group, was below the median of the peer group.

Best Practices

We believe that the Company has adopted best practices for executive compensation. We annually review all elements of NEO pay and, where appropriate for the business and shareholders, make changes to incorporate current best practices. Shareholders responded with over 97%98% of the votes cast on “Say on Pay” at our 20132014 Annual Meeting in favor of the compensation of the NEOs. In keeping with best practices, we have:

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Summary of Key ChangesDevelopments in 20132014 and 20142015

Shareholders supported the Company’s executive compensation practices with a positive say-on-pay vote of over 97%98% of the votes cast at our 20132014 Annual Meeting. In light of this support, the Company did not make any materialmade limited changes to executive compensation programs in 2013 or 2014.2014 and 2015. Key developments during this period include:

The PEO’s Letter Agreement, which contained limited post-termination benefits in the event of a termination prior to the PEO’s 55^th birthday in the absence of a change in control, expired in the fourth quarter of 2013. By way of background, in late 2011 the committee,Working with the assistance ofits independent consultant, Pay Governance, an independent consultant to the committee, evaluated market practices related to post-termination benefits and those that would be appropriate for the PEO. As a result of such evaluation, in 2012 the committee recommended and the Board approved the option not to renew the PEO’s employment agreement (the “Expired Employment Agreement”) and new arrangements between the Company and the PEO, including a change in control agreement in substantially the same form as the change in control agreements with the other NEOs and the Letter Agreement.

The PEO’s Letter Agreement, which became effective June 1, 2012, provided post-termination benefits payable in the absence of a change in control of the Company upon a separation from service resulting from (i) termination without cause or (ii) as a result of a significant reduction in his duties, responsibilities, location or compensation. Upon such a termination event, the PEO would have received a lump sum cash payment equal to 12 months of base salary, plus incentive compensation for

the period during the applicable plan year preceding the date of termination and for a period of 12 months following the date of such termination. In addition, all unvested stock-based awards would have vested and stock options would have remained exercisable for 90 days after the termination event. Up to an additional year would have been provided towards the age assumption for eligibility, vesting and calculation of benefits under the Supplemental Executive Retirement Plan (“SERP”). The Letter Agreement terminated on November 9, 2013, the PEO’s 55^th birthday. Potential benefits under the change in control agreement and the Letter Agreement, respectively, were substantially less favorable to the PEO than the comparable benefits provided under the PEO’s Expired Employment Agreement.

With the termination of the Letter Agreement, the PEO’s only contractual arrangement with the Company providing for compensation following a termination event is a change in control agreement.

Key features of the PEO’s change in control agreement include:

On November 15, 2013, the Board approved revisions to the form of change in control agreement for officers (the “New Change in Control Agreement”). Except for the length of duration, the material terms and conditions of the New Change in Control Agreement are the same as those in the Company’s former change in control agreement. The Company’s former change in control agreement provided for a fixed term of three (3) years. The New Change in Control Agreement provides for a term that commences upon execution of the agreement and terminates twelve (12) months following written notice from the Company to the officer of the termination of the agreement. Pursuant to the terms of the New Change in Control Agreement, any notice of termination of the agreement will be deemed null and void if, prior to the proposed termination date, an event that was expected to result in a change in control of the Company occurs. The Company amended and restated each of the existing change in control agreements with its officers to conform to the terms and conditions of the New Change in Control Agreement.

In both January 2013 and January 2014 the committee approved changes to the NEOs variable incentive award programs under both the RSUP and the MIP for plan years beginning 2015. In order to provide direct linkage between shareholder value and executive compensation under the RSUP (the Company’s long-term incentive program), RSUP awards of all officers, starting with the three-year performance period beginning in 2015, may be adjusted, up or down, based on the Company’s total shareholder return relative to the total shareholder returns of

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peer companies. As discussed in more detail below under “Determination of the Amount to be Paid for Each Element of Compensation; Incentive Compensation; Key Changes to RSUP for 2015,” this total shareholder return “modifier” has the potential to increase the base value of RSUP awards, which will be determined in the same manner as years past, by 50% or to reduce such value by 25%. The first RSUP awards that may be adjusted by the modifier are the awards that will be granted in 2018 for the three-year performance period beginning in 2015, assuming awards are earned in respect of such performance period.

Also starting with plan year 2015, the MIP (the Company’s annual incentive program) will include two new sets of performance measures (Safety and Construction Services) in addition to the four performance measures utilized in recent years: ROE, Customer Satisfaction, Customer-to-Employee Ratio and Operating Costs. To underscore the Company’s emphasis on safety, the Committee added the Safety measure based on the Company’s performance in two categories, damages per 1,000 tickets and incident response time. For most of the Company’s officers, starting with plan year 2015, MIP awards will be based on five, equally weighted performance measures (the four measures utilized in recent years, plus Safety), with each class of performance measure accounting for 20% of the overall MIP award.

The calculation of MIP awards for Messrs. Hester, Centrella and Janov will also include a performance measure tied directly to the performance in the Company’s construction services segment. The committee added this measure in light of the recent acquisition of the Link-Line Group of Companies. For these executives, the weighting of ROE will be reduced to 10%, Construction Services will be weighted 10%, and the other four measures will be weighted 20%.

In another move related to the Link-Line acquisition, the committee approved one-time cash bonuses for certain NEOs to recognize exceptional performance related to the acquisition. This acquisition is expected to be accretive to earnings during 2015. Messrs. Shaw, Hester, Centrella and Janov received $350,000, $150,000, $75,000 and $125,000, respectively.

The committee also adjusted the mix of cash and equity that forms the MIP awards. The percentage of awards paid in equity was reduced from 60% to 40%, and the percentage paid in cash was increased to 60% from 40%. The committee made this adjustment to better align the form of the Company’s annual incentive payments with those of its peers. The foregoing changes to the MIP are discussed in more detail below under the heading, “Determination of the Amount to be Paid for Each Element of Compensation; Incentive Compensation; Key Changes to MIP for 2015.”

At mid-year 2014, the committee adopted a change to the methodology for determining executive base salaries. Historically, the Company employed the Hay Group method for salary design. In connection with the officers’ 2014 salary adjustment in July 2014, in consultation with Pay Governance, the committee relied on an approach based largely on peer company data and industry surveys. This change in methodology, while deemed conceptually significant, did not result in annual salary adjustments for the NEOs, as a group, that were out of character with the salary adjustments made in recently preceding years. It is anticipated that this new approach will carry forward through 2015.

In January 2014, as in January 2013, the committee approved incremental 2006 Restricted Stock/Unit Plan (“RSUP”)RSUP awards for each senior officer equal to 15% of base salary. These incremental awards were granted in recognition of the Company’s performance over the preceding 10 years and to motivate future performance. No such awards were granted or deemed necessary in January 2015 due, in part, to the adjustments that the committee made to the Company’s compensation programs throughout 2014 (as discussed above).

The remainder of this Compensation Discussion and Analysis offers a detailed explanation of the Company’s compensation policies and decisions with respect to the NEOs.

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Compensation Objectives

The objectives of the Company’s compensation program are to recruit, retain, reward and motivate talented executives and to align their interests with our customers and shareholders. Our executive compensation program is designed to reward performance “know-how,” “problem solving” and “accountability” and to elicit long-term employment commitments. We strive to set salary at levels that ensure reasonableness, market competitiveness and internal equity for each position. Performance awards, retirement benefit opportunities and post-termination benefits support our goal of

attracting and retaining talented executives over long-term employment commitments, while at the same time increasing shareholder value, achieving operational efficiencies and providing continued exceptional customer satisfaction.

As a public utility, the CompanyCompany’s business is a highly-regulated, entity, and the compensation itthe Company provides is evaluated as a part of the regulatory review process. Our compensation program must be responsive to market conditions and the regulatory environment we face as a public utility. Compensation costs, like all Company operating expenses, are subject to reasonableness reviews by the regulatory bodies in the states and jurisdictions in which we operate. In addition, the regulatory review process recognizes the value of providing incentives for operational efficiencies and overall customer satisfaction.

The long-term nature of the Company’s customer service obligations shapes the overall structure of the executive compensation program. We seek to ensure that long-term corporate and customer goals of safe, continuous service at reasonable rates are achieved. We also recognize that we are in a competitive environment for executives, and the compensation program has to recognize and reward performance. Non-equity incentive compensation and restricted stock-based awards are designed to address performance and provide significant support for long-term employment commitments.

The executive compensation program is prospective. The results of previously earned performance awards and the deferral of cash compensation are not taken into consideration in establishing the appropriate level of future compensation. The Company’s past performance, however, is taken into consideration in determining the long-term performance awards and in setting new performance targets.

The executive compensation program is administered by the committee. The committee annually reviews and approves the corporate goals and objectives relevant to the PEO’s compensation, the PEO’s performance in relation to such goals and objectives and, together with the other Independent Directors of the Board of Directors, the PEO’s actual compensation. The committee also reviews, together with the PEO, and approves the salaries and incentive compensation for the other executive officers.

Management annually provides information to the committee regarding what it believes to be appropriate compensation levels and performance programs and awards. This information is gathered from external independent surveys and publicly available compensation comparisons. Consultants may also be retained by management to independently assess the compensation program. Management, including the NEOs, provides guidance to, and receives direction from, the committee regarding the executive compensation program.

In addition, the committee has the authority, independent of management, to employ and retain consultants to assist it in establishing the executive compensation program objectives and in determining whether the objectives have been satisfied. The methodology used by the Company for determining executive salaries and pay increases has been reviewed by Pay Governance, an independent consultant to the committee. Pay Governance’s review encompassed all officers and indicated general approval of the methodology used. ThereAll of the “Key Developments” referenced above were no changes to the methodology usedapproved by the Company during 2013.committee in consultation with Pay Governance.

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Elements of Compensation

The executive compensation program consists of the following elements:

*

Non-equity incentive compensation;

Welfare benefits, including group life, health, hospitalization, and medical reimbursement programs, available to executive officers are the same in scope, terms and operation as the benefits available to all Company employees. Retirement benefits include both tax-qualified and nonqualified defined benefit and contribution retirement plans. Post-termination benefits are governed by change in control agreements.

Decision to Pay Each Element of Compensation

The primary objective of the executive compensation program is to elicit strong performance for customers and shareholders through the use of competitive performance-based compensation that attracts, retains and motivates high caliber executive talent. To accomplish this, the program is designed to respond to changing market conditions and to offer a broad spectrum of compensation opportunities. Performance is the critical component of the program, and both individual and overall Company performance can impact an officer’s level of compensation on an annual basis.

Salaries and performance-based compensation are linked to recognize each officer’s responsibilities and individual contribution to the success of the Company. As explained in greater detail below, an officer’s award opportunity is based on a percentage of salary and, as a result, will move in relation to changes in salary. How an officer satisfies his or her direct individual responsibilities can also impact the level of an individual officer’s performance-based compensation. Exemplary performance is expected and rewarded with the compensation elements of the program, while poor performance will result in the reduction or possible elimination of an award under our Management Incentive Plan (“MIP”).the MIP. Exceptional individual performance or significant achievements that fall outside of an NEOs core responsibilities may warrant one-time cash bonuses on occasion.

The availability of pension benefits allows the Company to deemphasize the salary component of an executive officer’s overall compensation package while still remaining competitive. The level of deferral opportunities under the Company’s qualified and nonqualified plans, however, do not influence the committee’s decisions regarding the appropriate level of overall compensation. Welfare benefits and perquisites are also viewed by the committee on a stand-alone basis, while post-termination benefits are influenced by current salary levels.

Determination of the Amount to be Paid for Each Element of Compensation

The nature of the Company’s operations and competitive considerations have led the committee to design and employ a compensation program that is comparable to compensation programs widely used in the industry by public utilities and accepted by various utility regulatory agencies. Salaries and

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performance-based compensation paid to the NEOs are determined by using a variety of sources, including Kenning Consulting for salary design and compensation surveys prepared by the American Gas Association, Towers Watson and Mercer for the components of compensation and competitive market compensation levels.

Compensation is reviewed annually and is subject to mid-year adjustment. In determining compensation for July 1, 20122014 through June 30, 2013,2015, the committee, in consultation with Pay Governance, used a compensation comparison and analysis performed by Towers Watson (“Towers Watson Study”), and an internal annual compensation comparison and analysis performed by the consultant

engaged by management. TheCompany (“2014 Company Study”). Both the Towers Watson Study and the 2014 Company Study compared the Company’s compensation packages, including base salary, total cash compensation and total direct compensation (which also includes stock-based awards under the MIP and the RSUP), to compensation data from two primary sources: (i)1) published compensation surveys that best represent the Company in the marketplace, and (ii)2) peer company proxy filings, from a peer group of comparable companies chosenprimarily developed by Towers Watson. The structures of the incentive, compensation, deferred compensation and supplemental retirement programs of the Company were also reviewed in comparison to structures of peers. Methods similar to those used in the Towers Watson Study and the 2014 Company Study were employed for the annual compensation comparison and analysis performed by the Company in 2013, which the committee used in determining compensation for July 1, 2013 through June 30, 2014.

In addition to reviewing national market surveys, the Towers Watson Study and the 2014 Company Study also included compensation comparison and analysis using proxy peer data. The peer group is composed of 1816 companies in the utility industry that are deemed to be of comparable size and to have similar basic structure and operational complexity and excludes companies with less than half or more than twice the reported revenue of the Company. The peer group, which was initially selected by Towers Watson but which now reflects the removal of three companies and the addition of one at the direction of the Company, includes the following companies:

We set base salaries for the NEOs at amounts that approximate the 50^th percentile of the amounts paid by the peer group of companies discussed above (“relevant market”). We set overall compensation to be competitive in a range between the 35^th and the 65^th percentiles of the peer group (plus or minus 15 from the median). The selection of these parameters is designed to be comparable and competitive with the relevant market to address the regulatory environment in which the Company operates and to provide a reasonable range of incentives to reward performance. The amount of one-time bonuses, when warranted, are driven by internal equity and the value of individual contributions.

Other elements of overall compensation (perquisites, welfare benefits, retirement benefits and post-termination benefits) were implemented at various times over the past several years to remain competitive with the relevant market. In determining the Company’s overall compensation, we annually compare the Company’s elements of compensation and the level of benefits with those of the relevant market to ensure the Company remains competitive. For 2013,2014, target total direct compensation, in aggregate, for the NEOs was below the median of the peer group selected for the Towers Watson Study.group.

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The material elements of management’s directions to Towers Watson in connection with their engagement for the Towers Watson Study included providing (i) management with basic market data on compensation practices, both from peer companies in the utility industry and among general industry, (ii) commentary on the current policies with respect to market practices and (iii) options to consider if it is determined that changes to current practices are needed. The committee engaged Pay Governance as an independent consultant to perform a competitive pay benchmarking analysis of the officers, independent of the Towers Watson Study. Pay Governance’s engagement with the committee also included a review of the Company’s internal director compensation comparison and analysis and

the terms of management’s change in control agreements.comparison. The Company determined that the committee’s compensation consultant did not receive fees for services, in addition to executive and director compensation services, in excess of $120,000.

For 2013,2014, the committee analyzed whether the work of any compensation advisor raised any conflict of interest, taking into consideration all relevant factors, including those set forth in Rule 10C-1(b)(4)(i) through (vi) under the Exchange Act. The committee determined, based on its analysis of all relevant factors, that no conflicts of interest were present.

Current vs. At-Risk Compensation

Total direct compensation of the Company’s NEOs, other than base salary, is at risk and must be earned by achieving annual and long-term performance goals. The portion of total direct compensation designed to be paid in base salary versus variable pay depends upon the NEO’s position and the ability of that position to influence outcomes, as well as market factors. The PEO has the largest portion of pay at risk. In 2013,2014, the percentage of targeted total direct compensation opportunity at risk or earned by achieving performance goals was approximately 69%68% for the PEO, and, for the other NEOs, the average percentage of such compensation at risk was approximately 60%.

Salaries

Salaries for the Company’s NEOs are established based on the scope of their responsibilities, taking into account competitive market compensation paid by the peer group and additional salary survey data for similar positions. Salary design is established using the Hay Group method. The Hay Group method values the substance of the positions based on “know-how,” “problem solving,” and “accountability.” Input from the Kenning Consulting (regarding salary design), the Towers Watson Study and utility and general industry surveys are used by the committee to help ensure that salaries are reasonable, competitive and properly address position responsibility. The range of salaries available through this review provides an objective standard to determine the appropriate level of salary for a given executive position. Salaries are reviewed annually and are subject to mid-year adjustment to realign salaries with market levels after taking into consideration individual responsibilities, performance, inflation and experience. Mid-year salary increases were provided to the NEOs in 20132014 based on the Company’s established compensationthis methodology.

Incentive Compensation

The performance component of the Company’s executive compensation program is designed to reward Company performance and consists of non-equity incentive compensation and restricted stock-based awards provided through the MIP and the RSUP (collectively, “Incentive Plans”). TheFor plan year 2014, the committee has designed the Incentive Plans to focus on specific annual and long-term Company financial, productivity and customer satisfaction performance goals.

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MIP

Annually, we establish incentive opportunities under the MIP, expressed as a percentage of each individual’s salary at year-end (after taking into account any mid-year salary adjustment), corresponding with each individual’s position and responsibilities with the Company, and determine the performance goals to be measured against these opportunities. For 2013,2014, the incentive opportunities for the NEOs were set at the following percentages of salary:

The performance measures for 20132014 were tied to the financial performance, productivity and customer satisfaction of the Company’s natural gas operations. This mix of performance goals is designed to address both shareholder and customer interests through the Company’s financial performance, increased productivity and customer satisfaction. In prior regulatory proceedings, the regulatory commissions have insisted that productivity measures and customer satisfaction goals be included in the MIP in order to recover any of the costs of the program through the Company’s natural gas rates.

The financial measure, ROE, is designed to reward success in reaching the average authorized return-on-equity. The productivity measures are designed to reward success in reaching a predetermined customer satisfaction percentage, a percentage improvement in the customer-to-employee ratio, and a predetermined percentage of cost containment for operating costs.

Each of the performance measures is equally weighted, and the actual performance award can range from 70% to 140% of the assigned incentive opportunity for each measure. If the threshold percentage for any measure is achieved, a percentage of annual performance awards will have been earned. Regardless of whether such awards are earned, no awards will be paid in any year unless dividends paid on our Common Stock for such year equal or exceed the prior year’s dividends.

The performance measure targets for 20132014 were as follows:

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The success in achieving the performance measures for 20132014 is discussed in the narrative following the Summary Compensation and Grants of Plan-Based Awards Tables.

The incentive opportunities as a percentage of salary for the NEOs are the same for 2014. The four performance measures used to determine whether the incentive opportunities are earned are also the same. The target for the ROE for 2014 is set at 7.81%, which represents 83% of the Company-wide authorized weighted average ROE, adjusted downward by 25 basis points to reflect the removal of Company-owned life insurance returns from consideration in the MIP. The customer satisfaction target is set at 90%, and the customer-to-employee target is set at 867 customers per employee, a 1% percent improvement over the actual ratio at the end of 2013. The operating cost target is set at 2.6%, a target that reflects estimated inflation at 1.9% and a net growth factor of 0.7%.

If annual performance awards are earned and payable, payment of the awards will be subject to a reduction depending upon satisfaction of the MIP participants’ individual performance goals. Any reductions would be tied to an individual’s overall award and not any one specific performance measure. The committee reviews the PEO’s individual performance to determine whether there will be any downward adjustment. For 2013/2014,2014/2015, individual performance goals for the PEO centered on (i) working with regulators to improve the level and stability of revenues and cash flows, (ii) striving to control operating expenses, (iii) striving to maintain/strengthen the Company’s credit ratings, (iv) pursuing actions that will, over the longer-term, improve the Company’s equity value, (v) updating the Board on the progress made on the succession plan for the CEO and key members of management and (vi) presenting strategic alternatives to the Board and pursuing agreed upon strategies.

The PEO reviews the other executive officers’ individual performances to determine whether there will be any downward adjustment in the performance awards. As a result of such review, if the PEO recommends a downward adjustment in the performance awards, the PEO will bring the matter before the committee for review and approval. There were no downward adjustments for 2013.2014. The goals of the other NEOs are designed to reflect their individual responsibilities and to complement the goals of the PEO. Mr. Centrella’s goals were centered on financial planning activities, timely, accurate and useful financial reporting, improving the Company’s credit profile, cost containment measures, and regulatory compliance. Mr. Hester’s goals were directed at improving the level and stability of revenues and cash flows through timely regulatory filings in all of our rate jurisdictions, the acquisition of gas supplies for customers, gas cost recoveries through the regulatory process, and regulatory compliance. Mr. Centrella’s goals were centered on financial planning activities, timely, accurate and useful financial reporting, improving the Company’s credit profile, cost containment measures, and regulatory compliance. Mr. Moody’s goals were focused on information systems development, cyber-security and pipeline integrity. Mr. DeBonis’Janov’s goals were directed to maintaining system safety, controlling operating costs,focused on maximizing efficient deployment of capital, developing profit improvement strategies and achieving maximum profitability on newstrategic growth. The individual performance goals for the PEO and other NEOs were satisfied, and there were no reductions in their MIP awards in respect of 2013.2014.

Further, theThe annual MIP awards will be split, withare paid in a mix of cash and equity. Awards for 2014 were paid 40% paid in cash (which are disclosed as non-equity incentive plan compensation in the Summary Compensation Table) and, with the remaining 60% converted into performance shares (which are disclosed as stock awards in the Summary Compensation and Grants of Plan-Based Awards Tables Narrative) tied to a five-day average value of the Company’s Common Stock for the first five trading days in January. The performance shares are restricted for three years, and the ultimate payout in Common Stock is subject to continued

employment during this restriction period; provided, however, that MIP performance shares vest immediately when a MIP participant retires after the age of 55 (subject to restrictions under Internal Revenue Service Code Section 409A).

Key Changes to MIP for 2015

The incentive opportunities as a percentage of salary and based on job position are the same for 2015. As discussed above under the heading, “Summary of Key Developments in 2014 and 2015,”

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however, the committee has determined that two new sets of performances measures (Safety and Construction Services) will be used to determine whether the incentive opportunities are earned for plan year 2015, in addition to the four performance measures used in 2014. The new Safety performance measures will apply to all officers, and the MIP awards of three officers, including the PEO and Chief Financial Officer, will also be determined based on a Construction Services performance measure:

The committee has also set performance targets for 2015 for the four previously utilized performance measures. The target for the ROE for 2015 is set at 7.55%, which represents 80% of the Company-wide authorized weighted average ROE, adjusted downward by 25 basis points to reflect the removal of Company-owned life insurance returns from consideration in the MIP. The customer satisfaction target is set at 90%, and the customer-to-employee target is set at 888 customers per employee, a 1% percent improvement over the actual ratio at the end of 2014. The operating cost target is set at 3.1%, a target that reflects estimated inflation at 1.9% and a net growth factor of 1.2%.

With the addition of the new performance measures, the weighting of the mix of performance measures will change for plan year 2015. For most of the Company’s officers, MIP awards will be based on five, equally weighted performance measures (ROE – 20%, Customer Satisfaction – 20%, Customer-to-Employee Ratio – 20%, Operating Costs – 20% and Safety – 20%). For the PEO, Chief Financial Officer and Senior Vice President/Corporate Development, the weighting of ROE will be reduced to 10%, Construction Services will be weighted 10%, and the other four measures will be weighted 20%.

For plan year 2015, the committee has also adjusted the mix of cash and equity that forms the MIP awards. The percentage of awards paid in equity (in the form of performance shares with the same characteristics as previous years) will be reduced from 60% to 40%, and the percentage paid in cash will be increased to 60% from 40%. The committee made this adjustment to better align the form of the Company’s annual incentive payments under the MIP with the annual incentive programs of its peers.

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RSUP

The RSUP is designed to provide incentives for maintaining long-term performance and strengthening shareholder value. The award opportunities, like that of the MIP, are based on a percentage of salary.salary and job position. For 2013,plan year 2014, the incentive opportunities for the NEOs were set at the following percentages:

The performance goal used to determine whether an award is earned is the average MIP payout percentage for the three years immediately preceding the award determination date. The target is set at an average MIP payout percentage of 100%; however, no award will be earned unless the average MIP payout percentage is at or above 90%. If an award is earned, it will be granted in the range of 50% to 150% of the incentive opportunity in the form of restricted stock or restricted stock units, based on the five-day average value of the Company’s Common Stock for the first five trading days in January. Restricted stock and/or restricted stock units vest in percentages (40%, 30% and 30%) over the three years following the date of the award; provided, however, that RSUP awards vest immediately when an RSUP participant retires after the age of 55 (subject to restrictions under Internal Revenue Service Code Section 409A). The success in achieving the performance measures for 20132014 is discussed in the narrative following the Summary Compensation and Grants of Plan-based Awards Tables.

In both January 2013 and January 2014, the committee approved incremental RSUP awards for each senior officer of the Company equal to 15% of base salary. The restricted stock units granted will vest on the same schedule as annual RSUP awards granted in the same timeframe.

Key Changes to RSUP for 2015

Starting with three-year performance period beginning in 2015, a total shareholder return “modifier” will apply to the RSUP awards of all officers, including the NEOs. Total shareholder return of the Company, comprising stock price appreciation or depreciation over three years, plus dividends, will be compared to total shareholder returns of peer companies based on the Bloomberg Transmission Distribution List. The adjustment range of the modifier will be negative 25% to positive 50% of each officer’s RSUP award (as determined according to the same plan year.methodology used to determine awards for 2014). Relative performance that places the Company in the top 25^th percentile of the peer group would result in maximum upward adjustment by 50%, performance in the range between the 25^th and 75^th percentiles would result in no adjustment, and performance below the 75^th percentile of the peer group would result in maximum downward adjustment by 25%. The factors referencedcommittee determined that the modifier should not be symmetrical because RSUP awards are 100% at risk as currently designed (e.g., if MIP payout percentages average less than 90% over the applicable three-year period, no RSUP will be earned). The modifier will be applied as of the end of the applicable three-year performance period to link the average MIP performance for each of the three years then ended with the market’s reaction to that performance. The first RSUP awards that may be adjusted by the committee when recommending thesemodifier are the awards were the incentive award criteria approved by shareholdersthat will be granted in 2018 for the RSUP.three-year performance period beginning in 2015, assuming awards are earned in respect of such performance period. Such awards will be subject to time vesting over a three-year period from the date of grant in the same manner as the 2014 awards.

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Perquisites

The Company provides a limited number of perquisites to its executive officers. The executive officers receive car allowances, cable internet access, annual $2,500 allowances for physical examinations, life insurance and a $5,000 allowance once every three years to assist in financial and estate planning. Senior officers are also provided social club memberships.

Retirement Benefits

Four retirement benefit plans are available to the executive officers. Two of the plans, the Retirement Plan for Employees of Southwest Gas Corporation (“Retirement Plan”) and the Employees’ Investment Plan (“EIP”), both tax-qualified plans, are available to all of our employees. Two additional plans are offered to the executive officers, the SERPSupplemental Executive Retirement Plan (“SERP”) and the Executive Deferral Plan (“EDP”). These additional plans were established to attract and retain qualified executive officers and to address the dollar limitations imposed on the two tax-qualified plans.

Benefits under the Retirement Plan are based on (i) the executive’s years of service with the Company, up to a maximum of 30 years, and (ii) the average of the executive’s highest five consecutive years’ salaries, within the final 10 years of service, not to exceed a maximum compensation level established by the Internal Revenue Service. The SERP is designed to supplement the benefits under the Retirement Plan to a level of 50 – 60% of salary. To qualify for benefits under the SERP, which is based on a 12-month average of the highest consecutive 36-months of salary, an executive is required to have reached (i) age 55, with 20 years of service with the Company, or (ii) age 65, with 10 years of service.

Executives may participate in the EIP and defer salary up to the maximum annual dollars permitted for 401(k) plans under the Code. Investments of these deferrals are controlled by the individual executives from a selection of investment options offered through the EIP. The Company does not match contributions for executive deferrals into the EIP. The EDP supplements the deferral opportunities by permitting executives to defer up to 100% of their annual salary and non-equity incentive compensation. As part of the EDP, the Company provides matching contributions that parallel the contributions made under the EIP to non-executives, up to 3.5% of their annual salary. Amounts deferred and Company matching contributions bear interest at 150% of the Moody’s Seasoned Corporate Bond Rate. At retirement or termination, with five years of service with the Company, the executive officers will receive EDP balances paid out at the election of the participant over a period of 10, 15, or 20 years and will be credited during the applicable payment period with interest at 150% of the average of the Moody’s Seasoned Corporate Bond Rate on each January 1^st for the five years prior to the start of retirement.

Bonuses

On rare occasions, the committee may award one-time bonuses to recognize exceptional performance or significant achievements that fall outside of an NEOs core responsibilities. In light of the recent acquisition of the Link-Line Group of Companies in the Company’s construction services segment, the committee approved one-time cash bonuses for certain NEOs in January 2015 for performances in 2014. Messrs. Shaw, Hester, Centrella and Janov received $350,000, $150,000, $75,000 and $125,000, respectively. The amounts awarded correspond to the NEOs individual contributions and personal accountability.

Post-Termination Benefits

The Company offers change in control agreements to its officers to align their interests with shareholders and to retain and motivate high caliber executive talent. Providing change in control benefits is designed to reduce the reluctance of management to pursue potential change in control

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transactions that may be in the best interests of shareholders and helps ensure stability and continued performance during the protracted process of merging with or acquiring a regulated utility. We engaged independent consultants and outside counsel to ensure that the provisions of the change in control agreements are appropriately consistent with current market practice.

As discussed under the heading “Summary of Key Changes in 2013 and 2014” above, eachEach change in control agreement provides for a term that commences upon execution of the agreement and terminates twelve (12) months following written notice from the Company to the officer of the termination of the agreement. Any notice of termination of the agreement will be deemed null and void if, prior to the proposed termination date, an event that was expected to result in a change in control of the Company occurs. The protection period for officers is 24 months after a change in control. A change in control event under the agreements is generally defined to include approval by the Company’s shareholders of the dissolution or liquidation of the Company, consummation of a merger or a similar transaction which results in more than a 50% change in ownership, acquisition by one person (or group of persons) of at least 30% of the ownership of the Company, consummation of the sale of substantially all of the Company’s business and/or assets, or the replacement of the majority of the members of the incumbent Board of Directors (excluding replacement directors nominated by the incumbent Board).

Upon a change in control event and the termination of employment without cause or as a result of a significant reduction in his duties, responsibilities, location or compensation, the officer will receive a lump-sum severance payment equal to the sum of (a) for the PEO, 36 months, for Messrs. Centrella, Hester, Moody, DeBonisJanov and other senior officers, 30 months, and for the other officers, 24 months, of annual base salary and (b) in the form of cash, an amount equal to any annual incentive compensation

calculated at 100% of the target amount payable for the same periods. Restricted stock awards, stock options and other similar awards, as well as benefits under nonqualified plans may vest and/or become exercisable upon a change in control event. In addition, at the minimum age of 50 and for purposes of determining eligibility for benefits, vesting and calculation of benefits under the SERP, Messrs. Shaw,Hester, Centrella, Hester, Moody, DeBonisJanov and other senior officers will be permitted to add six points, while all other officers will be permitted to add five points to the applicable formulas under the SERP. Finally, each officer shall be entitled to reimbursement of reasonable outplacement services not to exceed $30,000. The change in control agreements include a “double trigger” provision, which requires both a change in controland the officer’s termination of employment for good reason or the Company’s termination of the officer’s employment for reasons other than death, disability or cause, for payment of a severance benefit.

These change in control agreements have no tax gross-up provisions and instead employ a “best net” approach whereby benefits would be reduced if a reduced benefit would result in a greater after-tax benefit to the officer. If any payment under these agreements would constitute a “parachute payment” subject to any excise tax under the Code, the Company will not pay the tax on behalf of the officers.

Interaction of the Compensation Elements in Relation to the Compensation Objectives

The Company’s executive compensation program is intended to reward performance and to promote long-term employment commitments. Being rewarded for actual performance recognizes the Company’s commitments to increasing shareholder value, implementing operational efficiencies and maintaining customer satisfaction. Salary, retirement benefits and the opportunity to be rewarded for performance provide the incentive to secure long-term commitments to the Company. Taken as a whole, the program supports the Company’s commitment to its shareholders and its long-term commitment to its customers.

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Say-on-Pay

The committee attempts to balance the interests of the Company, its shareholders and customers. The Company provides an annual say-on-pay advisory vote regarding executive compensation. The Company received majority approval in 2013,2014, with more than 97%98% of the votes cast in favor of the compensation of the NEOs as described in the proxy statement for the 20132014 annual meeting. The Board and the committee reviewed the final vote results and did not make any materialmade only limited changes to the compensation policies as a result of these votes. We describe additional actions taken by the committee in 20132014 and 20142015 in the Executive Summary. We determined that our stockholders should vote on a say-on-pay proposal each year. Accordingly, the Board recommends that you vote FOR Proposal 2 at the Annual Meeting. For more information, see “ADVISORY VOTE TO APPROVE THE COMPANY’S EXECUTIVE COMPENSATION” in this Proxy Statement.

Deductibility of Compensation

Section 162(m) of the Code generally disallows a tax deduction to public companies for compensation over $1 million paid to the chief executive officer or any of the other four most highly compensated executive officers. Generally, awards under the MIP, which permits the grant of performance-based compensation, may not be subject to the deduction limit if certain requirements are met. We have also structured certain other performance-based portions of the executive compensation program in a manner that is designed to comply with the exceptions to the deductibility limitations of Section 162(m). While we intend for the performance-based compensation arrangements to meet the requirements of Section 162(m), we can provide no assurances that such compensation arrangements would ultimately satisfy such requirements.

The committee believes, however, that in certain circumstances, factors other than tax deductibility take precedence when determining the forms and levels of executive compensation most appropriate and in the best interests of the Company and its shareholders. Given our industry and business, as well as the competitive market for outstanding executives, the committee believes that it is important to retain the flexibility to design compensation programs consistent with the overall executive compensation program even if some executive compensation is not fully deductible. The committee has from time to time approved elements of compensation for certain officers that may not be fully deductible and reserves the right to do so in the future when appropriate. For example, the incremental RSUP awards granted in January 2013 and January 2014 were not designed to qualify and be fully deductible.

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COMPENSATION COMMITTEE REPORT

As a part of the committee’s duties, it is charged with the responsibility of producing a report on executive compensation for inclusion in the Annual Report on Form 10-K and this Proxy Statement. This report is based on the committee’s review of the Compensation Discussion and Analysis and the discussion of its content with management.

The committee, based on its review of the Compensation Discussion and Analysis and its discussions with management, recommended to the Board (and the Board has approved and directed) that the Compensation Discussion and Analysis be included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013,2014, and this Proxy Statement.

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Summary Compensation Table

The following table includes information concerning compensation during 2014, 2013 2012 and 20112012 for the named executive officers, whom we refer to as the “NEOs,” including our principal executive officer, the “PEO.“NEOs.”

No amounts are payable from the pension plans before a participant attains age 55 and experiences a separation in service from the Company.

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Grants of Plan-Based Awards (2013)(2014)

The following table sets forth information regarding each grant of an award made under our Incentive Plans to our NEOs during the fiscal year ended December 31, 2013.2014.

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Summary Compensation and Grants of Plan-Based Awards Tables Narrative

Salaries for the NEOs were increased in July 2013.2014. The increases in salaries reflect additional time and experience in these positions and changes to the midpoints to reflect market trends. Bonuses paid for performance in 2014 related to the acquisition of the Link-Line Group of Companies and correspond to individual contributions and accountability.

During fiscal year 2013,2014, the Company achieved 114%122% of the established target levels under the MIP, and the NEOs earned 114%122% of their respective incentive opportunities. This compares to the 20122013 and 20112012 performance results in which the Company achieved 121%114% and 122%121%, respectively, of the overall performance targets. The Company exceeded the targets for the financial performance measure (i.e., weighted average return on equity), customer service satisfaction, and customer to employee ratio and missed the target for operating cost containment. Productivity performance equaled 106% of the weighted-average return on equity, 133%128% of the customer to employee target level, 121%117% of the customer service satisfaction target level and 97%135% of the operating cost containment target level. No downward adjustments were made to the awards to the NEOs.

40% of the MIP awards were paid in cash in January 20142015 and the remaining 60% of the MIP awards were converted into performance shares in January 20142015 based on the five-day average price of Common Stock for January 2, 3,5, 6, 7 and 8, 2014,2015, which equaled $54.77$60.79 per share. The MIP cash awards paid in 20142015 for services performed in 20132014 (and included in the Summary Compensation Table) were $440,496$224,480 for Mr. Hester, $499,468 for Mr. Shaw, $107,730$133,590 for Mr. Centrella, $139,536 for Mr. Hester, $123,120$166,018 for Mr. Moody and $92,340$100,650 for Mr. DeBonis.Janov.

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The dollar value of the 20132014 MIP performance share awards, the number of performance shares granted (rounded to whole shares) as a result thereof, and the grant date fair values of the performance shares granted on January 31, 201426, 2015 are as follows:

The Company’s 20132014 performance also resulted in an award under the RSUP. The three-year average of MIP payout percentage equaled 119%, resulting in an award of 147.5% of the target and the grant of the following dollar values and numbers of restricted stock units (rounded to whole shares) to the NEOs. The dollar value of the 20132014 RSUP awards, the number of restricted stock units granted (rounded to whole shares) as a result thereof, and the grant date fair values of the performance shares granted on January 31, 201426, 2015 are as follows: