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 20152016 Annual Meeting of Shareholders and Proxy Statement
		Annual Meeting 20152016   May 7, 20154, 2016 – Las Vegas, Nevada

SOUTHWEST GAS CORPORATION

5241 Spring Mountain Road

Las Vegas, Nevada 89150

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS

To be Held Thursday,Wednesday, May 7, 20154, 2016

NOTICE IS HEREBY GIVEN that the Annual Meeting of Shareholders of Southwest Gas Corporation (the “Company”) will be held on Thursday,Wednesday, May 7, 2015,4, 2016, at 10:4:00 a.m.p.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 10, 2015,8, 2016, 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 2014 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, 2014, is either enclosed or2015, and the Proxy Statement and accompanying Proxy Card are enclosed.

Directions to attend the Annual Meeting and vote in person are included on the map on page M-1 of the Notice of 2016 Annual Meeting of Shareholders and Proxy Statement.

Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to be held on May 4, 2016:The proxy statement, the accompanying form of proxy card, and our Annual Report on Form 10-K for the fiscal year ended December 31, 2015, including financial statements, are available on the Internet athttp://www.swgas.com/proxymaterials.. Under rules issued by the SEC, we are providing access to our proxy materials both by sending you this full set of proxy materials and by notifying you of the availability of our proxy materials on the Internet.

Karen S. Haller

Senior Vice President/General Counsel and Corporate Secretary

March 27, 2015

NOTICE OF INTERNET AVAILABILITY OF PROXY MATERIALS·

SOUTHWEST GAS CORPORATION, 2016

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 7, 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 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 ratify the selection of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 2015 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 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 2015 Annual Meeting of Shareholders and Proxy Statement.

TABLE OF CONTENTS

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John P. Hester, President and Chief Executive Officer

March 27, 2015·, 2016

Dear Shareholders:

You are cordially invited to the Annual Meeting of Shareholders of Southwest Gas Corporation (the “Company”) scheduled to be held on Thursday,Wednesday, May 7, 2015,4, 2016, at Cili Restaurant at Bali Hai Golf Club, 5160 Las Vegas Blvd. South, Las Vegas, Nevada 89119, commencing at 10:4:00 a.m.p.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 1211 directors, to amend and reapprove the Company’s Restricted Stock/Unit Plan, to approve an amendment to the Company’s Bylaws to reduce the upper and lower limits of the range of required directors, to approve, on a non-binding advisory basis, the Company’s executive compensation, to ratify the selection of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 20152016 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 voteand to approve the amendments to the stock plan and Bylaws, executive compensation and ratify the selectionratification of PricewaterhouseCoopers LLP.our auditor.

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,

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SOUTHWEST GAS CORPORATION

5241 Spring Mountain Road •· P.O. Box 98510

·Las Vegas, Nevada 89193-8510·

PROXY STATEMENT

March 27, 2015·, 2016

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 20152016 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 27, 2015. We also will be mailing the materials to certain shareholders on or about March 27, 2015, and to those shareholders who request paper or e-mail copies of the proxy materials.•, 2016.

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 amendment and reapproval of the Company’s Restricted Stock/Unit Plan, the amendment of the Company’s Bylaws to reduce the limits of the range of required directors, the advisory approval of executive compensation, 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 10, 2015,8, 2016, 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’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 10, 2015,8, 2016, 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.

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:

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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 6, 2015,3, 2016, by mail to Wells Fargo Shareowner Services, Southwest Gas Corporation, P.O. Box 64873,64945, Saint Paul, MN 55164-9397, or by facsimile at 651-450-4026;55164-0945; 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, 46,639,02747,464,353 shares of Common Stock were outstanding and the

presence, in person or by proxy, of the holders of at least 23,319,51423,732,177 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 amendment and reapproval of the Restricted Stock/Unit Plan, the amendment to our Bylaws to reduce the limits of the required number of directors and the advisory vote to approve executive compensation isare not considered a “routine” matter.matters. 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.those matters. The ratification of the selection of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 20152016 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 amend and reapprove the Restricted Stock/Unit Plan, ratify PricewaterhouseCoopers LLP’s selection as the independent registered public accounting firm for the Company for fiscal year 20152016 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. The affirmative vote of a majority of the outstanding shares of Common Stock is necessary to approve the proposal to amend the Company’s Bylaws to reduce the upper and lower limits of the range of required directors.

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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 cumulativeCumulative 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 1211 seats on the Board.

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

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 amendment and reapproval of the Restricted Stock/Unit Plan, “FOR” the proposal to amend the Bylaws to reduce the upper and lower limits of the range of required directors, “FOR” the advisory vote to approve executive compensation and “FOR” the ratification of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 2015.2016. If you

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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, with respect to the Restricted Stock/Unit Plan or with respect to the proposal to amend the Bylaw’s and will be voted at your broker’s discretion on the ratification of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 2015.2016.

Are proxy materials available on the Internet?

The Notice of 20152016 Annual Meeting of Shareholders and Proxy Statement and the 20142015 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 majorityinstead 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.

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

WeThis year, for our Annual Meeting, all shareholders are providing certain shareholders, including shareholders who have requested to receivebeing delivered paper copies of our proxy materials. In the past, we have, from time to time, utilized SEC rules that allow companies to furnish their proxy materials with paper copiesover the Internet, and accordingly, have sent to our shareholders an Internet Availability Notice regarding Internet availability of proxy materials for those years’ annual meetings. In the future, we may again take advantage of the proxy materials instead of, orSEC rules, and in additionsuch years, will send to a Notice ofour shareholders an 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.for those years’ annual meetings.

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 goodvalid 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,$9,000, plus

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

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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:athttp://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 involvinga transaction between the Company and Switch Ltd., a company in which director Thomas has an interest. The Nominating and Corporate Governance Committee, excluding director Thomas, has reviewed the Switch transaction annually since 2011 under the Company’s policy for related person transactions, taking into account all relevant information, and as discussed further below, has determined each year that director Maffie’s status asThomas does not have a retired executive officerdirect or indirect material interest in the transaction. The primary considerations in this determination are that the transaction represents much less than 1% of Switch’s annual revenues and director Thomas’ minority ownership position in Switch. Based on the committee’s recommendation and its own review, the Board has determined that director Thomas is an Independent Director.

The Switch transaction involves the purchase by the Company of datacenter and communications-related products and services from Switch Ltd. and certain of its affiliates (“Switch”). Director Thomas owns, either directly or indirectly, an approximate 6.6% equity interest in Switch. Director Thomas’ family members own collectively, either directly or indirectly, approximately 16.25% of the Company.equity interests of Switch. We expect to pay Switch approximately $600,000 in 2016, with the potential for increased payments thereafter. In its review of the transaction, in addition to the bases for determining that director Thomas has no direct or indirect material interest in the transaction, the Nominating and Corporate Governance Committee and the Board concluded that the following facts and circumstances further support director Thomas’ independence: (i) that the commercial relationship with Switch was negotiated on an arm’s-length basis, in the ordinary course of business; (ii) that Switch is a leading provider of the services it provides to the Company and was selected by the Company’s information services department through an RFP process, without any involvement by director Thomas; (iii) the passive nature of director Thomas’ involvement in Switch, including that he is neither an officer nor employee of Switch, he is a non-managing member of Switch, and he does not have an active role in providing services to Switch; and (iv) the immaterial dollar amounts that we have paid (or are expected to pay in fiscal year 2016) to Switch and the competitive rates at which such amounts were paid (as validated by the RFP process and the rates paid for comparable services form a third party at the Company’s other datacenter facility). Additionally, the board of directors considered the nature and scope of the relationship of director Thomas’ family with Switch, which is passive in nature and does not involve any relative of director Thomas acting as an officer or employee of Switch or in any similar capacity.

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performance-based compensation that would trigger limitations under the provisions of Section 162(m) of the Code. For additional information, see “Transactions with Related Persons” below.

Board Meetings

Regular Board meetings for 2015 are scheduled for the fourth Monday of January, the fourth Tuesday of February, the fifth Friday of July, the fifth 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 meetingin 2015 and onean organizational meeting in 2014.immediately following the 2015 Annual Meeting of Shareholders. Each incumbent director attended more than 75% of the Board and committee meetings on which he or she served during 2014.2015. 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 doesconducts an in-depth assessment of potential candidates for that position. The Board believes that this leadership structure is the appropriate structure for the Company because it allows the Board to exercise true independent oversight of management. It is the Board’s intention to reelect Mr.director 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 pricing of services, authorized areas of service and 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

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, as well as regular reports on the Company’s enterprise risk management program, 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 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 ComerThoman (Chair), Boughner, Chestnut, Comer, 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

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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), Chestnut, 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 implementing and monitoring compliance programs forwith the Company.Company’s Code of Business Conduct and Ethics. The committee consists of directors Hanneman (Chair), Cárdenas, Mariucci, Melarkey, ThomasThoman 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, ChestnutShaw and Maffie.Thomas.

During 2014,2015, the Audit Committee held six meetings, the Compensation Committee held fivefour meetings, the Nominating and Corporate Governance Committee held threefour meetings and the Pension Plan Investment Committee held three meetings.

The charters for the Audit, Compensation and Nominating and Corporate Governance Committees, the Company’s Corporate Governance Guidelines and the Company’s codeCode of business conductBusiness Conduct and Ethics that applies to all employees, officers and directors are available on the Company’s website at:athttp://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., age, race, color, gender, nationalgeographic origin, ethnic background, religion, disability and disability.professional experience. 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:

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Information on the candidate’s share ownership in the Company; and

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:athttp://www.swgas.com.

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:

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The Company was engaged in two transactions withone reportable related personsperson transaction during 2014. One involves the purchase of communications-related products and services from Switch, a company in which Mr. Thomas has an interest.2015. The othertransaction 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 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 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 2013 for calendar year 2014, at anCompany’s actual cost of $155,835, and

inunder the agreement for 2015 was $150,583. In December 20142015, the agreement was renewed for the calendar year 2015,2016 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 20142015 were directors Boughner, Cárdenas,Chestnut, Comer, Melarkey, Thoman and Wright. None of the membersthese directors has ever been an officer or employee of the Company or any of its subsidiaries, and no “compensation committee interlocks” existed during 2014.2015. 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.

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Director Attendance at Annual Meetings

We normally schedule Board meetings in conjunction with each Annual Meetingannual meeting of Shareholdersshareholders and each director nominee is expected to attend the Board meetings and the Annual Meetingannual meeting of Shareholders.shareholders. Last year, all of the directors attended the 20142015 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

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.

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 20142015 Annual Meeting. The authorized number of directors is currently fixed at 12. Mr. MaffieShaw will not be nominated for reelection at this year’s Annual Meeting, and Mr. Hester will joinMeeting. As a result, the Board if elected. As a result,has determined to fix the number of authorized directors underat 11, effective upon the Company’s bylaws will be maintainedelection of directors at 12.the Annual Meeting.

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 1211 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)

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Mr. Boughner, 62,63, has been in his current role withserved as a director of the Boyd Gaming Corporation (“Boyd”) since December 2009. He has also been a director of Boyd since April 1996 a company with which heand has more than 25 years of senior management experience.experience with Boyd. Mr. Boughner announced that he will retire, effective summer 2016, from serving as Boyd’s Executive Vice President and Chief Business Development Officer, a position he has held since December 2009, but he will remain a member of Boyd’s board of directors following his retirement. 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 of 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. Prior to his work on Echelon, 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 servesrecently served on the board of directors of 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 Western Alliance Bank.

José A. Cárdenas

Senior Vice President and General Counsel

Arizona State University

Director Since: 2011

Board Committees: Nominating and Corporate Governance, Pension Plan Investment

Mr. Cárdenas, 62,63, 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)managing partner (chief executive) from 1999 to 2003 and then the firm’s Chairmanchairman 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 boardsboard of directors of Meridian Bank N.A. and Swift Transportation Company (NYSE: SWFT). His manyHe is active in community and charitable activities, include hisincluding 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 and his leadership abilitiesexperience as a director of Swift Transportation Company and as a trustee or chairman for a number of private foundations and institutes and his diversity.institutes.

Thomas E. Chestnut

Retired Construction Executive

Director Since: 2004

Board Committees: Audit, Pension Plan InvestmentCompensation

Mr. Chestnut, 64,65, 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.

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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.

Stephen C. Comer

Retired Managing Partner

Deloitte & Touche LLP

Director Since: 2007

Board Committees: Audit, (Chair), Compensation

Mr. Comer, 65,66, 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, 68,69, 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 NomineeSince: 2015

Board Committees: None

Mr. Hester, 52,53, has been President and 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

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 Economicseconomics 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 and the Las Vegas Metro Chamber of Commerce Board of Trustees, the UNLV Department of Economics Executive Advisory Board, and the New Mexico State University Center for Public Utilities Advisory Council.Trustees.

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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, 57,58, has over 30 years of experience in homebuilding and real estate. Prior to 2003, Ms. Mariucci held a number of senior 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. in 2001 until 2003. 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 onis a past chairman of the Arizona Board of Regents and served on the board from 2006-2014 and is its former chairman.2006 to 2014. She is a past director of the Arizona State Retirement System, Scottsdale Healthcare and Action Performance Companies, as well as a past Trusteetrustee 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 J. Melarkey

Retired Partner

Avansino, Melarkey, Knobel, Mulligan & McKenzie

Chairman and Manager

Pioneer Crossing Casinos

Director Since: 2004

Chairman of the Board

Board Committees: Compensation, Nominating and Corporate Governance

Mr. Melarkey, 65,66, was a partner in the law firm of Avansino, Melarkey, Knobel, Mulligan & McKenzie for more than 35 years until the firm’s merger in July 2015 with McDonald, Carano and Wilson, a statewide Nevada law firm (MCW). He 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 beenMr. Melarkey was actively engaged in private legal practice in Reno, Nevada since 1976.from 1976 until his firm’s merger with MCW. Following the merger, Mr. Melarkey was named Of Counsel with MCW and also became employed by the Pioneer Crossing Casinos as Chairman and Manager. Mr. Melarkey is a former member of the American Bar Association and the International Association of Gaming Lawyers and is licensed to practice law in 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 Bancroft Fund, Ltd., the Ellsworth Growth and Income Fund, Ltd., 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: 200413

Board Committees: None

Mr. Shaw, 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 and 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 is past Chairman of the Board of the Western Energy Institute and immediate past President of the Las Vegas Area Council of the Boy Scouts of America.

The Board determined that Mr. Shaw 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 and National Fuel Gas, as well as his commitment to civic and charitable organizations in southern Nevada.

A. Randall Thoman

Retired Partner

Deloitte & Touche LLP

Director Since: 2010

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

Mr. Thoman, 63,64, 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.

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 GovernancePension Plan Investment

Mr. Thomas, 57,58, received his undergraduate degree in finance 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, 65,66, 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 4348 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 Presidents’ Organization, the UNLV Foundation and the Council for a Better Nevada. Mr. Wright also serves on the board of directors of Golden Entertainment (NASDAQ: GDEN).

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

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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.

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, 2015.8, 2016.

Beneficial Owners. BlackRock Inc. reported on Schedule 13G, filed on January 15, 2015,27, 2016, ownership in excess of 5% of the Company’s Common Stock. The Vanguard Group, Inc. reported on Schedule 13G, filed on February 11, 2015,2016, 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,Form 13D, filed on February 5, 2015, ownership in excess of 5% of the Company’s Common Stock. T. Rowe Price Associates, Inc. reported on Schedule 13G, filed on FebruaryAugust 11,

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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, 2015,8, 2016, 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 20142015 with the reporting requirements of Section 16(a) of the Exchange Act.

EXECUTIVE COMPENSATION

COMPENSATION DISCUSSION AND ANALYSIS

This Compensation Discussion and Analysis describes our 20142015 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 2014,2015, who were:

Executive Summary

Objectives

The objectives of our executive compensation program are to:

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The Company’s 20142015 Incentive Compensation and Performance

ResultsOur annual incentive compensation plan (the Management Incentive Program or “MIP”) is based on performance in the five core areas set forth below, and our long-term incentive program (the Restricted Stock/Unit Plan or “RSUP”) is based on the average MIP payout for the key performance measureslast three years. If awards are earned, the MIP pays out in a range between 70% and 140% of our natural gas operations usedthe target award amount for each officer, and RSUP awards can range from between 50% to 150% of target awards. In 2015, the results in the Company’s incentive-based compensation programsfive core performance areas, each of which is weighted 20% in the overall MIP payout percentage, were as follows:

Based on our achievements, the annual incentive compensation plan paid out at 122%For most officers, including Ms. Haller and Messrs. Moody and DeBonis, these results aggregated for a MIP payout of 103% of target and an RSUP payout of 132.5% of target (based on a three-year MIP average of 113%). In addition to the long-termfive core measures set forth above, the 2015 incentive program, which isprograms for Messrs. Hester and Centrella and Shaw also included a performance measure based on our Canadian construction services operations. For these executives ROE and construction services were each weighted as 10% of the total MIP payout percentage, and each of the other four measures was weighted 20%. Below threshold results for the construction services performance overmeasure negatively impacted payouts for these NEOs, which were 93% of target for the last three years, paid out at 147.5%MIP and 125% of target.target for the RSUP (based on a three-year MIP average of 110%).

We believe that our compensation program, is successful at motivating the creation of shareholder value. The Company performed well in 2014 and has a solid record of success over the last several years. Performance continues to be driven by management’s steadfast focusfocusing on the core fundamentals of our businesses.business, has been and continues to be successful at motivating the operational and strategic achievements that foster the creation of shareholder value over the long term. 2015 was another year of strong results for the metrics emphasized by the MIP and RSUP, and the committee sees significant linkage between the Company’s achievements in these areas and the impressive record of shareholder returns over the last several years. Recent accomplishments include the following:

*

Dividends declared per share were $1.18 in 2012, $1.32 in 2013, and $1.46 in 2014.2014 and $1.62 in 2015. In February 2015,2016, the Board increased the quarterly dividend from 36.540.5 cents to 40.545 cents per share ($1.621.80 on an annual basis)basis and an 11% increase), effective with the June 20152016 payment.

Past performance has established a strong financial platform for sustainable growth into the future, and these recent accomplishments are expected to contribute to our ability to provide total shareholder returns over the long term. Going forward, we expect further alignment between executive compensation and shareholder returns as our NEOs are currently

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working through RSUP performance periods that will be subject to the total shareholder return (TSR) modifier recently implemented by the committee. The TSR modifier applies to each RSUP performance period starting with the period beginning in 2015 (to modify awards payable from and after the end of 2017).

Program Design

Compensation for NEOs includes:

None of the NEOs have employment agreements with the Company. Long-term incentive compensation and a significant portion of annual incentive compensation, when earned, are delivered as stock-based awards to align management interests with those of shareholders. Service vesting of these stock-based awards, in addition to retirement benefits, promotes long-term employment commitments. The Company does not have an employment agreement with any NEO.performance measures selected to drive achievements in the core areas of our business are designed to create appropriate alignment between the interests of management and those of our customers.

Base salary is designed to approximate the median (50^th percentile) of the amounts paid by peer group companies (as discussed below), and we seek to set overall compensation to be competitive in a range between the 35^th and the 65^th percentilesof plus or minus 15% of the peer group (plus or minus 15 from the median).median. For 2014,2015, overall total direct compensation for the NEOs, as a group, was below the median of the peer group.

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 compensation market factors and risk mitigation considerations. The principal executive officer (“PEO”) has the largest portion of pay at risk. In 2015, the percentage of targeted total direct compensation opportunity at risk or earned by achieving performance goals was approximately 64% for the PEO, and, for the other NEOs, the average percentage of such compensation at risk was approximately 52%.

Commitment to Best Practices

We believeare committed to adopting executive compensation policies that the Company has adoptedare consistent with best practices for executive compensation.practices. 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 98% of the votes cast on “Say on Pay” at our 2014 Annual Meeting in favor of the compensation of the NEOs. In keeping with best practices, we have:

*

Reviewed, analyzed and considered whether the Company’s compensation policies and practices create risks that are reasonably likely to have a material adverse effect on the Company, and concluded that no such material risks were identified;

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Summary of Key Developments in 2014 and 2015Changes to Compensation Program

Shareholders supported the Company’s executive compensation practices with a positive say-on-pay“say-on-pay” vote of over 98% of the votes cast at our 20142015 Annual Meeting. In light of this support, the Company madecommittee determined to make only limited changes to the executive compensation programs described in 2014 and 2015. Key developments during this period include:

Working with its independent consultant, Pay Governance, in November 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

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 thisFor plan year 2016, the construction services performance measure in lightwill be based on the performance of the recent acquisitionCompany’s entire construction services segment (Centuri). This is a departure from the approach to plan year 2015, when the construction services performance measure was focused exclusively on Canadian construction operations to stress the importance of the integration of the Link-Line Group of Companies.Companies following their acquisition in the fourth quarter of 2014. As in 2015, for plan year 2016, the construction services performance measure will only factor into the incentive compensation awards of a select group of the NEOs, which will include Messrs. Hester and Centrella and Ms. Haller. For these executives, the weighting of ROE will be reduced to 10%, Construction Servicesconstruction services will be weighted 10%, and the other four measurescore areas will each 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 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.

Compensation ObjectivesProgram Administration

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 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 Company’s business is highly-regulated, and the compensation the 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 ofcommittee administers 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. Management annually provides information to the committee regarding what it believes to be appropriate levels of the various elements of direct compensation (including target awards for incentive compensation), as well as the thresholds, targets and maximums of the performance measures used in the MIP. Information is gathered from Company operating data, external independent surveys and publicly available compensation comparisons.

In addition,While consultants may be retained by management to assess the compensation program, 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 bycommittee engaged Pay Governance as an independent consultant to perform a competitive pay benchmarking analysis of the committee.officers, independent from management’s recommendations. Pay Governance’s engagement with the committee also included a review encompassed all officers and indicated general approval of the methodology used. All ofCompany’s internal director compensation comparison. Pay Governance did not receive any fees from the “Key Developments” referenced above were approved byCompany for services other than the fees paid with respect to executive and director compensation services.

For 2015, the committee also analyzed whether the work of any executive compensation advisor raised any conflict of interest, taking into consideration all relevant factors, including those set forth in consultation with Pay Governance.