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 20112013 Annual Meeting of Shareholders and Proxy Statement
		Annual Meeting 20112013   May 5, 20119, 2013 – 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 5, 20119, 2013

NOTICE IS HEREBY GIVEN that the Annual Meeting of Shareholders of Southwest Gas Corporation (the “Company”) will be held on Thursday, May 5, 2011,9, 2013, at 10:00 a.m. PDT, at the Las Vegas Metro Chamber of Commerce, 6671 Las Vegas Blvd. South, Suite 300, Las Vegas, Nevada 89119-3290, for the following purposes:

The Board of Directors of the Company has established March 8, 2011,12, 2013, 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 20102012 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, 2010,2012, is either enclosed or available athttp://www.swgas.com/proxymaterials.

Karen S. Haller

Senior Vice President/General Counsel Compliance Officer and Corporate Secretary

March 21, 201127, 2013

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 5, 20119, 2013

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 5, 2011,9, 2013, at 10:00 a.m. PDT, at the Las Vegas Metro Chamber of Commerce, 6671 Las Vegas Blvd. South, Suite 300, Las Vegas, Nevada 89119-3290.

At the meeting you will be asked to elect 1112 directors, to provide a non-bindingapprove, on an advisory vote on executive compensation, to provide a non-binding advisory vote onbasis, the frequency of shareholder advisory vote onCompany’s executive compensation, to ratify the selection of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 20112013, 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 vote on executive compensation, a two-year frequency for future shareholder advisory votes onapproval of executive compensation and the selection of PricewaterhouseCoopers LLP.

The following materials are available at the website shownweb 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 20112013 Annual Meeting of Shareholders and Proxy Statement.

TABLE OF CONTENTS

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Jeffrey W. Shaw, President and Chief Executive Officer

March 21, 201127, 2013

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 5, 2011,9, 2013, at the Las Vegas Metro Chamber of Commerce, 6671 Las Vegas Blvd. South, Suite 300, Las Vegas, Nevada 89119-3290, 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 1112 directors, to provideapprove, on a non-binding advisory vote on executive compensation, to provide a non-binding advisory vote onbasis, the frequency of future shareholder advisory votes onCompany’s executive compensation, to ratify the selection of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 2011,2013, 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 in the advisory vote on executive compensation, vote for a two-year frequency for future shareholder advisory votes onto approve executive compensation 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 21, 201127, 2013

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 20112013 Annual Meeting of Shareholders and for any adjournment or postponement of the Annual Meeting. In this Proxy Statement, we refer to Southwest Gas Corporation as “the Company,” the Board of Directors as “we,” “our,” “us,” or “the Board” and the committees of the Board of Directors as the name of the specific committee or as “the committee.”

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 21, 2011.27, 2013. We also will be mailing the materials to certain shareholders on or about March 21, 2011,27, 2013, 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 advisory selection of a two-year frequency for 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 8, 2011,12, 2013, 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 thesethose 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 8, 2011,12, 2013, 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

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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 our the Company’s common stock (“Common StockStock”) you owned as of the record date for the Annual Meeting.

How do I vote?

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:

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 our Corporate SecretaryMay 8, 2013 by mail to ShareholderWells Fargo Shareowner Services, Southwest Gas Corporation, P.O. Box 98511, Las Vegas, NV 89193-8511,64873, Saint Paul, MN 55164-9873, or by facsimile at 702-871-9942;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, James J. KropidLeRoy 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.

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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, 45,803,83546,305,296 shares of our Common Stock were outstanding and the presence, in person or by proxy, of the holders of at least 22,901,91823,152,649 shares of our 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.

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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 onto approve executive compensation and the advisory vote on the frequency of future shareholder advisory votes on executive compensation 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 two advisory votes.vote to approve executive compensation. The ratification of the selection of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 20112013 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. Ratification of PricewaterhouseCoopers LLP’s selection requires theThe affirmative vote of a majority of shares of our 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). The affirmative vote of a majority of shares of our Common Stock represented is necessary to ratify PricewaterhouseCoopers LLP’s selection as the independent registered public accounting firm for the Company for fiscal year 2013 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 majorityto approve, on an advisory basis, the Company’s executive compensation. Although the result of the required quorum) on the advisory vote onto approve executive compensation will constitute approval. The advisory vote on the frequency of future shareholder advisory votes on executive compensation will be approved by a plurality of votes cast. Although the results of the votes on the advisory vote on executive compensation and the advisory vote on the frequency of future shareholder advisory votes on executive compensation areis non-binding, the Board will consider the outcome of the votesvote when making future executive compensation decisions and when deciding how often to hold advisory votes on 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 our 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?

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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 “EVERY TWO YEARS” on the advisory vote on the frequency of future shareholder advisory votes on executive compensation and “FOR” the ratification of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 2011.2013. If you hold your shares in street name“street name” and do not provide instructions to your broker, your shares will neithernot be voted in the election of directors nor on eitheror in the advisory questionvote to approve executive compensation and will be voted in your broker’s discretion on the ratification of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for fiscal year 2011.

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Are proxy materials available on the Internet?

The Notice of 20112013 Annual Meeting of Shareholders and Proxy Statement and the 20102012 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 eitherhttp://www.ematerials.com/swxorhttp://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?

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.

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The SEC has adopted rules that allow a company to deliver a single proxy statement, annual report or Notice of Internet Availability of Proxy Materials to an address shared by two or more of its shareholders. This method of delivery, known as “householding,” permits us to realize significant cost savings, reduces the amount of duplicate information shareholders receive, and reduces the environmental impact of printing and mailing documents to you. Under this process, certain shareholders will receive only one copy of our proxy materials and any additional proxy materials that are delivered until such time as one or more of these shareholders notifies us that they want to receive separate copies. Any shareholders who object to or wish to begin householding may notify ShareholderWells Fargo Shareowner Services at (702)-876-7280,1-800-468-9716, P.O. Box 98510, Las Vegas, NV 89193-8510.64854, Saint Paul, MN 55164-0854. We will send an individual copy of the proxy statement to any shareholder who revokes their consent to householding within thirty (30)30 days of our receipt of such revocation.

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?

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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.

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Who is soliciting my proxy?

Your proxy is being solicited by the Board, and wethe 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 $7,500,$8,500, 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“street name.” Morrow will reimburse them for their expenses in providing the materials to you. In addition, one or more of telephone, e-mail, facsimile or personal solicitation by our directors, officers or regular 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. We areThe Board is kept informed of the Company’s business through discussions with the Chief Executive Officer and other officers, by reviewing materials provided to usby management and by participating in Board and committee meetings.

We haveIndependence

The Board has determined that directors Boughner, Cárdenas, Chestnut, Comer, Gardner, Hanneman, Kropid, Maffie, Mariucci, Melarkey, Thoman, Thomas and Wright have no material relationships with the Company and are independent (“Independent Directors”). We haveThe 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, we havethe Board reviewed all transactions or relationships with

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the Company using a definition of “material relationships” to includethat (i) includes the criteria listed in Section 303A of the listing requirements of the NYSE and have presumed(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, above the Item 404 threshold 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 we useused are included in the Company’s Corporate Governance Guidelines, which are available on the Company’s website at:http://www.swgas.com.

WeThe Board based ourits independence determination primarily on a review of the responses of the directors and executive 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, wethe Board reviewed transactions involving director Thomas and reviewed director Maffie’s status as a retired executive officer of the Company.

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Board Meetings

Regular Board meetings for 20112013 are scheduled for the thirdfifth Tuesday of January, the fourth WednesdayTuesday of February, the first TuesdayFriday of August, the third Tuesday of September, andthe third Friday of November, and the Wednesday before the Annual Meeting of Shareholders in May. Additional meetings are called on an as-needed basis and wethe Board sometimes actacts by written consent without a meeting. An organizational meeting is also held immediately following the Annual Meeting of Shareholders. WeThe Board held six regular meetings, one special meeting and one organizational meeting in 2010.2012. Each incumbent director attended more than 75% of ourthe Board and committee meetings on which he or she served during 2010.2012. 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 JamesMichael J. Kropid,Melarkey, Chairman of the Board (the “Chair”), who is the current “Presiding Director.”

James J. Kropid and Richard M. Gardner will be retiring from the Board at the conclusion of this year’s Annual Meeting. With Mr. Kropid’s retirement, it is the Board’s intention to elect Michael J. Melarkey, Chairman of the Board, subject to his reelection as a director at this year’s meeting. Mr. Melarkey would assume these new responsibilities, including those of Presiding Director, at the organizational meeting immediately following the Annual Meeting.

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Board Leadership Structure

At the current time, theThe 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, subject to his or her election by shareholders.Board. Every three years or upon a Chair’s resignation, retirement, or failure to be re-elected to the Board by shareholders, we dothe Board does an in-depth assessment of potential candidates for that position. We believeThe Board believes that this leadership structure is the appropriate structure for the Company, since it allows usthe Board to exercise true independent oversight of management.

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 regulatory commissions is one of the key risks that wasis accepted as a part of the decision to becomebeing a public utility. The limits imposed because of this choiceon the Company as a public utility permeate the Company’sits 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.

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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 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, Compensation, Nominating and Corporate Governance and Pension Plan Investment Committees. 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 GardnerComer (Chair), Comer,Boughner, Chestnut, Hanneman, Thoman Thomas and Wright.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. WeThe Board has determined that directors Comer Gardner, Mariucci 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 usthe Board annually on such matters as directors’ fees and benefit programs, executive

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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), Comer, Hanneman, Kropid,Cárdenas, Melarkey, Thoman and Wright.

TheNominating and Corporate Governance Committee is responsible for making recommendations to usthe 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 usthe Board corporate governance principles and compliance programs for the Company. The committee consists of directors MelarkeyHanneman (Chair), Boughner, Chestnut, Gardner, Kropid,Mariucci, Melarkey, Thomas and Mariucci.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 ThomasMariucci (Chair), Cárdenas, Chestnut, Maffie, Mariucci,Comer and Thoman.Maffie.

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During 2010,2012, 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 three meetings.

The charters for the Audit, Compensation and Nominating and Corporate Governance Committees, the Company’s corporate governance guidelines,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 ourthe 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:

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The Company defines diversityWe define “diversity” in the historicala 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 candidates for directors 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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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 territory.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 retirements,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 20120 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. For this year’s Annual Meeting, the required notice must be received by the Company on or before April 16, 2011. In order to make such a nomination, a shareholder is required to include in the written notice the following:

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The Company’s Corporate Governance Guidelines provide that no director having attained the age of 72 years will be nominated for reelection or reappointment to the Board unless a majority of the Board determines that said nomination is in the best interests of the shareholders. The Board determined that it was in the best interest of the shareholders to nominate directors Kropid and Gardner for election at last year’s Annual Meeting, even though they attained the age of 72. As of the 2011 Annual meeting, directors Kropid and Gardner will be 73 years old. Anticipating the retirement of both Messrs. Kropid and Gardner, the Nominating and Corporate Governance Committee initiated a search for potential director nominee candidates for their replacement, but have found no candidates as of the date of this proxy statement. Therefore, the committee recommended that the slate of director nominees consist only of current directors. The Board adopted the committee’s recommendation, and the slate of director nominees for your consideration is listed in the proxy materials.

Shareholder Nominees

As of the date of this Proxy Statement, thereThere have been no director nominee candidatesnominees submitted by shareholders for consideration for election at this year’s Annual Meeting of Shareholders.Shareholders, and the deadline for submissions has passed.

Transactions with Related Persons

We have adopted aThe Company has written policypolicies and procedures for the review, approval orand ratification of any 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 which includes any director, executive officer, nominee for director, five percent beneficial owners or their immediate family members, 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

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reported to the Company’s general counsel,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,Corporate Governance Guidelines, is available on the Company’s website at:http://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 (if applicable), but not limited to:without limitation:

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The Company has entered into twowas engaged in three transactions with related persons.persons during 2012. One involves entering into a commercial lease for a Company payment center with an entity in which Thomas A.Mr. Thomas has an interest. The othersecond involves entering intothe purchase of communications-related products and services from Switch, a company in which Mr. Thomas has an interest. The third involves a consulting agreement with an entity owned by Dr. Joseph W. Haller, the spouse of Karen S. Haller, the Company’s General Counsel Compliance Officer and Corporate Secretary.

The lease of commercial property for a Company payment center is for five years beginningand began in 2009 at an initial monthly rental rate of approximately $6,500. There are approximately 3511 months left on the initial lease term, and the current monthly rental rate is approximately $6,745 with$7,300 following the application of the annual minimum rent increase. The total of payments over the life of the lease will be approximately $423,000, plus a pro rata share of operating and other expenses. Mr. Thomas and his siblings have a twenty percent (20%)20% interest in the entity that is be leasing the commercial property to the Company, through their ownership in Thomas & Mack Co., LLC. Mr. Thomas is also a Managing Partner of the entity. The amount of property subject to the lease and annual revenues flowing through to the 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 a three-year agreement that

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was effective in 2011. Mr. Thomas owns, either directly or indirectly, an approximate 8.5% equity interest as a passive investor in SCG. Mr. Thomas’ family members own collectively, either directly or indirectly, approximately 12.2% 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 $675,000 annually until the agreement expires. 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 Ms. Haller’s spouseDr. 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 initial agreement washas been extended multiple times, including in November 2011 for 18 months,calendar year 2012, at an actual cost of $226,368. The agreement was extended in October 2009 for another 14 months through the end of 2010, at an actual cost of $185,075. The agreement was extended again$145,057, and in November 20102012 for the calendar year 2011,2013, at an expected cost of $144,000.$169,000. The Nominating and Corporate Governance Committee has determined that Ms. Haller has a direct material interest in the transaction; however, consistent with the Company’s Related Person Transaction Policy,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 Mr.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 ourthe interests of management and the Board with that of all shareholders, we havethe Company has adopted Company Common Stock ownership guidelines for the directors and Company officers.

TheEach outside directors are expecteddirector 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 and retain a minimum of 3,000 shares of our Common Stock. New outside directors elected will be expected to satisfy the share ownership guidelinesrequirement within two years of becoming a director. Managementbeginning 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 expected to purchase and retain specific share minimums tied to their positionscurrently in compliance with the Company.these guidelines.

Each Company officers are expectedofficer 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 following minimum levelsshares of ourCompany Common Stock:

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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 stockCommon Stock owned directly by the executiveofficer or their spouse (i.e., any shares over which the executivehis or his/her spouse, has voting or investment powers) and common stockCompany Common Stock held by the executiveofficer or his/his or her spouse in the Company’s 401(k) or Dividend Reinvestment Plan.

Executives, at thePlan and performance-based restricted stock units and performance shares which have been granted but are subject to time the guidelines were adopted, were given five years to reach these levels. Executives elected after the adoption of the guidelines are given seven years, and executives promoted to positions requiring a greater number of shares are given an additional two years to satisfy the applicable ownership level.vesting requirements.

Compensation Committee Interlocks and Insider Participation

Board members who served on the Compensation Committee during 20102012 were directors Chestnut, Boughner, Cárdenas, Comer, Hanneman, Kropid, Mariucci, 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 2010.2012. 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 Meeting of Shareholders and each director is expected to attend the meetings.Board meetings and the Annual Meeting of Shareholders. Last year, all of the directors attended the 20102012 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 directorsdirector 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 thatwhich were not previously forwarded will be presented and such communications will beare 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 was elected to his or her present term of office at the 2010 Annual Meeting.

Messrs. Kropid and Gardner will not be nominated for reelection at this year’s Annual Meeting. As a result, we will amend the Company’s bylaws to reduce the number of authorized directors from 13 to 11 before this year’s2012 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 1112 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 ourthe 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 (5) years.

Robert L. Boughner

Executive Vice President and Chief Business Development Officer

Boyd Gaming Corporation

Director Since: July 2008

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

Mr. Boughner, 58,60, has served as the Executive Vice President and Chief Operating Officer of Marina District Development Finance Company, Inc., since May 2010. He has also been the President and Chief Operating Officer of Marina District Development Company since January 2009, and previously served as its Chief Executive Officer from January 1999 through June 2006. Mr. Boughner has 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. In December 2009, Mr. Boughner was named Boyd’s Executive Vice President and Chief Business Development Officer. He previously served as its Chief Operating Officer and Senior Executive Vice President, from April 1990 and May 1998, respectively, through October 2001. Mr. Boughner also serves as President and Chief Executive Officer of Echelon Resorts Corporation, a wholly owned subsidiary of Boyd, which positions he has held since July 2005. From January 2009 until December 2012, he was the President and Chief Operating Officer of Marina District Development Company, and previously served as its Chief Executive Officer from January 1999 through June 2006. He is active in civic and industry affairs and currently serves on the board of directors of Bank of Nevada.

We haveThe Board determined that Mr. Boughner should serve as a director of the Company because of his business and leadership experience with Boyd Gaming Corporation both here in Nevada and nationally, as well as his experience as a director of Boyd Gaming and the Bank of Nevada.

José A. Cárdenas

Senior Vice President and General Counsel

Arizona State University

Director Since: 2011

Board Committees: Compensation, Pension Plan Investment

Mr. Cárdenas, 60, has been Senior Vice President and General Counsel for Arizona State University since January 2009. In addition to serving as chief legal officer of the University, he serves

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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 board of directors of Meridian Bank N.A. His many community activities include his service as a member of the board of directors of the Translational Genomics Research Institute, which he chaired for 10 years, and 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 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

Owner, President and CEOChief Executive Officer

Chestnut Construction Company

Director Since: 2004

Board Committees: Nominating & Corporate Governance,Audit, Pension Plan Investment

Mr. Chestnut, 60,62, has been the owner, presidentPresident and CEOChief Executive Officer of Chestnut Construction Company since 1990. 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, and a member of the Alexis de Toqueville Society of United Way of Greater Tucson.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.

We haveThe 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, we havethe Board has based ourits 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 Compensation(Chair), Pension Plan Investment

Mr. Comer, 61,63, 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

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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. 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 activeinvolved in numerous civic, educational and charitable organizations.

We haveThe 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.

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LeRoy C. Hanneman, Jr.

Retired Construction Executive

Private Investor

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

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

Mr. Hanneman, 64,66, received his undergraduate degree in construction engineering from Arizona State University. He isFrom 2002 until his retirement in 2010, he was the former chief executive officerChief 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; he retired in 2010.area. Mr. Hanneman is a 30-year35-year veteran of the housing industry and former president, chief operatingPresident, Chief Operating and executive officerExecutive 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.

We haveThe 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. In addition, we have based our recommendation on his knowledge of the business and operations of the Company, resulting from his service as a director for over 5 years.

Michael O. Maffie

Retired Chief Executive Officer

Southwest Gas Corporation

Director Since: 1988

Board Committees: Pension Plan Investment

Mr. Maffie, 63,65, 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 also iswas formerly a past director of the Western Energy Institute and the American Gas Association.

We have16

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)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, 53,55, 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

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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 Inlignlnlign 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 is chairman ofserves on the Arizona Board of Regents.Regents and is its former chairman. She also serves as a director of Scottsdale Healthcare,Corrections Corporation of America (NYSE:CXE), 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.

We haveThe 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 (Chair), Compensation

Mr. Melarkey, 61,63, a partner in the law firm of Avansino, Melarkey, Knobel, Mulligan & McKenzie for more than twenty20 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 presidentVice President of Miami Oil Producers, Inc., and has an ownership interestinterests in the Pioneer Crossing Casino in Fernley, Nevada and the Pioneer Crossing Casino in Dayton, Nevada. He also serves as a director of the Gabelli Dividend and& Income Trust, the Gabelli Global Utility and Income Trust, GDL Fund, the GabelliGAMCO Global Gold, Natural Resources & Income Trust theby Gabelli, Global Deal Fund, and the GabelliGAMCO Natural Resources, Gold and& Income Trust by Gabelli, all closed-end mutual funds.

We have17

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, we havethe Board has based ourits 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, 52,54, 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 June 2004.July 2012. Mr. Shaw received his degree in accounting from the University of Utah and

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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 and the UNLV Foundation and is past President of the Western Energy Institute and current President of the Las Vegas Area Council of the Boy Scouts of America.

We haveThe 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 knowledge of all aspects of the Company’s operations.

A. Randall Thoman

Retired Partner

Deloitte & Touche LLP

Director Since: July 2010

Board Committees: Audit, Pension Plan InvestmentCompensation

Mr. Thoman, 59,61, received his degree in accounting from the University of Utah and washas been a Certified Public Accountant for approximatelymore 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 NevadaNevada-based companies registered with the Securities and Exchange Commission.SEC. Mr. Thoman retired from Deloitte & Touche LLP in October 2009. Mr. Thoman also serves on the board of Shuffle Master,SHFL Entertainment, Inc.

We haveThe 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.

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Thomas A. Thomas

Managing Partner

Thomas & Mack Co. LLC

Director Since: September 2008

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

Mr. Thomas, 53,55, received his undergraduate degree in Finance and his juris doctordoctorate 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, in 1992, 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, Utah and Idaho. Mr. Thomas is actively involved in numerous charitable organizations including the Opportunity Village Foundation, the Utah Shakespearean Festival,UNLV Foundation Advisory Board, the Las Vegas Rotary Club Board, Safe Nestand the Las Vegas Area Council of Nevada, and the Boy Scouts of America, Las Vegas Area Council.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.

We haveThe 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.

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Terrence “Terry” L. Wright

Owner/Chairman of the Board of Directors

Nevada Title Company

Director Since: 1997

Board Committees: Audit, Compensation, Nominating and Corporate Governance

Mr. Wright, 61,63, received his undergraduate degree in business administration and his juris doctordoctorate 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 known as Nevada Title Company. Mr. Wright is the chairman of the board and majority owner of Westcor Land Title Insurance Company, with operationswhich is licensed to issue policies of title insurance in Alabama, Arizona, California, Colorado, Florida, Idaho, Montana, Nebraska, Nevada, New York, Texas, Utah, and Wyoming.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 the Las Vegas Monorail and the Tournament Players Club at Summerlin. He is a past-chairman of the Nevada Development Authority, the Nevada Chapter of the Young President’s Organization, the UNLV Foundation and the Council for a Better Nevada. Mr. Wright is also a founder and director of Service First Bank of Nevada (now Western Liberty Bancorp).

We haveThe Board determined that Mr. Wright should serve as a director because of his business and leadership experience with Nevada Title Company and Service First Bank of Nevada,Westcor Land Title Insurance Company, his familiarity with residential and commercial markets throughout the Company’s service territories, as well as his commitment to civic and charitable organizations in southern Nevada. In addition, we havethe Board has based ourits 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 our Common Stock beneficially owned by the Company’s directors, the nominees for director and the executive officers of the Company, as of March 8, 2011.1, 2013.

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Beneficial OwnersOwners. BlackRock Inc. reported on Schedule 13G, filed on February 8, 2011, that they own1, 2013, ownership in excess of 5% of ourthe Company’s Common Stock. GAMCO Investors, Inc. et. al. and Gabelli Funds, LLC reported on Formtwo separate Forms 13F-HR, filed on February 3, 2011, that it owns13, 2013, ownership in excess of 5% of our Common Stock. The Vanguard Group, Inc. reported on Schedule 13G, filed on February 10, 2011, that it owns in excess of 5% of ourthe Company’s Common Stock. T. Rowe Price Associates, Inc. reported on Schedule 13G, filed on February 11, 2011, that it owns2013, ownership in excess of 5% of ourthe Company’s Common Stock. The Vanguard Group, Inc. reported on Schedule 13G, filed on February 12, 2013, ownership in excess of 5% of the Company’s Common Stock. Goldman Sachs Asset Management reported on Schedule 13G, filed on February 14, 2013, 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 8, 20111, 2013 are as follows:

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Section 16(a) Beneficial Ownership Reporting Compliance

The Company has adopted procedures in place to assist our 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 20102012 with the reporting requirements of Section 16(a) of the Exchange Act, except for the followingpurchase of 1,500 shares of Company Common Stock by director Cárdenas on March 2, 2012 that was reported on Form 4 filings:on March 7, 2012.

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EXECUTIVE COMPENSATION

COMPENSATION DISCUSSION AND ANALYSIS

This Compensation Discussion and Analysis describes our 2012 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 2012, who were:

Executive Summary

Objectives

The objectives of our executive compensation program are to:

The Company’s 2012 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 121% of target and the long-term incentive program, which is based on performance over the last three years, paid out at 150% of target.

We believe that our compensation program is successful at motivating the creation of shareholder value. The Company performed well in 20102012 and has a solid record of performancesuccess over the last five years. This performancePerformance continues to be driven by management’s steadfast focus on the core fundamentals of our businesses. Despite the volatile and uncertain business environment in recent years, operatingOperating cash flows have remained strong and the Company’s common equity to total capitalization has improved steadily in recent years. Other recent accomplishments include the following:

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Program Design

Compensation for NEOs includes:

None of the NEOs, other than Mr. Shaw, the Company’s principal executive officer (the “PEO”), had an employment agreement with the Company during 2012. The PEO’s employment agreement expired in the second quarter of 2012 (the “Expired Employment Agreement”) and was replaced by a letter agreement (the “Letter Agreement”) containing post-termination benefits substantially less favorable to the PEO.

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 36.2% at December 31, 2005 to 50.9% at December 31, 2010. Through sensible investments in technology and ongoing operational process improvements, the ratio of customers to employeesmedian). For 2012, overall total direct compensation for the natural gas segment increased from 661 to 1 atNEOs, as a group, was 25% below the endmedian of 2005 to 782 to 1 at the end of 2010. The Company’s stock price has also recovered from the overall market downturn experienced in 2008. The Compensation Committee works to motivate creation of shareholder value through the Company’s compensation program.peer group.

Named Executive Officers (“NEOS”)Best Practices.     This section is intended

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 informincorporate current best practices. Shareholders responded with over 98% of the votes cast on “Say on Pay” at our shareholders about our 20102012 Annual Meeting in favor of the compensation of the NEOs. In keeping with best practices, we have:

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Summary of Key Changes in 2012 and 2013

Shareholders supported the Company’s executive compensation program, includingpractices with a positive say-on-pay vote of over 98% of the votes cast at our 2012 Annual Meeting. In light of this support, the Company did not make any material changes to executive compensation objectivesprograms in 2012 or 2013. Key developments during this period include:

The PEO’s Expired Employment Agreement, which contained a tax gross-up provision, expired in the second quarter of 2012. In late 2011, the committee, with the assistance of Pay Governance, an independent consultant to the committee, evaluated market practices related to post-termination benefits and policies,those that would be appropriate for the elementsPEO. As a result of compensation,such evaluation, the committee recommended and the material factors consideredBoard approved new arrangements between the Company and the PEO, including a change in making compensation decisions for ourcontrol agreement in substantially the same form as the change in control agreements with the other NEOs listed below:and the Letter Agreement providing limited post-termination benefits

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in the event of a termination prior to the PEO’s 55^th birthday in the absence of a change in control. Potential benefits under the change in control agreement and the Letter Agreement, respectively, are substantially less favorable to the PEO than the comparable benefits provided under the PEO’s Expired Employment Agreement. Both arrangements, which are discussed in more detail below, became effective on June 1, 2012.