Page 6 - Code of Business Conduct and Ethics

CODE OVERVIEW

Southwest Gas Corporation (“Company”) has earned a strong reputation for honesty and
integrity. This outstanding reputation can only continue if the Company’s Board of Directors
(“Directors”), officers, and employees are individually committed to honesty and integrity in all
business relationships with coworkers, customers, shareholders, suppliers, contractors, and all
other members of the communities we serve and the groups with which we interact. This means
conducting business in a manner that is in accord not only with all applicable laws and regulations
but also with the highest ethical standards.

As part of this continuing commitment, the Company adopted this Code of Business Conduct and
Ethics (“Code”) to formalize and communicate the importance of:

• Full, fair, accurate, timely, and understandable disclosure in the reports and documents
the Company files with, or submits to, the Securities and Exchange Commission (“SEC”)
and in other public communications made by the Company;

• Compliance with all applicable governmental laws, rules, and regulations;
• Honest and ethical conduct, including the ethical handling of actual or apparent conflicts of

interest between personal and professional relationships;
• The prompt internal reporting of violations of this Code to the appropriate person; and
• Accountability for adherence to this Code.

References in this Code to the “Company” include all subsidiaries and affiliates of the Company
unless the subsidiary or affiliate has adopted its own Code of Business Conduct and Ethics. In
that event, the code implemented by the subsidiary or affiliate shall be substantially similar to
the Company’s Code.

Each Director and employee of the Company is, and will be held, responsible for the observance
of this Code. (Except where this Code distinguishes employees from officers, all references to
employees shall include officers.)

The Company’s Code encompasses the standards of its corporate culture. It applies to the way
we do business and recognizes our commitment to Safety, Service, and Reliability. These
standards are guidelines to define the right path to follow in order to maintain the Company’s
core values of integrity, respect, dependability, ethics, and honesty. The Code acts as a reference
to:

• Guide employee behavior and decision making;
• Support a positive and respectful workplace;
• Foster credibility and trust with customers and business partners;
• Protect the Company, its employees, its reputation, and shareholders;
• Avoid litigation and mitigate risk; and
• Prevent, detect, and respond to non-compliant conduct.

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