Southwest Gas : SWX May/June Investor Outreach

INVESTOR OUTREACH

Summer 2024

Safe Harbor Statement

Forward-Looking Statements

Unless context otherwise requires, in this presentation, references to "we", "us" and "our" are to Southwest Gas Holdings, Inc. (NYSE: SWX) ("Southwest Gas" or the "Company" or "SWX") together with its current and former consolidated subsidiaries, which include, among others, Southwest Gas Corporation ("Southwest", "SWG", "Utility" or "Natural Gas Distribution" segment), MountainWest Pipelines Holding Company ("MountainWest", "MW" or "Pipelines and Storage" segment), Centuri Holdings, Inc., Centuri Group, Inc. ("Centuri" or "Utility Infrastructure Services" segment) and Great Basin Gas Transmission Company ("Great Basin" or "GBGTC"). The following are subsidiaries of Centuri: NPL Construction Co. ("NPL"), NPL Canada Ltd. ("NPL Canada"), New England Utility Constructors, Inc. ("Neuco"), Linetec Services, LLC ("Linetec"), Riggs Distler & Company, Inc. ("Riggs Distler"), Canyon Pipeline Construction, Inc. ("Canyon"), National Powerline LLC ("National Powerline") and WSN Construction Inc. ("WSN Construction").

This presentation contains forward-looking statements within the meaning of the U.S. Private Securities Litigation Reform Act of 1995, Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Such statements include, without limitation, statements regarding the Company and the Company's expectations or intentions regarding the future. These forward-looking statements can often be identified by the use of words such as "will", "predict", "continue", "forecast", "expect", "believe", "anticipate", "outlook", "could", "target", "project", "intend", "plan", "pursue", "seek", "estimate", "should", "may" and "assume", as well as variations of such words and similar expressions referring to the future, and include (without limitation) statements regarding our expectations for our utility infrastructure services and natural gas operations, estimated future capital expenditures, projected rate base growth, O&M per customer expectations, our 2024 financial guidance and expected value drivers, 2024 - 2026 financial guidance and expected value drivers, 2024 financing plan, and expectations with respect to future dividends, expectations with respect to a separation of our remaining interests in Centuri, and the future performance of the Company, Southwest Gas Corporation and Centuri. The Company can provide no assurances that a separation of our remaining interests in Centuri will occur on the expected timeline or at all. For purposes of any forward-looking consolidated financial information at Southwest Gas, full consolidation of Centuri has been modeled in this presentation. A number of important factors affecting the business and financial results could cause actual results to differ materially from those stated in the forward-looking statements. These factors include, but are not limited to, statements regarding the proposed transaction structure and timing of a separation of our remaining interests in Centuri, the timing and impact of executing (or not executing) on such transaction alternatives, the timing and amount of rate relief, changes in rate design, customer growth rates, the effects of regulation/deregulation, tax reform and related regulatory decisions, the impacts of construction activity at Centuri, the potential for, and the impact of, a credit rating downgrade, future earnings trends, inflation, increasing interest rates, sufficiency of labor markets and similar resources, seasonal patterns, current and future litigation, the costs and effect of stockholder activism, and the impacts of stock market volatility. In addition, the Company can provide no assurance that its discussions about future operating margin, operating income, COLI earnings, interest expense, and capital expenditures of the natural gas distribution segment will occur. The Company does not assume any obligation to update the forward-looking statements, whether written or oral, that may be made from time to time, whether as a result of new information, future developments, or otherwise.

Forward-looking statements are based on assumptions which we believe are reasonable, based on current expectations and projections about future events and industry conditions and trends affecting our business. However, whether actual results and developments will conform to our expectations and predictions are subject to a number of risks and uncertainties that, among other things, could cause actual results to differ materially from those contained in the forward-looking statements, including without limitation, those discussed under the heading "Risk Factors", "Management's Discussion and Analysis of Financial Condition and Results of Operations," and "Quantitative and Qualitative Disclosure about Market Risk" in the Company's most recent Annual Report on Form 10-K and in the Company's and Southwest Gas Corporation's current and periodic reports, including our Quarterly Reports on Form 10-Q, filed from time to time with the SEC, and other reports that we file with the SEC from time to time.

New factors that could cause actual results to differ materially from those described in forward-looking statements emerge from time to time, and it is not possible for us to predict all such factors, or the extent to which any such factor or combination of factors may cause actual results to differ from those contained in any forward-looking statement. The statements in this presentation are made as of the date hereof, even if subsequently made available on our website or otherwise. We do not assume any obligation to update the forward-looking statements provided to reflect events that occur or circumstances that exist after the date on which they were made.

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Non-GAAP Measures

This presentation contains financial measures that have not been calculated in accordance with accounting principles generally accepted in the U.S. ("GAAP"). These non-GAAP measures include (i) natural gas distribution segment adjusted net income (loss), utility infrastructure services segment EBITDA and adjusted EBITDA. Management uses these non-GAAP measures internally to evaluate performance and in making financial and operational decisions. Management believes that its presentation of these measures provides investors greater transparency with respect to its results of operations and that these measures are useful for a period-to-period comparison of results. Management also believes that providing these non-GAAP financial measures helps investors evaluate the Company's operating performance, profitability, and business trends in a way that is consistent with how management evaluates such performance.

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Table of Contents

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Positioned for Sustainable Growth and Long-Term Success

Transitioning into a premier, fully regulated natural gas utility

Focused on Advancing Strategic Priorities

Centuri Separation

2024 Utility and Regulatory Strategy

Delivering Strong Results and Advancing Strategy - 1Q '24 Update

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