ALTA AltaBancorp

On September 17, 2021, the Board of Directors of Altabancorp^TM (the “Company”) declared a special dividend of $0.46 per share on the Company’s issued and outstanding common shares (the “Special Dividend”). The Special Dividend is payable on September 29, 2021 to holders of record as of the close of business on September 27, 2021.

The Special Dividend was declared in conjunction with the terms and conditions of that certain Plan and Agreement of Merger dated May 18, 2021 (the “Merger Agreement”) by and between the Company, its wholly owned subsidiary, Altabank^TM, Glacier Bancorp, Inc. (“GBCI”), and Glacier Bank. The merger transaction contemplated in the Merger Agreement is anticipated to close on October 1, 2021.

Caution Regarding Forward-Looking Statements

This Current Report contains forward-looking statements regarding the expected timing of completion of the transaction. Such statements are subject to numerous assumptions, risks, and uncertainties. Statements that do not describe historical or current facts, including statements about beliefs and expectations, are forward-looking statements. Forward-looking statements may be identified by words such as expect, anticipate, believe, intend, estimate, plan, target, goal, or similar expressions, or future or conditional verbs such as will, may, might, should, would, could, or similar variations. The forward-looking statements are intended to be subject to the safe harbor provided by Section 27A of the Securities Act of 1933, Section 21E of the Securities Exchange Act of 1934, and the Private Securities Litigation Reform Act of 1995.

While there is no assurance that any list of risks and uncertainties or risk factors is complete, below are certain factors which could cause actual results to differ materially from those contained or implied in the forward-looking statements: (i) changes in general economic, political, or industry conditions; (ii) the magnitude and duration of the COVID-19 pandemic and its impact on the global economy and financial market conditions and the business, results of operations, and financial condition of the Company and GBCI; (iii) uncertainty in U.S. fiscal and monetary policy, including the interest rate policies of the Federal Reserve Board; (iv) volatility and disruptions in global capital and credit markets; (v) movements in interest rates; (vi) reform of LIBOR; (vii) impacts of existing and increasing governmental regulation and related costs and liabilities; (viii) the potential existence of significant deficiencies or material weakness in our internal control over financial reporting; (ix) increased competition in the markets of the Company and GBCI; (x) the success, impact, and timing of business strategies of the Company and GBCI; (xi) the nature, extent, timing, and results of governmental actions, examinations, reviews, reforms, regulations, and interpretations; (xii) the failure to obtain necessary regulatory approvals (and the risk that such approvals may result in the imposition of conditions that could adversely affect the combined company or the expected benefits of the transaction); (xiii) the occurrence of any event, change or other circumstances that could give rise to the right of one or both of the parties to terminate the merger agreement; (xiv) the outcome

of any legal proceedings that may be instituted against the Company or GBCI; (xv) the possibility that the proposed transaction may be less accretive than expected, or may be dilutive, and the anticipated benefits of the transaction are not realized when expected or at all, including as a result of the impact of, or problems arising from, the integration of the two companies or as a result of the strength of the economy and competitive factors in the areas where the Company and GBCI do business; (xvi) the possibility that the transaction may be more expensive to complete than anticipated, including as a result of unexpected factors or events; (xvii) diversion of management’s attention from ongoing business operations and opportunities; (xviii) potential adverse reactions or changes to business or employee relationships, including those resulting from the announcement or completion of the transaction; (xix) the dilution caused by GBCI’s issuance of additional shares of its capital stock in connection with the transaction; (xx) the existence of unforeseen liabilities of the Company or GBCI; and (xxi) other factors that may affect the future results of the Company and GBCI. Additional factors that could cause results to differ materially from those described above can be found in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020, as amended, and in its subsequent Quarterly Reports on Form 10-Q, including in the respective Risk Factors sections of such reports, as well as in subsequent SEC filings, each of which is on file with the SEC and available in the “Investor Relations” section of the Company’s website, www.altabancorp.com, under the heading “SEC Filings” and in other documents the Company files with the SEC, and in GBCI’s Annual Report on Form 10-K for the year ended December 31, 2020 and in its subsequent Quarterly Reports on Form 10-Q, including in the respective Risk Factors sections of such reports, as well as in subsequent SEC filings, each of which is on file with and available in the “Corporate Information” section of GBCI’s website, www.glacierbancorp.com, under the heading “SEC Filings” and in other documents GBCI files with the SEC.

All forward-looking statements speak only as of the date they are made and are based on information available at that time. Neither the Company nor GBCI assumes any obligation to update forward-looking statements to reflect circumstances or events that occur after the date the forward-looking statements were made or to reflect the occurrence of unanticipated events except as required by federal securities laws. As forward-looking statements involve significant risks and uncertainties, caution should be exercised against placing undue reliance on such statements.