Form 8-K - Current report

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington D.C. 20549

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FORM 8-K

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CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of report (date of earliest event reported): July 26, 2023

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FIRST INTERSTATE BANCSYSTEM, INC.

(Exact name of registrant as specified in its charter)

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Delaware

001-34653

81-0331430

(State or other jurisdiction of
incorporation or organization)

(Commission
File No.)

(IRS Employer
Identification No.)

401 North 31st Street

Billings,

59101

(Address of principal executive offices)

(zip code)


	(406)	255-5311
(Registrant’s telephone number, including area code)

	Not Applicable
(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a- 12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

* * * * *

Securities registered pursuant to Section 12(b) of the Act:


Title of each class	Trading Symbol(s)	Name of exchange on which registered
Class A common stock, $0.00001 par value	FIBK	NASDAQ

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

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Item 2.02 Results of Operations and Financial Condition.

On July 26, 2023, First Interstate BancSystem, Inc. (the “Company”) issued a press release regarding its financial results for the quarter ended June 30, 2023. A copy of the press release is furnished herewith as Exhibit 99.1 and is incorporated by reference herein. Neither the information included or incorporated by reference under this Item 2.02, nor the press release furnished herewith, shall be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934 (the “Exchange Act”) or incorporated by reference into any registration statement or other document filed pursuant to the Securities Act of 1933 (the “Securities Act”) or the Exchange Act, except as expressly set forth by specific reference in such filing.

Item 7.01 Regulation FD Disclosure.

On July 26, 2023, the Company posted a new corporate presentation (the “Presentation”) on the News and Events page of the Company’s website at https://www.fibk.com. The Presentation, which is furnished with this Current Report as Exhibit 99.2 and incorporated herein by reference, updates previously furnished presentations and provides an overview of the Company and its operations. Neither the information included or incorporated by reference under this Item 7.01, nor the Presentation furnished herewith, shall be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act or incorporated by reference into any filing under the Securities Act or the Exchange Act, except as expressly set forth by specific reference in such a filing.

Item 8.01 Other Events.

On July 26, 2023, the Company also announced that the Board of Directors of the Company declared, on July 25, 2023, a dividend of $0.47 per share, that is payable August 17, 2023 to shareholders of record of the Company as of August 7, 2023.

Item 9.01 Financial Statements and Exhibits.


(d)	Exhibit Number	Description

	99.1	Press Release dated July 26, 2023.

	99.2	Presentation

	104	Cover Page Interactive Data File (embedded within Inline XBRL document).

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: July 26, 2023



			FIRST INTERSTATE BANCSYSTEM, INC.

			By:			/s/ KEVIN P. RILEY
						Kevin P. Riley
						President and Chief Executive Officer

Exhibit 99.1

For Immediate Release

First Interstate BancSystem, Inc. Reports Second Quarter Earnings

Billings, MT - July 26, 2023 - First Interstate BancSystem, Inc. (NASDAQ: FIBK) today reported financial results for the second quarter of 2023. For the quarter, the Company reported net income of $67.0 million, or $0.65 per share, which compares to net income of $56.3 million, or $0.54 per share, for the first quarter of 2023, and net income of $64.1 million, or $0.59 per share, for the second quarter of 2022.

For the second quarter of 2022, earnings included pre-tax acquisition costs of $45.8 million, which were related to the acquisition of Great Western Bancorp, Inc. (“Great Western”), the parent company of Great Western Bank (“GWB”), which reduced earnings by $0.34 per share during that quarter. The first and second quarters of 2023 did not include comparable costs.

HIGHLIGHTS

•Net income of $67.0 million, or $0.65 per share, for the second quarter of 2023, was impacted by $1.9 million in severance expenses, or $0.01 per share, primarily a result of permanent staffing reductions related to efficiency gains in our mortgage fulfillment process.

•Overall total deposits decreased, as expected 2.2%, for the second quarter of 2023, with growth of 1.6% during the month of June 2023 offsetting seasonal declines occurring earlier in the quarter. The Company does not hold brokered deposits.

•Net interest margin, on a fully taxable equivalent (“FTE”) basis, decreased to 3.12% for the second quarter of 2023, a 24 basis point decrease from the first quarter of 2023. Excluding income related to purchase accounting accretion, the adjusted net interest margin1, on a FTE basis, decreased to 3.05% for the second quarter of 2023, a 24 basis point decrease from the first quarter of 2023.

•Loans held for investment increased $17.7 million, or an annualized 0.4% during the second quarter of 2023 compared to the first quarter of 2023. Commercial real estate loans increased $133.1 million, or an annualized 6.1%, primarily a result of construction loans transitioning to permanent financing. Loans held for investment to deposit ratio remained relatively stable at 77.5%, as of June 30, 2023, compared to 75.7% as of March 31, 2023.

•Changes in accumulated other comprehensive loss related to unrealized losses on available-for-sale securities partially offset by an increase in retained earnings resulted in book value per common share of $29.72 as of June 30, 2023, compared to $30.28 as of March 31, 2023, and $30.36 as of June 30, 2022. Tangible book value per common share1 was $18.12 as of June 30, 2023, compared to $18.57 as of March 31, 2023 and $18.92 as of June 30, 2022. As of June 30, 2023, the accumulated other comprehensive loss position is equal to $4.37 of tangible book value per common share.

“We continued to deliver solid financial performance in the second quarter in a difficult environment for banking and we are encouraged that we are beginning to see a reversion to historical trends in our deposit base,” said Kevin P. Riley, President and Chief Executive Officer of First Interstate BancSystem, Inc. “Our markets are experiencing healthy economic conditions, most notably in the tourism and agriculture industries, where we are seeing significant increases in visitors to our national parks and have sufficient moisture levels in most parts of our footprint. We are focused on staying true to our community banking model by taking care of our clients and servicing our markets, which has allowed us to continue growing our client base. Over the first half of the year we have added a significant number of net new deposit accounts, as clients look to move their banking relationship to a strong financial institution with a reputation for service.

Over the rest of the year we are moving forward as planned with a number of strategic initiatives, which includes rolling out a new suite of consumer credit cards in August. In addition, recent changes within our Mortgage department are focused on using the strength of our branch network to originate mortgages within our communities in a more efficient manner and evidence our continued commitment to managing costs. We believe these initiatives will help us to continue growing our customer base and expanding our relationships with existing customers, particularly in our newer markets, which will enable us to continue generating long-term profitable growth and further enhancing the value of our franchise,” said Mr. Riley.

1 Non-GAAP financial measure - see Non-GAAP Financial Measures included herein for a reconciliation to GAAP measures.

DIVIDEND DECLARATION

On July 25, 2023, the Company’s board of directors declared a dividend of $0.47 per common share, payable on August 17, 2023, to common stockholders of record as of August 7, 2023. The dividend equates to a 7.5% annualized yield based on the $25.21 per share average closing price of the Company’s common stock as reported on NASDAQ during the second quarter of 2023.

NET INTEREST INCOME

Net interest income decreased $20.5 million, or 8.6%, to $218.4 million, during the second quarter of 2023, compared to net interest income of $238.9 million during the first quarter of 2023 and decreased $20.6 million, or 8.6%, during the second quarter of 2023 from the second quarter of 2022, primarily due to an increase in interest expense as a result of a higher levels and costs of interest-bearing liabilities.

•Interest accretion attributable to the fair valuation of acquired loans from acquisitions contributed to net interest income during the second quarter of 2023, the first quarter of 2023, and the second quarter of 2022, in the amounts of $4.6 million, $5.2 million, and $16.7 million, respectively.

The net interest margin ratio, on an FTE basis, was 3.12% for the second quarter of 2023, compared to 3.36% reported during the first quarter of 2023, and 3.25% during the second quarter of 2022. Excluding interest accretion from the fair value of acquired loans, on a quarter-over-quarter basis, the net interest margin ratio decreased 24 basis points, primarily driven by higher short-term borrowing costs, and higher interest-bearing deposit costs, which was partially offset by loan yield expansion and a modestly favorable earning asset mix. Excluding interest accretion from the fair value of acquired loans, on a year-over-year basis, the net interest margin ratio increased two basis points, primarily as a result of increased yields on earning assets and a shift in the mix of earning assets from investment securities and cash to loans, partially offset by higher short-term borrowings and higher costs of interest-bearing liabilities.

PROVISION FOR (REDUCTION OF) CREDIT LOSSES

During the second quarter of 2023, the Company recorded a provision for credit losses of $11.7 million, including a provision for unfunded commitments of $3.0 million and reduction of the provision for credit losses for investment securities of $1.2 million. This compares to a provision for credit losses of $15.2 million during the first quarter of 2023 and a reduction of the provision for credit losses of $1.7 million during the second quarter of 2022.

For the second quarter of 2023, the allowance for credit losses included net charge-offs of $11.4 million, or an annualized 0.25% of average loans outstanding, compared to net charge-offs of $6.2 million, or an annualized 0.14% of average loans outstanding, for the first quarter of 2023, and net charge-offs of $0.3 million, or an annualized 0.01% of average loans outstanding, for the second quarter of 2022. The net charge-offs for the second quarter of 2023 were largely comprised of one construction real estate credit in a metro market.

The Company’s allowance for credit losses as a percentage of period-end loans held for investment decreased to 1.23% at June 30, 2023 from 1.24% at March 31, 2023, and decreased from 1.28% at June 30, 2022. Coverage of non-performing loans decreased to 242.0% at June 30, 2023, compared to 265.1% at March 31, 2023 and increased from 200.5% at June 30, 2022. The allowance for credit losses on off-balance sheet credit exposures increased to $20.8 million at June 30, 2023, from $17.8 million at March 31, 2023.

NON-INTEREST INCOME


For the Quarter Ended	Jun 30, 2023		Mar 31, 2023		$ Change		% Change		Jun 30, 2022		$ Change		% Change
(Dollars in millions)
Payment services revenues	$	20.1	$	18.7	$	1.4	7.5	%	$	19.5	$	0.6	3.1	%
Mortgage banking revenues	2.6		2.3		0.3		13.0		5.0		(2.4)		(48.0)
Wealth management revenues	8.8		9.0		(0.2)		(2.2)		9.3		(0.5)		(5.4)
Service charges on deposit accounts	5.8		5.2		0.6		11.5		6.3		(0.5)		(7.9)
Other service charges, commissions, and fees	2.4		2.4		—		—		3.6		(1.2)		(33.3)
Investment securities loss	(0.1)		(23.4)		23.3		(99.6)		(0.1)		—		—
Other income	4.5		2.2		2.3		104.5		6.3		(1.8)		(28.6)

Total non-interest income	$	44.1	$	16.4	$	27.7	168.9	%	$	49.9	$	(5.8)	(11.6)	%

Non-interest income was $44.1 million for the second quarter of 2023, increasing $27.7 million compared to the first quarter of 2023. The primary driver of the increase was the realized loss of $23.4 million on the disposition of available-for-sale investment securities and a reduction of $1.9 million related to the fair value of loans held for sale recognized through other income in the first quarter of 2023.

Compared to the second quarter of 2022, non-interest income decreased $5.8 million. The decrease was primarily due to decreases in mortgage banking revenues, lower overdraft fees related to the previously announced reduction to the Company’s non-sufficient funds and overdraft practices, and other income. The decrease in other income was related to gains on the sale of premises and equipment and a recovery in the credit valuation discount on derivatives acquired in the GWB acquisition during the second quarter of 2022.

NON-INTEREST EXPENSE


For the Quarter Ended	Jun 30, 2023		Mar 31, 2023		$ Change		% Change		Jun 30, 2022		$ Change		% Change
(Dollars in millions)
Salaries and wages	$	68.1	$	65.6	$	2.5	3.8	%	$	74.8	$	(6.7)	(9.0)	%
Employee benefits	19.3		22.8		(3.5)		(15.4)		19.4		(0.1)		(0.5)
Occupancy and equipment	17.3		18.4		(1.1)		(6.0)		17.0		0.3		1.8
Other intangible amortization	3.9		4.0		(0.1)		(2.5)		4.1		(0.2)		(4.9)
Other expenses	54.7		54.8		(0.1)		(0.2)		49.2		5.5		11.2
Other real estate owned expense	0.6		0.2		0.4		200.0		—		0.6		100.0
Acquisition related expenses	—		—		—		—		45.8		(45.8)		(100.0)
Total non-interest expense	$	163.9	$	165.8	$	(1.9)	(1.1)	%	$	210.3	$	(46.4)	(22.1)	%

The Company’s non-interest expense was $163.9 million for the second quarter of 2023, a decrease of $1.9 million from the first quarter of 2023. The quarter-over-quarter decrease was primarily due to a decrease in payroll taxes included within employee benefits which were partially offset by $1.9 million in severance costs primarily related to permanent staffing reductions within the mortgage group included within salaries and wages during the second quarter of 2023.

Compared to the second quarter of 2022, non-interest expense decreased by $46.4 million. The decrease is largely due to the acquisition expenses incurred during the second quarter of 2022 related to the acquisition of GWB in addition to lower incentive accruals included within salaries and wages during the second quarter of 2023. These decreases were partially offset by an increase in other expenses related to technology services, FDIC insurance premiums, and credit card rewards.

BALANCE SHEET

Total assets decreased $661.4 million, or 2.1%, to $30,976.3 million as of June 30, 2023, from $31,637.7 million as of March 31, 2023, primarily due to a decrease in investment securities and cash and cash equivalents as a result of a decline in deposits and the paydown of other borrowed funds. Total assets decreased $1,085.5 million, or 3.4%, from $32,061.8 million as of June 30, 2022, primarily due to declines in deposits and securities sold under repurchase agreements, partially offset by an increase in short-term borrowings.

Investment securities decreased $249.9 million, or 2.7%, to $9,175.6 million as of June 30, 2023, from $9,425.5 million as of March 31, 2023, and decreased $1,695.5 million, or 15.6%, from $10,871.1 million as of June 30, 2022. The decrease from June 30, 2022 was the result of the disposition of $853.0 million of investment securities during the first quarter of 2023 and normal cash flow activity and declines in fair market values during the period.

The following table presents the composition and comparison of loans held for investment as of the quarters-ended:



	June 30, 2023		March 31, 2023		$ Change		% Change		June 30, 2022		$ Change		% Change
Real Estate:
Commercial	$	8,813.9	$	8,680.8	$	133.1	1.5	%	$	7,857.7	$	956.2	12.2	%
Construction	1,836.5		1,893.0		(56.5)		(3.0)		1,759.5		77.0		4.4
Residential	2,198.3		2,191.1		7.2		0.3		2,060.4		137.9		6.7
Agricultural	755.7		769.7		(14.0)		(1.8)		821.5		(65.8)		(8.0)
Total real estate	13,604.4		13,534.6		69.8		0.5		12,499.1		1,105.3		8.8
Consumer:
Indirect	764.1		817.3		(53.2)		(6.5)		733.9		30.2		4.1
Direct and advance lines	144.0		146.9		(2.9)		(2.0)		157.3		(13.3)		(8.5)
Credit card	72.1		71.5		0.6		0.8		74.8		(2.7)		(3.6)
Total consumer	980.2		1,035.7		(55.5)		(5.4)		966.0		14.2		1.5
Commercial	3,002.7		3,028.0		(25.3)		(0.8)		3,036.0		(33.3)		(1.1)
Agricultural	688.0		660.4		27.6		4.2		672.0		16.0		2.4
Other, including overdrafts	1.7		1.6		0.1		6.3		—		1.7		100.0
Deferred loan fees and costs	(13.6)		(14.6)		1.0		(6.8)		(10.6)		(3.0)		28.3
Loans held for investment, net of deferred loan fees and costs	$	18,263.4	$	18,245.7	$	17.7	0.1	%	$	17,162.5	$	1,100.9	6.4	%

The ratio of loans held for investment to deposits increased to 77.5%, as of June 30, 2023, compared to 75.7% as of March 31, 2023, and 63.9% as of June 30, 2022.

Total deposits seasonally decreased $527.8 million, or 2.2%, to $23,579.2 million as of June 30, 2023, from $24,107.0 million as of March 31, 2023, and decreased $3,284.6 million, or 12.2%, from $26,863.8 million as of June 30, 2022, with decreases in all categories with the exception of time deposits.

Securities sold under repurchase agreements decreased $40.9 million, or 4.2%, to $929.9 million as of June 30, 2023, from $970.8 million as of March 31, 2023, and decreased $304.8 million, or 24.7%, from $1,234.7 million as of June 30, 2022. The decreases in securities sold under repurchase agreements correspond with fluctuations in the liquidity needs of the Company’s clients.

Other borrowed funds is comprised of Federal Home Loan Bank variable rate overnight and fixed rate borrowings with contractual tenors of up to five-months. Other borrowed funds decreased $121.0 million, or 4.5%, to $2,589.0 million as of June 30, 2023, from $2,710.0 million as of March 31, 2023, and increased $2,589.0 million from June 30, 2022.

Other liabilities increased $67.4 million, or 16.6%, to $473.1 million as of June 30, 2023, from $405.7 million as of March 31, 2023, primarily due to an increase in derivative liabilities of $36.5 million, interest payable of $19.8 million, and accrued salaries and employee benefits of $10.9 million. Year-over-year, other liabilities increased $65.2 million, or 16.0%, as of June 30, 2023, from $407.9 million as of June 30, 2022, primarily due to an increase in derivative liabilities of $63.6 million.

The Company is considered to be “well-capitalized” as of June 30, 2023, having exceeded all regulatory capital adequacy requirements. During the second quarter of 2023, the Company paid regular common stock dividends of approximately $48.9 million, or $0.47 per share.

CREDIT QUALITY

As of June 30, 2023, non-performing assets increased $8.5 million, or 8.6%, to $107.2 million, compared to $98.7 million as of March 31, 2023, primarily due to an increase in non-accrual loans of $5.3 million, an increase in accruing loans past due 90 days or more of $2.2 million, and an increase in property classified as other real estate owned of $1.0 million.

Criticized loans increased $20.0 million, or 3.2%, to $641.6 million as of June 30, 2023, from $621.6 million as of March 31, 2023.

NON-GAAP FINANCIAL MEASURES

In addition to results presented in accordance with accounting principles generally accepted in the United States of America, or GAAP, this press release contains the following non-GAAP financial measures that management uses to evaluate our performance relative to our capital adequacy standards: (i) tangible common stockholders’ equity; (ii) tangible assets; (iii) tangible book value per common share; (iv) tangible common stockholders’ equity to tangible assets; (v) average tangible common stockholders’ equity; (vi) return on average tangible common stockholders’ equity; and (vii) adjusted net interest margin. Tangible common stockholders’ equity is calculated as total common stockholders’ equity less goodwill and other intangible assets (excluding mortgage servicing rights). Tangible assets are calculated as total assets less goodwill and other intangible assets (excluding mortgage servicing rights). Tangible book value per common share is calculated as tangible common stockholders’ equity divided by common shares outstanding. Tangible common stockholders’ equity to tangible assets is calculated as tangible common stockholders’ equity divided by tangible assets. Average tangible common stockholders’ equity is calculated as average stockholders’ equity less average goodwill and other intangible assets (excluding mortgage servicing rights). Return on average tangible common stockholders’ equity is calculated as net income available to common shareholders divided by average tangible common stockholders’ equity. Adjusted net interest margin ratio (FTE) is calculated as adjusted net FTE interest income divided by adjusted average interest earning assets. These non-GAAP financial measures may not be comparable to similarly titled measures reported by other companies because other companies may not calculate these non-GAAP measures in the same manner. They also should not be considered in isolation or as a substitute for measures prepared in accordance with GAAP.

The Company adjusts the most directly comparable capital adequacy GAAP financial measures to the non-GAAP financial measures described in subclauses (i) through (vi) above to exclude goodwill and other intangible assets (except mortgage servicing rights). To derive the non-GAAP financial measure identified in subclause (vii) above, the Company adjusts its net interest income to include its FTE interest income and exclude purchase accounting interest accretion on acquired loans. Management believes these non-GAAP financial measures, which are intended to complement the capital ratios defined by banking regulators and to present on a consistent basis our and our acquired companies’ organic continuing operations without regard to acquisition costs and other adjustments that we consider to be unpredictable and dependent on a significant number of factors that are outside our control, are useful to investors in evaluating the Company’s performance because, as a general matter, they either do not represent an actual cash expense and are inconsistent in amount and frequency depending upon the timing and size of our acquisitions (including the size, complexity and/or volume of past acquisitions, which may drive the magnitude of acquisition related costs, but may not be indicative of the size, complexity and/or volume of future acquisitions or related costs), or they cannot be anticipated or estimated in a particular period (in particular as it relates to unexpected recovery amounts). This impacts the ratios that are important to analysts and allows investors to compare certain aspects of the Company’s capitalization to other companies.

See the Non-GAAP Financial Measures table included herein and the textual discussion for a reconciliation of the above described non-GAAP financial measures to their most directly comparable GAAP financial measures.

Cautionary Note Regarding Forward-Looking Statements and Factors that Could Affect Future Results

This press release contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, and Rule 175 promulgated thereunder, and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act, and Rule 3b-6 promulgated thereunder, that involve inherent risks and uncertainties. Any statements about our, Great Western’s or the combined company’s plans, objectives, expectations, strategies, beliefs, or future performance or events constitute forward-looking statements. Such statements are identified by words or phrases such as “believes,” “expects,” “anticipates,” “plans,” “trends,” “objectives,” “continues” or similar expressions, or future or conditional verbs such as “will,” “would,” “should,” “could,” “might,” “may,” or similar expressions. Forward-looking statements involve known and unknown risks, uncertainties, assumptions, estimates and other important factors that change over time and could cause actual results to differ materially from any results, performance or events expressed or implied by such forward-looking statements. Furthermore, the following factors, among others, may cause actual results to differ materially from current expectations in the forward-looking statements, including those set forth in this press release:

•new, or changes in, governmental regulations or policies;

•tax legislative initiatives or assessments;

•more stringent capital requirements, to the extent they may become applicable to us;

•changes in accounting standards;

•any failure to comply with applicable laws and regulations, including the Community Reinvestment Act and fair lending laws, the USA PATRIOT ACT, Office of Foreign Asset Control guidelines and requirements, the Bank Secrecy Act, and the related Financial Crimes Enforcement Network and Federal Financial Institutions Examination Council’s guidelines and regulations;

•lending and deposit risks and risks associated with sector concentrations;

•a decline in economic conditions that could reduce demand for our products and services and negatively impact the credit quality of loans;

•loan credit losses exceeding estimates;

•the soundness of other financial institutions;

•the ability to meet cash flow needs and availability of financing sources for working capital and other needs;

•a loss of deposits or a change in product mix that increases the Company’s funding costs;

•changes in interest rates;

•changes to United States trade policies, including the imposition of tariffs and retaliatory tariffs;

•competition from new or existing financial institutions and non-banks;

•variable interest rates tied to London Interbank Offered Rate that may no longer be available or may become unreliable;

•cyber-security risks, including “denial-of-service attacks,” “hacking,” and “identity theft” that could result in the disclosure of confidential information;

•privacy, information security, and data protection laws, rules, and regulations that affect or limit how we collect and use personal information;

•the potential impairment of our goodwill and other intangible assets;

•exposure to losses in collateralized loan obligation securities;

•exposure to losses in investment securities;

•our reliance on other companies that provide key components of our business infrastructure;

•events that may tarnish our reputation;

•the loss of the services of key members of our management team and directors;

•our ability to attract and retain qualified employees to operate our business;

•costs associated with repossessed properties, including environmental remediation;

•the effectiveness of our systems of internal operating controls;

•our ability to implement new technology-facilitated products and services or be successful in marketing these products and services to our clients;

•difficulties we may face in combining the operations of acquired entities or assets with our own operations or assessing the effectiveness of businesses in which we make strategic investments or with which we enter into strategic contractual relationships;

•incurrence of significant costs related to mergers and related integration activities;

•the volatility in the price and trading volume of our common stock;

•“anti-takeover” provisions and the regulations, which may make it more difficult for a third party to acquire control of us even in circumstances that could be deemed beneficial to stockholders;

•changes in our dividend policy or our ability to pay dividends;

•our common stock not being an insured deposit;

•the potential dilutive effect of future equity issuances;

•the subordination of our common stock to our existing and future indebtedness;

•the ongoing impact of the COVID-19 pandemic and the U.S., state and local government’s response to the pandemic;

•changes in general economic conditions caused by inflation, recession, acts of terrorism, and outbreak of hostilities, or other international or domestic calamities, including wars or international conflicts with respect to which the United States may or may not be directly involved, unemployment, or other economic and geopolitical factors;

•the effect of global conditions, earthquakes, volcanoes, tsunamis, floods, fires, drought, and other natural catastrophic events; and

•the impact of climate change and environmental sustainability matters.

These factors are not necessarily all the factors that could cause our actual results, performance or achievements to differ materially from those expressed in or implied by any of our forward-looking statements. Other unknown or unpredictable factors also could harm our results.

All forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by the cautionary statements set forth above and included and described in more detail in our periodic reports filed with the Securities and Exchange Commission, or SEC, under the Securities Exchange Act of 1934, as amended, under the caption “Risk Factors.” Interested parties are urged to read in their entirety such risk factors prior to making any investment decision with respect to the Company. Forward-looking statements speak only as of the date they are made and we do not undertake or assume any obligation to update publicly any of these statements to reflect actual results, new information or future events, changes in assumptions or changes in other factors affecting forward-looking statements, except to the extent required by applicable laws. If we update one or more forward-looking statements, no inference should be drawn that we will make additional updates with respect to those or other forward-looking statements.

Second Quarter 2023 Conference Call for Investors

First Interstate BancSystem, Inc. will host a conference call to discuss the results for the second quarter of 2023 at 11 a.m. Eastern Time (9 a.m. Mountain Time) on Thursday, July 27, 2023. The conference call will be accessible by telephone and through the Internet. Participants may join the call by dialing 1-888-886-7786; the access code is 88467436. To participate via the Internet, visit www.FIBK.com. The call will be recorded and made available for replay on July 27, 2023, after 1 p.m. Eastern Time (11 a.m. Mountain Time), through August 26, 2023, prior to 9 a.m. Eastern Time (7 a.m. Mountain Time), by dialing 1-877-674-7070. The replay access code is 467436. The call will also be archived on our website, www.FIBK.com, for one year.

About First Interstate BancSystem, Inc.

First Interstate BancSystem, Inc. is a financial and bank holding company focused on community banking. Incorporated in 1971 and headquartered in Billings, Montana, the Company operates banking offices, including detached drive-up facilities, in communities across Arizona, Colorado, Idaho, Iowa, Kansas, Minnesota, Missouri, Montana, Nebraska, North Dakota, Oregon, South Dakota, Washington, and Wyoming, in addition to offering online and mobile banking services. Through our bank subsidiary, First Interstate Bank, the Company delivers a comprehensive range of banking products and services to individuals, businesses, municipalities, and others throughout the Company’s market areas.

Contact:

John R. Stewart, CFA

NASDAQ: FIBK

Deputy Chief Financial Officer
First Interstate BancSystem, Inc.
(406) 255-5311
john.stewart@fib.com

www.FIBK.com

(FIBK-ER)

FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES

Consolidated Statements of Income

(Unaudited)


	Quarter Ended										% Change
(In millions, except % and per share data)	Jun 30, 2023		Mar 31, 2023		Dec 31, 2022		Sep 30, 2022		Jun 30, 2022		2Q23 vs 1Q23		2Q23 vs 2Q22
Net interest income	$	218.4	$	238.9	$	258.4	$	266.8	$	239.0	(8.6)	%	(8.6)	%
Net interest income on a fully-taxable equivalent ("FTE") basis	220.2		240.7		260.7		268.9		241.1		(8.5)		(8.7)
Provision for (reduction in) credit losses	11.7		15.2		14.7		8.4		(1.7)		(23.0)		NM
Non-interest income:
Payment services revenues	20.1		18.7		19.4		20.4		19.5		7.5		3.1
Mortgage banking revenues	2.6		2.3		2.6		2.7		5.0		13.0		(48.0)
Wealth management revenues	8.8		9.0		8.4		8.5		9.3		(2.2)		(5.4)
Service charges on deposit accounts	5.8		5.2		4.9		5.7		6.3		11.5		(7.9)
Other service charges, commissions, and fees	2.4		2.4		2.9		4.7		3.6		—		(33.3)
Total fee-based revenues	39.7		37.6		38.2		42.0		43.7		5.6		(9.2)
Investment securities loss	(0.1)		(23.4)		—		(24.2)		(0.1)		(99.6)		—
Other income	4.5		2.2		3.4		5.1		6.3		104.5		(28.6)

Total non-interest income	44.1		16.4		41.6		22.9		49.9		168.9		(11.6)
Non-interest expense:
Salaries and wages	68.1		65.6		75.4		71.9		74.8		3.8		(9.0)
Employee benefits	19.3		22.8		17.3		19.6		19.4		(15.4)		(0.5)
Occupancy and equipment	17.3		18.4		17.9		17.1		17.0		(6.0)		1.8
Other intangible amortization	3.9		4.0		4.1		4.1		4.1		(2.5)		(4.9)
Other expenses	54.7		54.8		54.5		56.5		49.2		(0.2)		11.2
Other real estate owned expense	0.6		0.2		2.2		—		—		200.0		100.0
Acquisition related expenses	—		—		3.9		4.0		45.8		—		(100.0)
Total non-interest expense	163.9		165.8		175.3		173.2		210.3		(1.1)		(22.1)
Income before income tax	86.9		74.3		110.0		108.1		80.3		17.0		8.2
Provision for income tax	19.9		18.0		24.2		22.4		16.2		10.6		22.8
Net income	$	67.0	$	56.3	$	85.8	$	85.7	$	64.1	19.0	%	4.5	%

Weighted-average basic shares outstanding	103,821		103,738		104,445		106,526		109,107		0.1	%	(4.8)	%
Weighted-average diluted shares outstanding	103,823		103,819		104,548		106,590		109,132		—		(4.9)
Earnings per share - basic	$	0.65	$	0.54	$	0.82	$	0.80	$	0.59	20.4		10.2
Earnings per share - diluted	0.65		0.54		0.82		0.80		0.59		20.4		10.2









NM - not meaningful

FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES

Consolidated Balance Sheets

(Unaudited)


											% Change
(In millions, except % and per share data)	Jun 30, 2023		Mar 31, 2023		Dec 31, 2022		Sep 30, 2022		Jun 30, 2022		2Q23 vs 1Q23		2Q23 vs 2Q22
Assets:
Cash and due from banks	$	479.0	$	332.9	$	349.2	$	390.4	$	425.3	43.9	%	12.6	%
Interest-bearing deposits in banks	201.4		747.7		521.2		201.4		633.9		(73.1)		(68.2)
Federal funds sold	0.1		0.1		0.1		0.1		0.1		—		—
Cash and cash equivalents	680.5		1,080.7		870.5		591.9		1,059.3		(37.0)		(35.8)
Securities purchased under agreement to resell	—		—		—		—		202.2		—		(100.0)
Investment securities, net	9,175.6		9,425.5		10,397.9		10,269.1		10,871.1		(2.7)		(15.6)
Investment in Federal Home Loan Bank and Federal Reserve Bank stock	210.4		214.5		198.6		131.9		107.4		(1.9)		95.9
Loans held for sale, at fair value	76.5		80.9		79.9		93.6		127.4		(5.4)		(40.0)
Loans held for investment	18,263.4		18,245.7		18,099.2		17,603.5		17,162.5		0.1		6.4
Allowance for credit losses	224.6		226.1		220.1		213.0		220.4		(0.7)		1.9
Net loans held for investment	18,038.8		18,019.6		17,879.1		17,390.5		16,942.1		0.1		6.5
Goodwill and intangible assets (excluding mortgage servicing rights)	1,218.0		1,221.9		1,225.9		1,229.0		1,232.9		(0.3)		(1.2)
Company owned life insurance	502.0		499.4		497.9		495.6		492.8		0.5		1.9
Premises and equipment	443.7		443.4		444.7		445.4		442.7		0.1		0.2
Other real estate owned	14.4		13.4		12.7		16.4		16.8		7.5		(14.3)
Mortgage servicing rights	29.8		30.1		31.1		31.8		32.1		(1.0)		(7.2)
Other assets	586.6		608.3		649.5		649.5		535.0		(3.6)		9.6
Total assets	$	30,976.3	$	31,637.7	$	32,287.8	$	31,344.7	$	32,061.8	(2.1)	%	(3.4)	%

Liabilities and stockholders' equity:
Deposits	$	23,579.2	$	24,107.0	$	25,073.6	$	25,884.8	$	26,863.8	(2.2)	%	(12.2)	%
Securities sold under repurchase agreements	929.9		970.8		1,052.9		1,075.6		1,234.7		(4.2)		(24.7)
Long-term debt	120.8		120.8		120.8		120.7		120.4		—		0.3
Other borrowed funds	2,589.0		2,710.0		2,327.0		625.0		—		(4.5)		100.0
Subordinated debentures held by subsidiary trusts	163.1		163.1		163.1		163.1		163.1		—		—
Other liabilities	473.1		405.7		476.6		470.0		407.9		16.6		16.0
Total liabilities	27,855.1		28,477.4		29,214.0		28,339.2		28,789.9		(2.2)		(3.2)
Stockholders' equity:
Common stock	2,481.4		2,478.7		2,478.2		2,477.4		2,607.9		0.1		(4.9)
Retained earnings	1,098.8		1,080.7		1,072.7		1,035.8		993.8		1.7		10.6
Accumulated other comprehensive loss	(459.0)		(399.1)		(477.1)		(507.7)		(329.8)		15.0		39.2
Total stockholders' equity	3,121.2		3,160.3		3,073.8		3,005.5		3,271.9		(1.2)		(4.6)
Total liabilities and stockholders' equity	$	30,976.3	$	31,637.7	$	32,287.8	$	31,344.7	$	32,061.8	(2.1)	%	(3.4)	%

Common shares outstanding at period end	105,021		104,382		104,442		104,451		107,758		0.6	%	(2.5)	%
Book value per common share at period end	$	29.72	$	30.28	$	29.43	$	28.77	$	30.36	(1.8)		(2.1)
Tangible book value per common share at period end**	18.12		18.57		17.69		17.01		18.92		(2.4)		(4.2)




**Non-GAAP financial measure - see Non-GAAP Financial Measures included herein for a reconciliation of book value per common share (GAAP) at period end to tangible book value per common share (non-GAAP) at period end.

FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES

Loans and Deposits

(Unaudited)


											% Change
(In millions, except %)	Jun 30, 2023		Mar 31, 2023		Dec 31, 2022		Sep 30, 2022		Jun 30, 2022		2Q23 vs 1Q23		2Q23 vs 2Q22

Loans held for investment:
Real Estate:
Commercial	$	8,813.9	$	8,680.8	$	8,528.6	$	8,026.9	$	7,857.7	1.5	%	12.2	%
Construction	1,836.5		1,893.0		1,944.4		2,023.0		1,759.5		(3.0)		4.4
Residential	2,198.3		2,191.1		2,188.3		2,127.7		2,060.4		0.3		6.7
Agricultural	755.7		769.7		794.9		800.9		821.5		(1.8)		(8.0)
Total real estate	13,604.4		13,534.6		13,456.2		12,978.5		12,499.1		0.5		8.8
Consumer:
Indirect	764.1		817.3		829.7		780.8		733.9		(6.5)		4.1
Direct	144.0		146.9		152.9		155.0		157.3		(2.0)		(8.5)
Credit card	72.1		71.5		75.9		74.2		74.8		0.8		(3.6)
Total consumer	980.2		1,035.7		1,058.5		1,010.0		966.0		(5.4)		1.5
Commercial	3,002.7		3,028.0		2,882.6		2,966.1		3,036.0		(0.8)		(1.1)
Agricultural	688.0		660.4		708.3		658.2		672.0		4.2		2.4
Other	1.7		1.6		9.2		3.8		—		6.3		100.0
Deferred loan fees and costs	(13.6)		(14.6)		(15.6)		(13.1)		(10.6)		(6.8)		28.3
Loans held for investment	$	18,263.4	$	18,245.7	$	18,099.2	$	17,603.5	$	17,162.5	0.1	%	6.4	%






Deposits:
Non-interest-bearing	$	6,518.2	$	6,861.1	$	7,560.0	$	8,163.3	$	8,295.4	(5.0)	%	(21.4)	%
Interest-bearing:
Demand	6,481.9		6,714.1		7,205.9		7,595.1		8,133.3		(3.5)		(20.3)
Savings	7,836.7		8,282.9		8,379.3		8,497.2		8,939.4		(5.4)		(12.3)
Time, $250 and over	657.9		526.5		438.0		319.3		272.1		25.0		141.8
Time, other	2,084.5		1,722.4		1,490.4		1,309.9		1,223.6		21.0		70.4
Total interest-bearing	17,061.0		17,245.9		17,513.6		17,721.5		18,568.4		(1.1)		(8.1)
Total deposits	$	23,579.2	$	24,107.0	$	25,073.6	$	25,884.8	$	26,863.8	(2.2)	%	(12.2)	%

Total core deposits (1)	$	22,921.3	$	23,580.5	$	24,635.6	$	25,565.5	$	26,591.7	(2.8)	%	(13.8)	%

(1) Core deposits are defined as total deposits less time deposits, $250 and over, and brokered deposits.

FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES

Credit Quality

(Unaudited)


																% Change
(In millions, except %)	Jun 30, 2023			Mar 31, 2023			Dec 31, 2022			Sep 30, 2022			Jun 30, 2022			2Q23 vs 1Q23		2Q23 vs 2Q22

Allowance for Credit Losses:
Allowance for credit losses	$	224.6		$	226.1		$	220.1		$	213.0		$	220.4		(0.7)	%	1.9	%
As a percentage of loans held for investment	1.23		%	1.24		%	1.22		%	1.21		%	1.28		%
As a percentage of non-accrual loans	260.86			279.83			371.79			268.26			205.98

Net loan charge-offs during quarter	$	11.4		$	6.2		$	1.1		$	12.0		$	0.3		83.9	%	NM
Annualized as a percentage of average loans	0.25		%	0.14		%	0.02		%	0.27		%	0.01		%

Non-Performing Assets:
Non-accrual loans	$	86.1		$	80.8		$	59.2		$	79.4		$	107.0		6.6	%	(19.5)	%
Accruing loans past due 90 days or more	6.7			4.5			6.4			6.6			2.9			48.9		131.0
Total non-performing loans	92.8			85.3			65.6			86.0			109.9			8.8		(15.6)
Other real estate owned	14.4			13.4			12.7			16.4			16.8			7.5		(14.3)
Total non-performing assets	$	107.2		$	98.7		$	78.3		$	102.4		$	126.7		8.6	%	(15.4)	%

Non-performing assets as a percentage of:
Loans held for investment and OREO	0.59		%	0.54		%	0.43		%	0.58		%	0.74		%
Total assets	0.35			0.31			0.24			0.33			0.40

Non-accrual loans to loans held for investment	0.47			0.44			0.33			0.45			0.62

Accruing Loans 30-89 Days Past Due	$	49.5		$	52.3		$	62.3		$	52.5		$	56.4		(5.4)	%	(12.2)	%


Criticized Loans:
Special Mention	$	221.9		$	243.8		$	290.4		$	273.7		$	275.9		(9.0)	%	(19.6)	%
Substandard	386.9			355.0			316.2			277.7			461.4			9.0		(16.1)
Doubtful	32.8			22.8			8.5			25.5			42.7			43.9		(23.2)
Total	$	641.6		$	621.6		$	615.1		$	576.9		$	780.0		3.2	%	(17.7)	%

NM - not meaningful

FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES

Selected Ratios - Annualized

(Unaudited)



	Jun 30, 2023				Mar 31, 2023			Dec 31, 2022			Sep 30, 2022			Jun 30, 2022
Annualized Financial Ratios (GAAP)
Return on average assets	0.86		%		0.71		%	1.07		%	1.07		%	0.79		%
Return on average common stockholders' equity	8.44				7.25			11.16			10.49			7.52
Yield on average earning assets	4.52				4.43			4.24			3.99			3.35
Cost of average interest-bearing liabilities	1.88				1.46			0.89			0.40			0.14
Interest rate spread	2.64				2.97			3.35			3.59			3.21
Net interest margin ratio	3.12				3.36			3.61			3.71			3.25
Efficiency ratio	60.95				63.38			57.07			58.37			71.37
Loans held for investment to deposit ratio	77.46				75.69			72.18			68.01			63.89

Annualized Financial Ratios - Operating** (Non-GAAP)
Tangible book value per common share	$	18.12			$	18.57		$	17.69		$	17.01		$	18.92
Tangible common stockholders' equity to tangible assets	6.40		%		6.37		%	5.95		%	5.90		%	6.61		%
Return on average tangible common stockholders' equity	13.69				11.87			18.67			16.93			11.78

Consolidated Capital Ratios
Total risk-based capital to total risk-weighted assets	12.90		%	*	12.63		%	12.48		%	12.50		%	13.16		%
Tier 1 risk-based capital to total risk-weighted assets	10.76			*	10.52			10.45			10.49			11.09
Tier 1 common capital to total risk-weighted assets	10.76			*	10.52			10.45			10.49			11.09
Leverage Ratio	7.99			*	7.72			7.75			7.67			7.72




*Preliminary estimate - may be subject to change. The regulatory capital ratios presented include the assumption of the transitional method as a result of legislation by the U.S. Congress to provide relief for the economy and financial institutions in the United States from the COVID‑19 pandemic. The referenced relief ends on December 31, 2024 which allows a total five-year phase-in of the impact of CECL on capital and relief over the next two years for the impact on the allowance for credit losses resulting from the COVID‑19 pandemic.
**Non-GAAP financial measures - see Non-GAAP Financial Measures included herein for a reconciliation of book value per common share to tangible book value per common share, return on average common stockholders’ equity (GAAP) to return on average tangible common stockholders’ equity, and tangible common stockholders’ equity to tangible assets (non-GAAP).


FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
Average Balance Sheets
(Unaudited)

	Three Months Ended
	June 30, 2023						March 31, 2023						June 30, 2022
(In millions, except %)	Average Balance		Interest(2)		Average Rate		Average Balance		Interest(2)		Average Rate		Average Balance		Interest(2)		Average Rate
Interest-earning assets:
Loans (1)	$	18,351.5	$	243.2	5.32	%	$	18,273.6	$	237.2	5.26	%	$	17,220.4	$	193.5	4.51	%
Investment securities
Taxable	9,139.2		66.1		2.90		9,983.4		72.2		2.93		10,129.4		49.1		1.94
Tax-exempt	192.9		1.0		2.08		225.4		1.1		1.98		248.6		1.4		2.26
Investment in FHLB and FRB stock	225.2		3.4		6.06		210.5		3.0		5.78		103.9		1.1		4.25
Interest-bearing deposits in banks	419.4		5.4		5.16		365.7		4.2		4.66		2,050.0		3.4		0.67
Federal funds sold	0.6		—		—		0.8		—		—		0.1		—		—
Total interest-earning assets	$	28,328.8	$	319.1	4.52	%	$	29,059.4	$	317.7	4.43	%	$	29,752.4	$	248.5	3.35	%
Non-interest-earning assets	2,958.8						2,951.5						2,858.9
Total assets	$	31,287.6					$	32,010.9					$	32,611.3
Interest-bearing liabilities:
Demand deposits	$	6,417.2	$	9.9	0.62	%	$	6,973.4	$	8.7	0.51	%	$	8,103.7	$	1.8	0.09	%
Savings deposits	7,951.3		28.4		1.43		8,406.9		22.8		1.10		9,461.7		1.6		0.07
Time deposits	2,517.1		15.3		2.44		2,055.3		8.8		1.74		1,555.4		0.9		0.23
Repurchase agreements	1,020.6		1.5		0.59		1,005.8		1.1		0.44		1,182.2		0.3		0.10
Other borrowed funds	2,966.4		39.3		5.31		2,615.2		31.2		4.84		—		—		—
Long-term debt	120.8		1.4		4.65		120.8		1.5		5.04		120.4		1.4		4.66
Subordinated debentures held by subsidiary trusts	163.1		3.1		7.62		163.1		2.9		7.21		163.1		1.4		3.44
Total interest-bearing liabilities	$	21,156.5	$	98.9	1.88	%	$	21,340.5	$	77.0	1.46	%	$	20,586.5	$	7.4	0.14	%
Non-interest-bearing deposits	6,521.9						7,064.9						8,288.0
Other non-interest-bearing liabilities	426.3						458.5						319.4
Stockholders’ equity	3,182.9						3,147.0						3,417.4
Total liabilities and stockholders’ equity	$	31,287.6					$	32,010.9					$	32,611.3
Net FTE interest income (non-GAAP)(3)			$	220.2					$	240.7					$	241.1
Less FTE adjustments (2)			(1.8)						(1.8)						(2.1)
Net interest income from consolidated statements of income			$	218.4					$	238.9					$	239.0
Interest rate spread					2.64	%					2.97	%					3.21	%
Net interest margin
Net FTE interest margin (non-GAAP)(3)					3.12						3.36						3.25
Cost of funds, including non-interest-bearing demand deposits (4)					1.43						1.10						0.10

(1) Average loan balances include loans held for sale and non-accrual loans. Interest income on loans includes amortization of deferred loan fees net of deferred loan costs of $0.9 million, $0.9 million, and $2.1 million at June 30, 2023, March 31, 2023, and June 30, 2022, respectively.
(2) Management believes fully taxable equivalent, or FTE, interest income is useful to investors in evaluating the Company’s performance as a comparison of the returns between a tax-free investment and a taxable alternative. The Company adjusts interest income and average rates for tax exempt loans and securities to a FTE basis utilizing a 21.00% and 26.25% tax rate for 2023 and 2022, respectively.
(3) Non-GAAP financial measure - see Non-GAAP Financial Measures included herein for a reconciliation to GAAP measures.
(4) Calculated by dividing total annualized interest on interest-bearing liabilities by the sum of total interest-bearing liabilities plus non-interest-bearing deposits.


FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
Non-GAAP Financial Measures
(Unaudited)

		As of or For the Quarter Ended
(In millions, except % and per share data)		Jun 30, 2023			Mar 31, 2023			Dec 31, 2022			Sep 30, 2022			Jun 30, 2022
Total common stockholders' equity (GAAP)	(A)	$	3,121.2		$	3,160.3		$	3,073.8		$	3,005.5		$	3,271.9
Less goodwill and other intangible assets (excluding mortgage servicing rights)		1,218.0			1,221.9			1,225.9			1,229.0			1,232.9
Tangible common stockholders' equity (Non-GAAP)	(B)	$	1,903.2		$	1,938.4		$	1,847.9		$	1,776.5		$	2,039.0

Total assets (GAAP)		$	30,976.3		$	31,637.7		$	32,287.8		$	31,344.7		$	32,061.8
Less goodwill and other intangible assets (excluding mortgage servicing rights)		1,218.0			1,221.9			1,225.9			1,229.0			1,232.9
Tangible assets (Non-GAAP)	(C)	$	29,758.3		$	30,415.8		$	31,061.9		$	30,115.7		$	30,828.9

Average Balances:
Total common stockholders' equity (GAAP)	(D)	$	3,182.9		$	3,147.0		$	3,050.1		$	3,239.7		$	3,417.4
Less goodwill and other intangible assets (excluding mortgage servicing rights)		1,219.8			1,223.8			1,226.9			1,230.9			1,235.1
Average tangible common stockholders' equity (Non-GAAP)	(E)	$	1,963.1		$	1,923.2		$	1,823.2		$	2,008.8		$	2,182.3

Net interest income		$	218.4		$	238.9		$	258.4		$	266.8		$	239.0
FTE interest income		1.8			1.8			2.3			2.1			2.1
Net FTE interest income	(F)	220.2			240.7			260.7			268.9			241.1
Less purchase accounting accretion		4.6			5.2			8.4			17.7			16.7

Adjusted net FTE interest income	(G)	$	215.6		$	235.5		$	252.3		$	251.2		$	224.4

Average interest-earning assets	(H)	$	28,328.8		$	29,059.4		$	28,680.9		$	28,731.2		$	29,752.4



Total quarterly average assets	(J)	31,287.6			32,010.9			31,716.0			31,653.7			32,611.3
Annualized net income available to common shareholders	(K)	268.7			228.3			340.4			340.0			257.1
Common shares outstanding	(L)	105,021			104,382			104,442			104,451			107,758

Return on average assets (GAAP)	(K) / (J)	0.86		%	0.71		%	1.07		%	1.07		%	0.79		%
Return on average common stockholders' equity (GAAP)	(K) / (D)	8.44			7.25			11.16			10.49			7.52
Average common stockholders' equity to average assets (GAAP)	(D) / (J)	10.17			9.83			9.62			10.23			10.48
Book value per common share (GAAP)	(A) / (L)	$	29.72		$	30.28		$	29.43		$	28.77		$	30.36
Tangible book value per common share (Non-GAAP)	(B) / (L)	18.12			18.57			17.69			17.01			18.92
Tangible common stockholders' equity to tangible assets (Non-GAAP)	(B) / (C)	6.40		%	6.37		%	5.95		%	5.90		%	6.61		%
Return on average tangible common stockholders' equity (Non-GAAP)	(K) / (E)	13.69			11.87			18.67			16.93			11.78
Net interest margin ratio (FTE) (Non-GAAP)	(F*) / (H)	3.12			3.36			3.61			3.71			3.25
Adjusted net interest margin ratio (FTE) (Non-GAAP)	(G*) / (H)	3.05			3.29			3.49			3.47			3.03

*Annualized

First Interstate BancSystem, Inc.

P.O. Box 30918 Billings, Montana 59116 (406) 255-5311

www.FIBK.com

2Q 2023 Investor Presentation Exhibit 99.2 July 26, 2023

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS This presentation contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, and Rule 175 promulgated thereunder, and Section 21E of the Securities Exchange Act of 1934, as amended, and Rule 3b-6 promulgated thereunder, that involve inherent risks and uncertainties. Any statements about our plans, objectives, expectations, strategies, beliefs, or future performance or events constitute forward-looking statements. Such statements are identified by words or phrases such as “believes,” “expects,” “anticipates,” “plans,” “trends,” “objectives,” “continues” or similar expressions, or future or conditional verbs such as “will,” “would,” “should,” “could,” “might,” “may” or similar expressions. Forward-looking statements involve known and unknown risks, uncertainties, assumptions, estimates and other important factors that could cause actual results to differ materially from any results, performance or events expressed or implied by such forward-looking statements. The following factors, among others, may cause actual results to differ materially from current expectations in the forward-looking statements, including those set forth in this presentation: new, or changes in, governmental regulations; tax legislative initiatives or assessments; more stringent capital requirements, to the extent they may become applicable to us; changes in accounting standards; any failure to comply with applicable laws and regulations, including, but not limited to, the CRA and fair lending laws, the USA PATRIOT ACT, OFAC guidelines and requirements, the BSA, and the related FinCEN and FFIEC Guidelines and regulations (as each of such terms and acronyms is defined below); lending risks and risks associated with loan sector concentrations; a decline in economic conditions that could reduce demand for our products and services and negatively impact the credit quality of loans; loan credit losses exceeding estimates; the soundness of other financial institutions; the ability to meet cash flow needs and availability of financing sources for working capital and other needs; a loss of deposits or a change in product mix that increases the Company’s funding costs; changes in interest rates; changes to United States trade policies, including the imposition of tariffs and retaliatory tariffs; competition from new or existing financial institutions and non-banks; variable interest rates tied to London Interbank Offered rate (LIBOR) that are no longer be available to us; exposure to losses in collateralized loan obligation securities; cyber-security risks, including “denial-of-service attacks,” “hacking,” and “identity theft” that could result in the disclosure of confidential information; privacy, information security, and data protection laws, rules, and regulations that affect or limit how we collect and use personal information; the potential impairment of our goodwill and other intangible assets; our reliance on other companies that provide key components of our business infrastructure; events that may tarnish our reputation; the loss of the services of key members of our management team and directors; our ability to attract and retain qualified employees to operate our business; costs associated with repossessed properties, including environmental remediation; the effectiveness of our systems of internal operating and accounting controls; our ability to implement technology-facilitated products and services or be successful in marketing these products and services to our clients; difficulties we may face in combining the operations of acquired entities or assets with our own operations or assessing the effectiveness of businesses in which we make strategic investments or with which we enter into strategic contractual relationships; incurrence of significant costs related to mergers and related integration activities; the volatility in the price and trading volume of our common stock; “anti- takeover” provisions and the regulations, which may make it more difficult for a third party to acquire control of us even in circumstances that could be deemed beneficial to stockholders; changes in our dividend policy or our ability to pay dividends; our common stock not being an insured deposit; the potential dilutive effect of future equity issuances; the subordination of our common stock to our existing and future indebtedness; the repercussions of the COVID-19 pandemic and the U.S., state and local government’s response to the pandemic; the effect of global conditions, earthquakes, volcanoes, tsunamis, floods, fires, drought, and other natural catastrophic events; and the impact of climate change and environmental sustainability matters. The foregoing factors are not necessarily all of the factors that could cause our actual results, performance or achievements to differ materially from those expressed in or implied by any of our forward-looking statements. Other unknown or unpredictable factors also could harm our results. All forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by the cautionary statements set forth above and included in our periodic reports filed with the Securities and Exchange Commission, or SEC, under the Securities Exchange Act of 1934, as amended, under the caption “Risk Factors”. Interested parties are urged to read in their entirety such risk factors prior to making any investment decision with respect to the Company. Forward-looking statements speak only as of the date they are made and we do not undertake or assume any obligation to update publicly any of these statements to reflect actual results, new information or future events, changes in assumptions or changes in other factors affecting forward- looking statements, except to the extent required by applicable laws. If we update one or more forward-looking statements, no inference should be drawn that we will make additional updates with respect to those or other forward-looking statements. 2

FIRST INTERSTATE BANCSYSTEM, INC. OVERVIEW Premier community banking franchise in growing markets throughout the Midwest and Pacific Northwest Financial Highlights Balance Sheet Capital Assets $31.0 Billion Total RBC3** 12.90% LHFI1 $18.3 Billion CET14** 10.76% Deposits $23.6 Billion Leverage** 7.99% ACL2/LHFI 1.23% TCE5 6.40% 1Loans held for investment (LHFI) 3Risk based capital (RBC) 2Allowance for credit losses (ACL) 4Common equity tier-1 (CET1) 5Tangible common equity (TCE) Corporate Overview Headquarters Billings, MT Exchange/Listing NASDAQ: FIBK Market Capitalization* $2.5 Billion Annualized Dividend Yield 7.5% Branch Network 307 banking offices Sub Debt Rating Kroll BBB 3 307 banking offices in 14 states * Calculated using closing stock price of $23.84 as of 6/30/2023 ** Preliminary estimates - may be subject to change

q Shareholder value creation is a top priority - building long-term value for all stakeholders, directly aligned with management compensation q Experienced leadership team q Diverse Board advising on strategy, overseeing risk and aligned with shareholders q Economically Diverse and Growing Footprint with 307 branches across 14 northwest and midwest states q Balance Sheet Strength - diverse loan portfolio, granular core funded deposit base, strong liquidity profile and strong capital position q Emphasis on risk management with a conservative credit strategy q Highly experienced bank acquirer - 8 successful acquisitions over the last 10 years FIBK INVESTMENT THESIS 4

SECOND QUARTER 2023 HIGHLIGHTS Earnings • Net income of $67.0 million, or $0.65 per share, included $0.01 of selected items in Q2 2023, mainly $1.9 million of severance • Net interest margin1 (NIM) of 3.12%, a decrease of 24 basis points from Q1 2023; adjusted NIM of 3.05%2, a decrease of 24 basis points from Q1 2023, primarily a result of the continued shift in the funding mix to higher-cost deposits and borrowings • Company remains committed to controlling expenses and completed the restructuring of our mortgage business, resulting in a net reduction to staff of 70 and an estimated annualized cost reduction of $6.9 million • Efficiency ratio of 61.0%; adjusted efficiency ratio of 60.7%2 Balance Sheet • Modest loan growth of $17.7 million, or 0.4% annualized, from 3/31, with growth in CRE largely offset by declines in construction and consumer balances • Total deposits declined $527.8 million or 2.2% from 3/31, as expected, but grew in the month of June with normal seasonality; the Company continued to have no brokered deposit balances • The Company’s balance sheet consistently maintains a strong liquidity position, with a Loan/deposit ratio of 77.5% at 6/30 Asset Quality • Overall, credit quality remains strong; Total criticized loans increased $20.0 million, or 3.2%, or just 3.5% of total loans HFI • Total non-performing loans of $92.8 million increased 8.8% from 3/31; reflecting 0.51% of LHFI, with an ACL coverage ratio of 242.0% at 6/30 • Net charge-offs (NCOs) were $11.4 million, or an annualized 25 basis points of average loans outstanding, of which approximately 85% is attributable to one metro office construction credit • While the total ACL increased modestly, there was a redistribution to the unfunded allowance from funded, which drove the decline to 1.23% of LHFI at 6/30 compared to 1.24% at 3/31 Capital • Paid a quarterly cash dividend of $0.47 per share, for an annualized yield of 7.5% in Q2 2023 • Exceeded all regulatory capital adequacy requirements; CET1 of 10.76%3 and total RBC of 12.90%3 at 6/30 5 1 Net interest margin is calculated using fully-taxable equivalent (FTE) net interest income 2 See non-GAAP table in appendix for reconciliation 3 Preliminary estimates - may be subject to change

SECOND QUARTER 2023 RESULTS Summary of Q2 2023 Results Dollars in millions, except per share data 2Q23 Net interest income $218.4 Provision for credit losses 11.7 Non-interest income 44.1 Non-interest expense 163.9 Income before taxes 86.9 Income taxes 19.9 Net income $67.0 Diluted earnings per share (EPS) $0.65 Q2 2023 Selected items impact Dollars in millions, except per share data Income Statement Geography Pre-tax (in MM) After-tax (in MM) Reported EPS Impact Severance Expense Salaries and Wages $(1.9) $(1.5) $(0.01) Investment securities loss (0.1) (0.1) — Totals $(2.0) $(1.6) $(0.01) 6 Notes: • Q2 2023 results include $3.0 million in additional provision for unfunded commitments, reported through the provision for loan losses

DIVERSIFIED LOAN PORTFOLIO Loans Held for Investment Commercial RE, 48% Construction RE, 10% Residential RE, 12% Agriculture RE, 4% Consumer, 5%Commercial, 17% Agriculture, 4% Loans by Geography MT, 15% WY, 5% ID, 5% WA, 8% OR, 9% SD, 10%ND, 2% NE, 6% IA, 10% KS, 2% AZ, 6% CO, 7% Other, 15% Revolving Commitments ($MM) $3.1 $3.2 $3.2 $3.2 $3.1 37.9% 37.1% 36.8% 37.1% 37.1% Unfunded Funded 2Q22 3Q22 4Q22 1Q23 2Q23 7 Loan Highlights: • Loan growth of $17.7 million in Q2, or 0.4% annualized • Non-revolving unfunded commitments of $1.6 billion at 6/30 • Commercial real estate (RE) commitments are 34.0% owner- occupied $18.3B Balances as of June 30, 2023

CRE OFFICE EXPOSURE 8 Highlights: • Totals include General Office exposure for all Non-Owner Occupied CRE and Construction loan products, which totals 4.0% of total loans at 6/30. Metro exposure totals <1.0% of total loans at 6/30 ◦ Metro Office Construction totals 2 deals for $24.7 million • $325.0 million of Total CRE exposure with current yields under 5.25% will mature within the next 12 months, with <$16.5 million being CRE Office Balances as of June 30, 2023 1Metro is defined as Seattle, Portland, Phoenix, Minneapolis, Denver and Kansas City Loan Balance ($MM) < $5MM $5MM - $10MM $10MM - $20MM >= $20MM Grand Total Metro1 $37.3 $28.0 $24.7 $46.7 $136.8 Mid-Metro $16.8 $18.0 $23.5 $58.3 Non-Metro $265.7 $71.0 $133.4 $68.7 $538.8 Grand Total $319.8 $117.1 $181.6 $115.4 $733.9 Loan Count < $5MM $5MM - $10MM $10MM - $20MM >= $20MM Grand Total Metro1 16 4 2 2 24 Mid-Metro 15 3 2 20 Non-Metro 279 10 9 2 300 Grand Total 310 17 13 4 344

Deposits by State MT, 24% WY, 12% ID, 7% WA, 3% OR, 11% SD, 16% NE, 9% IA, 10% MO, 1% AZ, 3% CO, 4% Mix of Consumer and Business Deposits 49% 51% 52% 54% 53% 51% 49% 48% 46% 47% Total Consumer Deposits Total Business Deposits 2Q22 3Q22 4Q22 1Q23 2Q23 9 Deposit Highlights: • As expected, total deposits declined $527.8 million, or 2.2% during Q2 • Deposit balances increased by $375 million, or 1.6% in the month of June. Growth came late in the month, in line with historical seasonality • Deposit mix trending as expected, with a shift in the mix out of non- interest bearing into time balances. Expecting further migration of non-interest bearing to end the year around 25% • Cumulative cycle-to-date interest bearing deposit beta1 of 24% through June 30 Average Deposit Balances 30% 30% 29% 28% 27% 35% 33% 33% 34% 34% 6% 6% 7% 8% 11% 30% 31% 31% 29% 28% 0.06% 0.20% 0.44% 0.68% 0.91% Demand Savings Time Non-interest bearing Total Cost of Deposits 2Q22 3Q22 4Q22 1Q23 2Q23 DIVERSE DEPOSIT BASE: BY TYPE OF ACCOUNT Balances as of June 30, 2023 1Deposit beta measures the sensitivity of the bank’s deposit cost to changes in short-term interest rates

DIVERSE DEPOSIT BASE: CHANGES IN ACCOUNT BALANCES Deposit Changes by Account Balance ($MM) $0.6 $4.3 $2.9 $4.8 $3.3 $2.4 $3.8 $1.1 $1.0 $0.8 $0.6 $4.4 $2.9 $4.9 $3.0 $2.0 $3.0 $1.1 $0.9 $0.7 12/31/22 6/30/23 < $ 5K $5 K - $ 50 K $5 0K - $ 10 0K $1 00 K - $ 25 0K $2 50 K - $ 50 0K $5 00 K - $ 1M $1 M - $ 5M $5 M - $ 10 M $1 0M - $ 25 M > $ 25 M 10 Commercial Customer Deposit Balance Distribution < $ 5K $5 K - $ 50 K $5 0K - $ 10 0K $1 00 K - $ 25 0K $2 50 K - $ 50 0K $5 00 K - $ 1M $1 M - $ 5M $5 M - $ 10 M $1 0M - $ 25 M > $ 25 M 0% 10% 20% 30% Consumer Customer Deposit Balance Distribution < $ 5K $5 K - $ 50 K $5 0K - $ 10 0K $1 00 K - $ 25 0K $2 50 K - $ 50 0K $5 00 K - $ 1M $1 M - $ 5M $5 M - $ 10 M $1 0M - $ 25 M > $ 25 M 0% 10% 20% 30% 40% Deposit Highlights: • Average consumer account balances less than $20,000, with 76% less than $250K • Average business account balances approximately $90,000, with 54% less than $1M *Line items may not sum due to rounding

11 Uninsured vs Insured Deposit Mix 69% 70% 69% 72% 72% 31% 30% 31% 28% 28% Insured Deposits Uninsured Deposits¹ 2Q22 3Q22 4Q22 1Q23 2Q23 Deposit Highlights: • Insured deposits stable during period and are approximately $15.8 billion at 6/30 • Uninsured deposits not subject to collateralization are approximately $6.2 billion at 6/30. The Company continues to have zero brokered deposit funds at 6/30 • Immediate liquidity of approximately $10.3 billion at 6/30, or 1.7x uninsured deposit balances not subject to collateralization DIVERSE DEPOSIT BASE: UNINSURED VS INSURED MIX 1 Net of fully collateralized deposit balances

Total Risk-Based Capital Ratios 13.16% 12.50% 12.48% 12.63% 12.90% 11.09% 10.49% 10.45% 10.52% 10.76% 2.07% 2.01% 2.03% 2.11% 2.14% CET1 Total RBC 2Q22 3Q22 4Q22 1Q23 2Q23² CAPITAL AND LIQUIDITY Liquid and flexible balance sheet with strong capital position Common Equity (CE) and Tangible Common Equity¹ $30.36 $28.77 $29.43 $30.28 $29.72 $18.92 $17.01 $17.69 $18.57 $18.12 6.61% 5.90% 5.95% 6.37% 6.40% 10.20% 9.59% 9.52% 9.99% 10.08% TBVPS BVPS TCE Ratio CE Ratio 2Q22 3Q22 4Q22 1Q23 2Q23 12 LHFI to Deposit Ratio 63.9% 68.0% 72.2% 75.7% 77.5% 2Q22 3Q22 4Q22 1Q23 2Q23 Capital and Liquidity Highlights: • Annualized dividend yield of 7.5% based on Q2 average share price of $25.21 • TBVPS and TCE ratio declined during the quarter, as retained earnings were offset by accumulated other comprehensive income (AOCI). Q2 AOCI mark is equal to $4.37 of TBVPS • All capital ratios exceeded regulatory requirements 1 See Non-GAAP table in appendix for reconciliation 2 Preliminary estimates - may be subject to change

ALLOWANCE FOR CREDIT LOSSES ACL ($MM) and Funded ACL/LHFI Ratio $226.6 $222.7 $236.3 $243.9 $245.4 $220.4 $213.0 $220.1 $226.1 $224.6 $6.2 $9.7 $16.2 $17.8 $20.8 1.28% 1.21% 1.22% 1.24% 1.23% Funded ACL Unfunded ACL Funded ACL % of LHFI 2Q22 3Q22 4Q22 1Q23 2Q23 13 ACL Highlights: • The Company migrated to a new CECL model during the second quarter of 2023, resulting in the redistribution of a portion of the total ACL from funded to unfunded • ACL coverage ratio to non-performing loans (NPLs) remains strong at 242.0% as of Q2 ACL Roll-forward ($MM) Funded Unfunded Investments Total ACL 3/31/23 $226.1 $17.8 $3.3 $247.2 ACL Provision (Reversal) 9.9 3.0 (1.2) 11.7 Net Charge-offs 11.4 — — 11.4 ACL 6/30/23 $224.6 $20.8 $2.1 $247.5 * Line items may not sum due to rounding

ASSET QUALITY AND RESERVE TRENDS Net Charge-offs ($MM) and Net Charge-Offs Ratio $0.3 $12.0 $1.1 $6.2 $11.4 0.01% 0.27% 0.02% 0.14% 0.25% Net Charge-offs % of Average Loans 2Q22 3Q22 4Q22 1Q23 2Q23 Credit management resulted in stable asset quality Total NPLs ($MM) and ACL/NPL Ratios $109.9 $86.0 $65.6 $85.3 $92.8 200.5% 247.7% 335.5% 265.1% 242.0% NPLs ACL / NPL Ratio 2Q22 3Q22 4Q22 1Q23 2Q23 Total Criticized Loans ($MM) and Criticized Loan Ratio $780.0 $576.9 $615.1 $621.6 $641.6 4.5% 3.3% 3.4% 3.4% 3.5% Criticized Loans % of Total Loans 2Q22 3Q22 4Q22 1Q23 2Q23 14 Asset Quality Highlights: • Total non-performing loans at 6/30 increased by $7.5 million, or 8.8% from 3/31 • Approximately 85% of Q2 2023 NCOs are attributable to one metro office construction project

NET INTEREST INCOME (NII) Net Interest Income¹ ($MM) and Net Interest Margin¹ $241.1 $268.9 $260.7 $240.7 $220.2 $224.4 $251.2 $252.3 $235.5 $215.6 $16.7 $17.7 $8.4 $5.2 $4.6 3.25% 3.71% 3.61% 3.36% 3.12% 3.03% 3.47% 3.49% 3.29% 3.05% Adjusted NII ² Loan PAA Net Interest Margin Adjusted NIM ² 2Q22 3Q22 4Q22 1Q23 2Q23 15 Net Interest Income and Net Interest Margin Highlights: • $4.6 million total loan purchase accounting accretion (PAA) in Q2 2023, a decrease from $5.2 million in the prior quarter • Total remaining PAA of $74.9 million at 6/30 ◦ Scheduled accretion of $8.6 million/$16.4 million/$13.9 million for the remainder of FY23/FY24/FY25 • Q2 2023 NIM declined by 24 basis points, with the contribution from PAA remaining unchanged compared with the prior quarter • Excluding the impact from PAA, the Q2 2023 adjusted NIM2 declined by 24 basis points, primarily driven by a continued shift in mix of interest-bearing liabilities toward short-term borrowings, while increased interest-bearing deposit costs outpaced ex-PAA loan yield expansion. 1 Reported on a fully-taxable equivalent (“FTE”) basis 2 See Non-GAAP table in appendix for reconciliation

NET INTEREST INCOME (cont’d) 16 NIM Waterfall Analysis 3.36 0.03 (0.01) 0.01 (0.18) (0.01) (0.05) 0.02 0.03 (0.04) (0.04) 3.12 1Q 23 Lo an s Inv es tm en ts Cash Dep osi ts Re po s Bo rro wing s Lo an s Inv es tm en ts Dep osi ts Bo rro wing s 2Q 23 RATE IMPACT MIX IMPACT

LOAN PORTFOLIO RE-PRICING PROFILE Contractual Maturity/Re-pricing Buckets¹ ($B) $4.3 $3.4 $4.9 $2.8 $2.8 7.61% 4.81% 4.38% 4.61% 4.24% 1 M 2 - 12 M 1 - 3 Yr 3 - 5 Yr > 5 Yr $— $1.0 $2.0 $3.0 $4.0 $5.0 $6.0 17 Loan Re-pricing Characteristics Fixed, 60% Variable, 11% Libor 1M, 7% SOFR 1M, 3% Adjustable excl Libor 1M & SOFR 1M, 19% 1 Contractual re-pricing benchmarks with Roll-off Coupon *Line items may not sum due to rounding

INVESTMENT PORTFOLIO 18 Total Portfolio Duration at Quarter End 3.9 3.9 3.7 3.8 3.7 2Q22 3Q22 4Q22 1Q23 2Q23 (in years) Projected Cash Flow ($MM) & Yield Roll-Off at Quarter-end $188.9 $168.1 $465.4 $166.5 $180.4 $207.8 2.32% 2.28% 2.23% 2.32% 2.41% 2.59% 3Q23E 4Q23E 1Q24E 2Q24E 3Q24E 4Q24E

19 Non-interest Income by Type ² Payment Services, 45% Mortgage Banking, 6% Wealth Management, 20% Deposit Service Charges, 13% Other Service Charges & Fees, 5% Other Income, 11% Dollars in millions 2Q22 1Q23 2Q23 Payment services revenues $ 19.5 $ 18.7 $ 20.1 Mortgage banking revenues 5.0 2.3 2.6 Wealth management revenues 9.3 9.0 8.8 Service charges on deposit accounts 6.3 5.2 5.8 Other service charges, commissions and fees 3.6 2.4 2.4 Investment securities losses, net (0.1) (23.4) (0.1) Other income 6.3 2.2 4.5 Total Reported Non-interest Revenue $ 49.9 $ 16.4 $ 44.1 % of Total Revenue 17.3 % 6.4 % 16.8 % Selected Items: Investment securities losses, net (0.1) (23.4) (0.1) Other income 1.7 — — Adj. Non-interest Revenue1 $ 48.3 $ 39.8 $ 44.2 NON-INTEREST INCOME 1 See Non-GAAP table in appendix for reconciliation 2 Excludes investment security loss; may not sum due to rounding

NON-INTEREST EXPENSE 20 Dollars in millions 2Q22 1Q23 2Q23 Salaries and wages $ 74.8 $ 65.6 $ 68.1 Employee benefits 19.4 22.8 19.3 Occupancy and equipment 17.0 18.4 17.3 Other intangible amortization 4.1 4.0 3.9 Other expenses 49.2 54.8 54.7 Other real estate owned expense — 0.2 0.6 Acquisition related expenses 45.8 — — Total Reported Non-interest Expense $ 210.3 $ 165.8 $ 163.9 Selected Items: Acquisition related expenses 45.8 — — Adj. Non-interest Expense2 $ 164.5 $ 165.8 $ 163.9 Non-interest Expense ($MM) and Efficiency Ratio 210.3 173.2 175.3 165.8 163.9164.5 168.7 170.1 165.8 163.9 71.4% 58.4% 57.1% 63.4% 61.0% 55.8% 52.4% 54.6% 58.0% 60.7% Total Non-interest Expenses Adjusted Non-interest Expenses ² Efficiency Ratio ¹ Adjusted Efficiency Ratio ² 2Q22 3Q22 4Q22 1Q23 2Q23 1 The ratio of the bank’s non-interest expense to revenue (per FDIC definition) 2 See Non-GAAP table in appendix for reconciliation Non-interest Expense Notes: • Q2 2023 results include $1.9 million in severance expense in salaries and wages

Balance Sheet • Loan growth expected to be low-single-digit end-of-period growth for full year • Securities cash flow and yield roll-off according to the graphic on slide 18 • Average earning assets will be modestly below $28 billion for the remainder of the year • Deposits assumed relatively stable through year-end Net Interest Income & Net Interest Margin • Ex-PAA, full-year NII down low-single-digits; assumes cumulative IB deposit beta by year-end ‘23 in low-to-mid 30s • NIM pressure expected to lessen in second half of the year relative to the first. For the balance of the year, adj. NIM, excluding PAA, is expected to modestly decline from the Q2 average. • Total PAA should approximate $8.6 million for the rest of the year, as detailed on slide 15 Fees and Expenses • Quarterly fee income for the remainder of 2023 is expected to be up low-to-mid single digits from reported Q2 2023 levels • Total operating expenses with an anticipated increase of 1 - 2% from a base of $647.1 million in 2022, excluding impact from FDIC special assessment Other • Effective tax rate anticipated to be ~23.5% for full-year 2023 2023 GUIDANCE SUMMARY 21 Preliminary estimates - may be subject to change

NON-GAAP FINANCIAL MEASURES 22 In addition to results presented in accordance with accounting principles generally accepted in the United States of America, or GAAP, this press release contains the following non-GAAP financial measures that management uses to evaluate our performance relative to our capital adequacy standards: (i) tangible common stockholders’ equity; (ii) tangible assets; (iii) tangible book value per common share; (iv) tangible common stockholders’ equity to tangible assets; (v) adjusted net interest margin; (vi) adjusted efficiency ratio; and (vii) adjusted return on average equity. Tangible common stockholders’ equity is calculated as total common stockholders’ equity less goodwill and other intangible assets (excluding mortgage servicing rights). Tangible assets are calculated as total assets less goodwill and other intangible assets (excluding mortgage servicing rights). Tangible book value per common share is calculated as tangible common stockholders’ equity divided by common shares outstanding. Tangible common stockholders’ equity to tangible assets is calculated as tangible common stockholders’ equity divided by tangible assets. Adjusted net interest margin is calculated as adjusted net interest income divided by adjusted average earning assets (as such non-gaap financial measures are calculated on the reconciliation pages below). Adjusted efficiency ratio is calculated as adjusted expense for efficiency ratio divided by adjusted revenue (as such non-gaap financial measures are calculated on the reconciliation pages below). Adjusted return on average assets is calculated as adjusted net income (as calculated on the reconciliation pages below) divided by average stockholders’ equity. These non-GAAP financial measures may not be comparable to similarly titled measures reported by other companies because other companies may not calculate these non-GAAP measures in the same manner. They also should not be considered in isolation or as a substitute for measures prepared in accordance with GAAP. The Company adjusts the foregoing capital adequacy measures to exclude goodwill and other intangible assets (except mortgage servicing rights), adjusts its non-interest expense to exclude acquisition related expenses and litigation accrual (recovery), adjusts its net interest income to include non-interest income and exclude net gains or losses from investment securities, mortgage servicing rights impairments and recoveries, and other income, adjusts its net interest margin (FTE) to exclude purchase accounting accretion, and adjusts net income to include non-PCD CECL day two provision expense, acquisition related expenses, mortgage servicing rights fair value adjustments, other income items, investment security gains and losses, and other expense items. Management believes these non-GAAP financial measures, which are intended to complement the capital ratios defined by banking regulators and to present on a consistent basis our and our acquired companies’ organic continuing operations without regard to the acquisition costs and adjustments that we consider to be unpredictable and dependent on a significant number of factors that are outside our control, are useful to investors in evaluating the Company’s performance because, as a general matter, they either do not represent an actual cash expense and are inconsistent in amount and frequency depending upon the timing and size of our acquisitions (including the size, complexity and/or volume of past acquisitions, which may drive the magnitude of acquisition related costs, but may not be indicative of the size, complexity and/or volume of future acquisitions or related costs), or they cannot be anticipated or estimated in a particular period (in particular as it relates to unexpected recovery amounts). This impacts the ratios that are important to analysts and allows investors to compare certain aspects of the Company’s capitalization to other companies. See the Non-GAAP Financial Measures tables included below and the textual discussion for a reconciliation of the above described non-GAAP financial measures to their most directly comparable GAAP financial measures.

2Q22 3Q22 4Q22 1Q23 2Q23 (Dollars in millions) Total common stockholders' equity (GAAP) (A) $ 3,271.9 $ 3,005.5 $ 3,073.8 $ 3,160.3 $ 3,121.2 Less goodwill and other intangible assets (excluding mortgage servicing rights) 1,232.9 1,229.0 1,225.9 1,221.9 1,218.0 Tangible common stockholders' equity (Non-GAAP) (B) $ 2,039.0 $ 1,776.5 $ 1,847.9 $ 1,938.4 $ 1,903.2 Total assets (GAAP) $ 32,061.8 $ 31,344.7 $ 32,287.8 $ 31,637.7 $ 30,976.3 Less goodwill and other intangible assets (excluding mortgage servicing rights) 1,232.9 1,229.0 1,225.9 1,221.9 1,218.0 Tangible assets (Non-GAAP) (C) $ 30,828.9 $ 30,115.7 $ 31,061.9 $ 30,415.8 $ 29,758.3 Common shares outstanding (L) 107,758 104,451 104,442 104,382 105,021 Book value per common share (GAAP) (A) / (L) $ 30.36 $ 28.77 $ 29.43 $ 30.28 $ 29.72 Tangible book value per common share (Non-GAAP) (B) / (L) 18.92 17.01 17.69 18.57 18.12 Tangible common stockholders' equity to tangible assets (Non-GAAP) (B) / (C) 6.61 % 5.90 % 5.95 % 6.37 % 6.40 % NON-GAAP RECONCILIATION 23 * Line items may not sum due to rounding

2Q22 3Q22 4Q22 1Q23 2Q23 (Dollars in millions) Total non-interest expense $ 210.3 $ 173.2 $ 175.3 $ 165.8 $ 163.9 Less: Acquisition-related expense 45.8 4.0 3.9 — — Less: Litigation accrual — 0.5 1.3 — — Adjusted non-interest expense $ 164.5 $ 168.7 $ 170.1 $ 165.8 $ 163.9 Less: Intangible amortization 4.1 4.1 4.1 4.0 3.9 Less: Other real estate owned expense — — 2.2 0.2 0.6 Adjusted expense for efficiency ratio (A) $ 160.4 $ 164.6 $ 163.8 $ 161.6 $ 159.4 Net interest income $ 239.0 $ 266.8 $ 258.4 $ 238.9 $ 218.4 Add: Total non-interest income 49.9 22.9 41.6 16.4 44.1 Less: Net gain (loss) from investment securities (0.1) (24.2) — (23.4) (0.1) Less: Other income 1.7 — — — — Adjusted revenue (B) $ 287.3 $ 313.9 $ 300.0 $ 278.7 $ 262.6 Adjusted Efficiency Ratio (A)/(B) 55.83 % 52.44 % 54.60 % 57.98 % 60.70 % NON-GAAP RECONCILIATION 24 * Line items may not sum due to rounding

2Q22 3Q22 4Q22 1Q23 2Q23 (Dollars in millions) Net interest income on a fully-taxable equivalent ("FTE") basis (A) $ 241.1 $ 268.9 $ 260.7 $ 240.7 $ 220.2 Less purchase accounting accretion 16.7 17.7 8.4 5.2 4.6 Adjusted net interest income (B) $ 224.4 $ 251.2 $ 252.3 $ 235.5 $ 215.6 Average interest-earning assets (C) $ 29,752.4 $ 28,731.2 $ 28,680.9 $ 29,059.4 $ 28,328.8 Net interest margin (FTE), as reported (A annualized)/(C) 3.25 % 3.71 % 3.61 % 3.36 % 3.12 % Adjusted net interest margin (FTE) (B annualized)/(C) 3.03 % 3.47 % 3.49 % 3.29 % 3.05 % NON-GAAP RECONCILIATION 25 * Line items may not sum due to rounding

2Q22 3Q22 4Q22 1Q23 2Q23 (Dollars in millions); all adjustments are after-tax Net income (A) $ 64.1 $ 85.7 $ 85.8 $ 56.3 $ 67.0 Plus: Acquisition-related expenses 36.6 3.2 3.0 — — Plus: Other income items (1.4) — — — — Plus: Investment securities loss 0.1 19.2 — 17.7 0.1 Plus: Litigation accrual — 0.4 1.0 — — Adjusted net income (B) $ 99.4 $ 108.5 $ 89.8 $ 74.0 $ 67.1 Average stockholders' equity (C) $ 3,417.4 $ 3,239.7 $ 3,050.1 $ 3,147.0 $ 3,182.9 Return on average equity (A annualized)/(C) 7.52 % 10.49 % 11.16 % 7.25 % 8.44 % Adjusted return on average equity (B annualized)/(C) 11.67 % 13.29 % 11.68 % 9.54 % 8.46 % NON-GAAP RECONCILIATION 26 * Line items may not sum due to rounding

Cover	Jul. 26, 2023
Cover [Abstract]
Document Type	8-K
Document Period End Date	Jul. 26, 2023
Entity Registrant Name	FIRST INTERSTATE BANCSYSTEM, INC.
Entity Incorporation, State or Country Code	DE
Entity File Number	001-34653
Entity Tax Identification Number	81-0331430
Entity Address, Address Line One	401 North 31st Street
Entity Address, City or Town	Billings,
Entity Address, State or Province	MT
Entity Address, Postal Zip Code	59101
City Area Code	(406)
Local Phone Number	255-5311
Written Communications	false
Soliciting Material	false
Pre-commencement Tender Offer	false
Pre-commencement Issuer Tender Offer	false
Title of 12(b) Security	Class A common stock, $0.00001 par value
Trading Symbol	FIBK
Security Exchange Name	NASDAQ
Amendment Flag	false
Entity Central Index Key	0000860413
Entity Emerging Growth Company	false