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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
___________________________________________________________________________________________________________________________________________________ 
FORM 10-Q
_____________________________________________________________________________________________________________________________________________________ 

    Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
For the quarterly period ended September 30, 2022
OR
     Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
For the transition period from                   to                   
COMMISSION FILE NUMBER 001-34653
________________________________________________________________________________________________________ 
FIRST INTERSTATE BANCSYSTEM, INC.
(Exact name of registrant as specified in its charter)
________________________________________________________________________________________________________ 
Montana81-0331430
(State or other jurisdiction of
incorporation or organization)
(IRS Employer
Identification No.)
401 North 31st Street
Billings,MT59116-0918
(Address of principal executive offices)(Zip Code)
Registrant’s telephone number, including area code: (406) 255-5311
_________________________________________________________________________________________________ 

Securities registered pursuant to Section 12(b) of the Act:
Title of each classTrading Symbol(s)Name of each exchange on which registered
Class A common stock, no par valueFIBKNASDAQ
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.     Yes      No  
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files.)     Yes      No  
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Large accelerated filer  Accelerated filer
Non-accelerated filerSmaller reporting company
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.
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).  Yes   No  
Indicate the number of shares outstanding of each of the registrant’s classes of common stock, as of the latest practicable date:
October 31, 2022 – Class A common stock104,447,711 



Quarterly Report on Form 10-Q
FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
Index
September 30, 2022
  Page Nos.
Item 1.
Item 2.
Item 3.
Item 4.
Item 1.
Item 1A.
Item 2.
Item 3.
Item 4.
Item 5.
Item 6.



















2

FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
CONSOLIDATED BALANCE SHEETS
(In millions, except share data)
(Unaudited)
September 30,
2022
December 31,
2021
Assets
Cash and due from banks$390.4 $168.6 
Interest bearing deposits in banks201.4 2,176.1 
Federal funds sold0.1 0.1 
Total cash and cash equivalents591.9 2,344.8 
Investment securities:
Available-for-sale, at estimated fair value6,783.4 4,820.5 
Held-to-maturity, net of allowance for credit losses of $1.9 and $0 at September 30, 2022 and December 31, 2021 (estimated fair values of $3,063.5 and $1,667.5 at September 30, 2022 and December 31, 2021)
3,485.7 1,687.6 
Total investment securities10,269.1 6,508.1 
Federal Home Loan Bank and Federal Reserve Bank stock, at cost131.9 53.8 
Loans held for sale93.6 30.1 
Loans held for investment, net of deferred fees and costs17,603.5 9,331.7 
Allowance for credit losses213.0 122.3 
Net loans held for investment17,390.5 9,209.4 
Goodwill1,100.0 621.6 
Company-owned life insurance495.6 301.5 
Premises and equipment, net of accumulated depreciation445.4 299.6 
Other intangibles, net of accumulated amortization101.0 41.3 
Accrued interest receivable106.4 47.4 
Mortgage servicing rights, net of accumulated amortization and impairment reserve31.8 28.2 
Other real estate owned16.4 2.0 
Deferred tax asset, net223.8  
Other assets347.3 184.1 
Total assets$31,344.7 $19,671.9 
Liabilities and Stockholders’ Equity
Deposits:
Non-interest bearing$8,163.3 $5,568.3 
Interest bearing17,721.5 10,701.3 
Total deposits25,884.8 16,269.6 
Securities sold under repurchase agreements1,075.6 1,051.1 
Accounts payable and accrued expenses452.9 148.4 
Accrued interest payable7.4 3.7 
Deferred tax liability, net 9.3 
Long-term debt120.7 112.4 
Other borrowed funds625.0  
Allowance for credit losses on off-balance sheet credit exposures9.7 3.8 
Subordinated debentures held by subsidiary trusts163.1 87.0 
Total liabilities28,339.2 17,685.3 
Stockholders’ equity:
Preferred stock, no par value; 100,000 shares authorized; none issued and outstanding
  
Common stock, no par value; 150,000,000 and 100,000,000 shares authorized at September 30, 2022 and December 31, 2021; 104,450,804 shares and 62,200,456 shares issued and outstanding, respectively
2,477.4 945.0 
Retained earnings1,035.8 1,052.6 
Accumulated other comprehensive loss, net(507.7)(11.0)
Total stockholders’ equity3,005.5 1,986.6 
Total liabilities and stockholders’ equity$31,344.7 $19,671.9 
See accompanying notes to unaudited consolidated financial statements.
3

FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
CONSOLIDATED STATEMENTS OF INCOME
(In millions, except per share data)
(Unaudited)
 Three Months Ended September 30,Nine Months Ended September 30,
 2022202120222021
Interest income:
Interest and fees on loans$218.3 $111.9 $561.7 $325.1 
Interest and dividends on investment securities:
Taxable64.3 17.1 142.4 48.7 
Exempt from federal taxes1.4 1.4 4.1 4.2 
Interest and dividends on FHLB and FRB stock1.3 0.2 2.8 0.2 
Interest on deposits in banks1.4 0.7 6.5 1.7 
Total interest income286.7 131.3 717.5 379.9 
Interest expense:
Interest on deposits13.3 1.9 20.6 6.4 
Interest on securities sold under repurchase agreements0.8 0.1 1.4 0.3 
Interest on other borrowed funds2.4  2.4  
Interest on long-term debt1.5 1.5 4.6 4.5 
Interest on subordinated debentures held by subsidiary trusts1.9 0.7 4.3 2.1 
Total interest expense19.9 4.2 33.3 13.3 
Net interest income266.8 127.1 684.2 366.6 
Provision for (reversal of) credit losses8.4  68.0 (5.1)
Net interest income after provision for (reversal of) credit losses258.4 127.1 616.2 371.7 
Non-interest income:
Payment services revenues20.4 12.2 54.7 33.8 
Mortgage banking revenues2.7 11.6 16.1 32.8 
Wealth management revenues8.5 6.5 25.9 19.1 
Service charges on deposit accounts5.7 4.4 19.7 12.1 
Other service charges, commissions, and fees4.7 1.4 12.6 5.1 
Investment securities losses, net(24.2)0.3 (24.4)0.2 
Other income5.1 3.1 17.0 9.8 
Total non-interest income22.9 39.5 121.6 112.9 
Non-interest expense:
Salaries and wages71.9 42.0 206.7 122.6 
Employee benefits19.6 12.9 60.2 43.7 
Outsourced technology services15.9 8.2 40.0 24.7 
Occupancy, net11.3 7.3 32.5 21.7 
Furniture and equipment5.8 4.5 17.0 13.0 
OREO expense, net of income  0.1 (0.1)
Professional fees5.1 2.7 14.5 9.3 
FDIC insurance premiums4.1 1.7 10.2 4.8 
Other intangibles amortization4.1 2.4 11.8 7.4 
Other expenses31.4 17.6 82.7 49.6 
Acquisition related expenses4.0 6.6 115.0 6.6 
Total non-interest expense173.2 105.9 590.7 303.3 
Income before income tax108.1 60.7 147.1 181.3 
Provision for income tax22.4 13.6 30.7 40.3 
Net income$85.7 $47.1 $116.4 $141.0 
Earnings per common share (Basic)$0.80 $0.76 $1.13 $2.29 
Earnings per common share (Diluted)$0.80 $0.76 $1.13 $2.28 
Weighted average common shares outstanding (Basic)106,525,974 61,673,656 102,879,422 61,641,342 
Weighted average common shares outstanding (Diluted)106,589,699 61,747,972 102,935,360 61,732,822 
See accompanying notes to unaudited consolidated financial statements.
4

FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME
(In millions)
(Unaudited)
 Three Months Ended September 30,Nine Months Ended September 30,
 2022202120222021
Net income$85.7 $47.1 $116.4 $141.0 
Other comprehensive loss, before tax:
Investment securities available-for sale:
Change in net unrealized loss during period(236.4)(13.4)(650.6)(81.0)
Reclassification adjustment for net loss (gain) included in income24.2 (0.3)24.4 (0.2)
Reclassification adjustment for securities transferred from held-to-maturity to available-for-sale  0.2  
Net change in unamortized (losses) gains on available-for-sale securities transferred into held-to-maturity(1.7)(2.5)(25.6)22.3 
Change in unrealized (gain) loss on derivatives(15.9)3.2 (9.6)2.3 
Other comprehensive loss, before tax(229.8)(13.0)(661.2)(56.6)
Deferred tax benefit related to other comprehensive loss51.9 3.2 164.5 14.3 
Other comprehensive loss, net of tax(177.9)(9.8)(496.7)(42.3)
Comprehensive (loss) income, net of tax$(92.2)$37.3 $(380.3)$98.7 
See accompanying notes to unaudited consolidated financial statements.

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FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS’ EQUITY
(In millions, except share and per share data)
(Unaudited)
Three Months Ended September 30,
Common
stock
Retained
earnings
Accumulated
other
comprehensive
income (loss)
Total
stockholders’
equity
Balance at June 30, 2022$2,607.9 $993.8 $(329.8)$3,271.9 
Net income 85.7  85.7 
Other comprehensive loss, net of tax expense  (177.9)(177.9)
Common stock transactions:
3,280,042 common shares purchased and retired
(133.0)  (133.0)
251 non-vested common shares issued
    
27,443 non-vested common shares forfeited or canceled
    
Stock-based compensation expense2.5   2.5 
Common stock cash dividends declared ($0.41 per share)
 (43.7) (43.7)
Balance at September 30, 2022$2,477.4 $1,035.8 $(507.7)$3,005.5 
Common
stock
Retained
earnings
Accumulated
other
comprehensive
income (loss)
Total
stockholders’
equity
Balance at June 30, 2021$941.6 $1,005.2 $24.1 $1,970.9 
Net income 47.1  47.1 
Other comprehensive loss, net of tax expense  (9.8)(9.8)
Common stock transactions:
574 common shares purchased and retired
    
1,782 common shares issued
    
12,620 non-vested common shares issued
    
2,324 non-vested common shares forfeited or canceled
    
Stock-based compensation expense2.0   2.0 
Common stock cash dividends declared ($0.41 per share)
 (25.4) (25.4)
Balance at September 30, 2021$943.6 $1,026.9 $14.3 $1,984.8 
See accompanying notes to unaudited consolidated financial statements.

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