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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 March 31, 2021
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) 255-5390
_________________________________________________________________________________________________ 

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:
March 31, 2021 – Class A common stock41,583,430 
March 31, 2021 – Class B common stock20,646,913 




Quarterly Report on Form 10-Q
FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
Index
March 31, 2021
  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


Table of Contents
FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
CONSOLIDATED BALANCE SHEETS
(In millions, except share data)
(Unaudited)
March 31,
2021
December 31,
2020
Assets
Cash and due from banks$254.0 $261.4 
Interest bearing deposits in banks1,941.9 2,015.3 
Federal funds sold0.1 0.1 
Total cash and cash equivalents2,196.0 2,276.8 
Investment securities:
Available-for-sale4,020.1 4,008.7 
Held-to-maturity, net (estimated fair values of $855.6 and $55.0 at March 31, 2021 and December 31, 2020, respectively)
866.3 51.6 
Total investment securities4,886.4 4,060.3 
Mortgage loans held for sale, at fair value57.2 74.0 
Loans held for investment, net of deferred fees and costs9,863.2 9,807.5 
Allowance for credit losses136.6 144.3 
Net loans held for investment9,726.6 9,663.2 
Goodwill621.6 621.6 
Company-owned life insurance297.6 296.4 
Premises and equipment, net of accumulated depreciation305.5 312.3 
Core deposit intangibles, net of accumulated amortization48.6 51.2 
Accrued interest receivable50.0 51.1 
Mortgage servicing rights, net of accumulated amortization and impairment reserve28.0 24.0 
Other real estate owned (“OREO”)2.2 2.5 
Other assets223.7 215.3 
Total assets$18,443.4 $17,648.7 
Liabilities and Stockholders’ Equity
Deposits:
Non-interest bearing$5,004.0 $4,633.5 
Interest bearing10,090.0 9,583.5 
Total deposits15,094.0 14,217.0 
Securities sold under repurchase agreements1,052.6 1,091.4 
Accounts payable and accrued expenses133.8 144.4 
Accrued interest payable6.9 5.8 
Deferred tax liability, net19.9 27.2 
Long-term debt112.4 112.4 
Allowance for credit losses on off-balance sheet credit exposures3.4 3.7 
Subordinated debentures held by subsidiary trusts87.0 87.0 
Total liabilities16,510.0 15,688.9 
Stockholders’ equity:
Nonvoting noncumulative preferred stock without par value; authorized 100,000 shares; no shares issued and outstanding as of March 31, 2021 or December 31, 2020
  
Common stock938.5 941.1 
Retained earnings988.2 962.1 
Accumulated other comprehensive income, net6.7 56.6 
Total stockholders’ equity1,933.4 1,959.8 
Total liabilities and stockholders’ equity$18,443.4 $17,648.7 
See accompanying notes to unaudited consolidated financial statements.
3


Table of Contents
FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
CONSOLIDATED STATEMENTS OF INCOME
(In millions, except per share data)
(Unaudited)
 Three Months Ended March 31,
 20212020
Interest income:
Interest and fees on loans$107.8 $112.0 
Interest and dividends on investment securities:
Taxable15.8 17.2 
Exempt from federal taxes1.4 0.5 
Interest on deposits in banks0.3 2.5 
Total interest income125.3 132.2 
Interest expense:
Interest on deposits2.3 7.3 
Interest on securities sold under repurchase agreements0.1 0.5 
Interest on other debt1.5 0.3 
Interest on subordinated debentures held by subsidiary trusts0.7 1.0 
Total interest expense4.6 9.1 
Net interest income120.7 123.1 
(Reversal of) provision for credit losses(5.1)29.0 
Net interest income after provision for (reversal of) credit losses125.8 94.1 
Non-interest income:
Payment services revenues10.2 10.2 
Mortgage banking revenues11.6 10.9 
Wealth management revenues6.3 6.2 
Service charges on deposit accounts3.8 5.4 
Other service charges, commissions, and fees2.1 2.1 
Investment securities gains (losses), net  
Other income4.1 3.6 
Total non-interest income38.1 38.4 
Non-interest expense:
Salaries and wages39.0 39.9 
Employee benefits16.1 14.2 
Outsourced technology services8.1 7.8 
Occupancy, net7.3 7.3 
Furniture and equipment4.4 2.8 
OREO expense, net of income(0.1)(0.5)
Professional fees3.4 2.7 
FDIC insurance premiums1.6 1.6 
Core deposit intangibles amortization2.5 2.9 
Other expenses16.1 16.3 
Total non-interest expense98.4 95.0 
Income before income tax expense65.5 37.5 
Income tax expense14.1 8.2 
Net income$51.4 $29.3 
Earnings per common share (Basic)$0.83 $0.45 
Earnings per common share (Diluted)0.83 0.45 
Weighted average common shares outstanding (Basic)61,591,877 64,790,186 
Weighted average common shares outstanding (Diluted)61,714,063 64,937,107 
See accompanying notes to unaudited consolidated financial statements.
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FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
(In millions)
(Unaudited)
 Three Months Ended March 31,
 20212020
Net income$51.4 $29.3 
Other comprehensive (loss) income, before tax:
Investment securities available-for sale:
Change in net unrealized (losses) gains during period(66.8)39.2 
Unrealized gain on derivatives(0.1) 
Defined benefit post-retirement benefits plans:
Change in net actuarial loss (0.2)
Other comprehensive (loss) income, before tax(66.9)39.0 
Changes in deferred taxes related to other comprehensive loss (income)17.0 (10.2)
Other comprehensive (loss) income, net of tax(49.9)28.8 
Comprehensive income, net of tax$1.5 $58.1 
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 March 31,
Common
stock
Retained
earnings
Accumulated
other
comprehensive
income (loss)
Total
stockholders’
equity
Balance at December 31, 2020$941.1 $962.1 $56.6 $1,959.8 
Net income 51.4  51.4 
Other comprehensive loss, net of tax expense  (49.9)(49.9)
Common stock transactions:
127,180 common shares purchased and retired
(5.4)  (5.4)
604 common shares issued
    
239,525 non-vested common shares issued
    
19,068 non-vested common shares forfeited or canceled
    
40,663 stock options exercised, net of 6,177 shares tendered in payment of option price and income tax withholding amounts
0.4   0.4 
Stock-based compensation expense2.4   2.4 
Common cash dividends declared ($0.41 per share)
 (25.3) (25.3)
Balance at March 31, 2021$938.5 $988.2 $6.7 $1,933.4 
Balance at December 31, 2019$1,049.3 $953.6 $11.0 $2,013.9 
Cumulative change related to the adoption of ASU 2016-13 (24.1) (24.1)
Adjusted balance at January 1, 20201,049.3 929.5 11.0 1,989.8 
Net income 29.3  29.3 
Other comprehensive income, net of tax expense  28.8 28.8 
Common stock transactions:
1,093,259 common shares purchased and retired
(32.6)  (32.6)
327,367 non-vested common shares issued
    
2,570 non-vested common shares forfeited or canceled
    
73,351 stock options exercised, net of 23,175 shares tendered in payment of option price and income tax withholding amounts
0.6   0.6 
Stock-based compensation expense1.4   1.4 
Common cash dividends declared ($0.94 per share)
 (61.2) (61.2)
Balance at March 31, 2020$1,018.7 $897.6 $39.8 $1,956.1 
See accompanying notes to unaudited consolidated financial statements.








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FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
CONSOLIDATED STATEMENTS OF CASH FLOWS
(In millions)
(Unaudited)
 Three Months Ended March 31,
 20212020
Cash flows from operating activities:
Net income$51.4 $29.3 
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for (reversal of) credit losses(5.1)29.0 
Net gain on disposal of premises and equipment(0.4)(0.1)
Depreciation and amortization11.4 9.7 
Net premium amortization on investment securities7.7 2.4 
Realized and unrealized net gains on mortgage banking activities(3.9)(9.1)
Net gain on sale of investments in unrelated entities (1.0)
Net gain on sale of OREO(0.1)(0.6)
Mortgage servicing rights (recovery) impairment(5.9)2.9 
Deferred taxes9.6 (4.4)
Net increase in cash surrender value of company-owned life insurance(1.2)(1.5)
Stock-based compensation expense2.4 1.4 
Originations of mortgage loans held for sale(156.4)(211.3)
Proceeds from sales of mortgage loans held for sale177.2 224.9 
Changes in operating assets and liabilities:
Decrease in interest receivable1.1 0.4 
Increase in other assets(7.8)(34.9)
Increase (decrease) in accrued interest payable1.1 (1.8)
(Decrease) increase in accounts payable and accrued expenses(10.6)6.0 
Net cash provided by operating activities70.5 41.3 
Cash flows from investing activities:
Purchases of investment securities:
Held-to-maturity(825.1) 
Available-for-sale(378.6)(419.0)
Proceeds from sales, maturities, and pay-downs of investment securities:
Held-to-maturity9.3 22.0 
Available-for-sale293.7 415.5 
Extensions of credit to clients, net of repayments(60.7)7.1 
Recoveries of loans charged-off2.0 1.5 
Proceeds from sale of OREO0.7 1.8 
Proceeds from sale of investments in unrelated entities 2.2 
Capital expenditures, net of sales(0.5)(4.9)
Net cash (used in) provided by investing activities$(959.2)$26.2 
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FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
CONSOLIDATED STATEMENTS OF CASH FLOWS (continued)
(In millions)
(Unaudited)
Three Months Ended March 31,
20212020
Cash flows from financing activities:
Net increase (decrease) in deposits$877.0 $(98.4)
Net decrease in securities sold under repurchase agreements(38.8)(83.5)
Proceeds from issuance of common stock0.4 0.6 
Purchase and retirement of common stock(5.4)(32.6)
Dividends paid to common stockholders(25.3)(61.2)
Net cash provided by (used in) financing activities807.9 (275.1)
Net decrease in cash and cash equivalents(80.8)(207.6)
Cash and cash equivalents at beginning of period2,276.8 1,076.8 
Cash and cash equivalents at end of period$2,196.0 $869.2 
Supplemental disclosures of cash flow information:
Cash paid during the period for income taxes$21.0 $11.5 
Cash paid during the period for interest expense3.5 10.9 
Supplemental disclosures of non-cash investing and financing activities:
Right-of-use assets obtained in exchange for operating lease liabilities 3.2 
Transfer of loans to other real estate owned0.3 0.9 
Capitalization of internally originated mortgage servicing rights 0.1 2.0 
See accompanying notes to unaudited consolidated financial statements.
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FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
NOTES TO UNAUDITED CONSOLIDATED FINANCIAL STATEMENTS
(Dollars in millions, except share and per share data)

(1)    Basis of Presentation
In the opinion of management, the accompanying unaudited consolidated financial statements of First Interstate BancSystem, Inc., First Interstate Bank (“FIB”), and its other subsidiaries (collectively, the “Company”) contain all adjustments (all of which are of a normal recurring nature) necessary to present fairly the financial position of the Company at March 31, 2021 and December 31, 2020, the results of operations, changes in stockholders’ equity, and cash flows for each of the three month period ended March 31, 2021 and 2020, in conformity with U.S. generally accepted accounting principles (“GAAP”). The balance sheet information at December 31, 2020 is derived from audited consolidated financial statements. Certain reclassifications, none of which were material, have been made to conform prior year financial statements to the March 31, 2021 presentation. These reclassifications did not change previously reported net income or stockholders’ equity.
These unaudited consolidated financial statements should be read in conjunction with the audited consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020, which includes a description of significant accounting policies. Operating results for the three months ended March 31, 2021 are not necessarily indicative of the results that may be expected for the year ending December 31, 2021.
(2)    Investment Securities

The amortized cost and the approximate fair values of investment securities are summarized as follows:
March 31, 2021Amortized
Cost
Gross
Unrealized
Gains
Gross
Unrealized
Losses
Estimated
Fair
Value
Available-for-Sale:
U.S. Treasury notes$1.0 $ $ $1.0 
State, county, and municipal securities458.0 1.8 (14.7)445.1 
Obligations of U.S. government agencies334.9 0.4 (11.8)323.5 
U.S. agency residential mortgage-backed securities & collateralized mortgage obligations2,866.0 56.3 (20.8)2,901.5 
Private mortgage-backed securities6.5 0.1  6.6 
Corporate securities344.6 3.7 (5.9)342.4 
Total$4,011.0 $62.3 $(53.2)$4,020.1 

March 31, 2021Amortized
Cost
Gross
Unrealized
Gains
Gross
Unrealized
Losses
Estimated
Fair
Value
Held-to-Maturity:
State, county, and municipal securities$74.1 $2.7 $(0.9)$75.9 
U.S agency residential mortgage-backed securities & collateralized mortgage obligations788.2 0.2 (12.8)775.6 
Corporate securities3.9 0.1  4.0 
Other investments0.1   0.1 
Total$866.3 $3.0 $(13.7)$855.6 

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FIRST INTERSTATE BANCSYSTEM, INC. AND SUBSIDIARIES
NOTES TO UNAUDITED CONSOLIDATED FINANCIAL STATEMENTS
(Dollars in millions, except share and per share data)
December 31, 2020Amortized
Cost
Gross
Unrealized
Gains
Gross
Unrealized
Losses
Estimated
Fair
Value
Available-for-Sale:
State, county, and municipal securities$462.1 $4.8 $(1.0)$465.9 
Obligations of U.S. government agencies332.9 1.0 (2.0)331.9 
U.S. agency residential mortgage-backed securities & collateralized mortgage obligations2,830.8 69.3 (2.5)2,897.6 
Private mortgage-backed securities10.9 0.1 (0.1)10.9 
Corporate securities
295.8 6.5 (0.1)302.2 
Other investments
0.2   0.2 
Total$3,932.7 $81.7 $(5.7)$4,008.7 

December 31, 2020Amortized
Cost
Gross
Unrealized
Gains
Gross
Unrealized
Losses
Estimated
Fair
Value
Held-to-Maturity:
State, county, and municipal securities$46.6 $3.2 $ $49.8 
U.S. agency residential mortgage-backed securities & collateralized mortgage obligations1.0 0.1  1.1 
Corporate securities
3.9 0.1  4.0 
Other investments0.1   0.1 
Total$51.6 $3.4 $ $55.0 
There were no material gross realized gains and no material gross losses on the disposition of available-for-sale investment securities during the three month periods ended March 31, 2021 and 2020.
As of March 31, 2021, the Company had general obligation securities with amortized costs of $60.9 million included in state, county, and municipal securities, of which $25.6 million, or 42.0%, were issued by political subdivisions or agencies within the states of Idaho, Montana, Oregon, South Dakota, Washington, and Wyoming.
The following tables show the gross unrealized losses and fair values of investment securities, aggregated by investment category, and the length of time individual investment securities have been in a continuous unrealized loss position as of March 31, 2021 and December 31, 2020. There were no held-to-maturity securities in a continuous unrealized loss position at December 31, 2020.
 Less than 12 Months12 Months or MoreTotal
March 31, 2021Fair
Value
Gross
Unrealized
Losses
Fair
Value
Gross
Unrealized
Losses
Fair
Value
Gross
Unrealized
Losses
Available-for-Sale:      
State, county, and municipal securities$444.8 $(14.7)$ $ $444.8 $(14.7)
Obligations of U.S. government agencies
323.6 (11.8)  323.6 (11.8)
U.S. agency residential mortgage-backed securities & collateralized mortgage obligations2,750.0 (20.7)11.3 (0.1)2,761.3