Exhibit 99

First Interstate BancSystem, Inc. P.O. Box 30918 Billings, Montana 59116 (406) 255-5390 www.firstinterstatebank.com            First Interstate BancSystem, Inc. Fourth Quarter 2008 To our shareholders, First Interstate BancSystem is pleased to announce 2008 net income funding base in 2008, as compared to 2007, and reductions in federal to common stockholders of $67,301,000, or $8.38 per diluted share, funds rates further compressed our net interest margin ratio. as compared to $68,641,000, or $8.25 per diluted share, for 2007. During 2008, we experienced deterioration in credit quality, particu-Return on average common equity was 14.73% in 2008, as compared larly in real estate development loans. This deterioration resulted in to 16.14% in 2007, and return on average assets was 1.12% in 2008, higher levels of nonperforming assets and internally risk classified as compared to 1.37% in 2007. loans. During 2008, we recorded provisions for loan losses of Results for 2008 included a one-time, after tax gain of $16,962,000 $33,356,000 and recorded net charge-offs of $12,858,000, as com-($2.11 per diluted share) from the sale of i_Tech Corporation, our pared to provisions of $7,750,000 and net charge-offs of $2,847,000 technology services subsidiary, in December 2008. The decision to in 2007. sell i_Tech was strategic, as we are now a partner rather than a com-Noninterest income of $128,382,000 in 2008 increased $35,934,000, petitor with our major technology services vendor. or 38.9%, from 2007 primarily due to the one-time gain recorded on Noted Fourth Quarter Financial Data the sale of i_Tech and noninterest income of the acquired First West- ern entities. Exclusive of the acquired First Western entities and the Fourth quarter 2008 income to common stockholders, exclusive of the gain on the sale of i_Tech, 2008 noninterest income decreased one-time gain from the sale of i_Tech, was $227,000, or $0.03 per $829,000, or less than 1.0%, as compared to 2007. Increases in diluted share, as compared to $15,271,000, or $1.86 per diluted share, income from other service charges, commissions and fees and in-for fourth quarter 2007. Our fourth quarter 2008 net income was sub- come from the origination and sale of loans of $1,784,000 and stantially lowered by the adjustments discussed below. $1,045,000, respectively, were offset by nonrecurring income re- corded during 2007. During 2007, we recorded a nonrecurring tech-Net interest income of $59,509,000 for fourth quarter 2008, increased nology services contract termination fee of $2,037,000 and nonrecur-$8,071,000, or 15.7%, compared to fourth quarter 2007, primarily due ring gains of $737,000 on the conversion and subsequent sale of to net interest income of the First Western banking entities acquired in MasterCard stock and $986,000 on the sale of mortgage servicing January 2008. Our fourth quarter 2008 net interest margin declined to rights. 4.13%, compared to 4.41% for fourth quarter 2007, largely due to the            First Western acquisition. In conjunction with the acquisition, we in- Noninterest expense of $222,326,000 in 2008 increased curred indebtedness to acquire nonearning assets, particularly good- $43,459,000, or 24.3%, as compared to 2007. Exclusive of the ex-will. In addition, interest free funding sources, including noninterest pense of the acquired First Western entities, which included a bearing deposits and common equity comprised a smaller percentage $1,286,000 “other than temporary” of our funding base in 2008, as compared to 2007, and reductions in securities, noninterest expense increased $16,374,000, or 9.2%, in federal funds rates further compressed our net interest margin ratio. 2008, as compared to 2007. During 2008, we recorded impairment Our fourth quarter 2008 net FTE interest margin ratio declined to 4.13 %, of $10,940,000 on mortgage servicing rights, compared to compared to 4.30% for third quarter 2008, primarily due to reductions in $1,702,000 in 2007. Most of this impairment occurred during the federal funds rates to near 0.0%. fourth quarter of 2008. Our 2008 FDIC insurance premiums in- creased $1,805,000 from 2007 due to a one-time deposit insurance During fourth quarter 2008, we recorded provisions for loan losses of credit available -managed” banks that was to “well $20,036,000 compared to $2,125,000 for fourth quarter 2007 and 2008. In addition, salaries, wages and benefits expense increased $5,636,000 for third quarter 2008. The significant fourth quarter 2008 $3,641,000, or 3.7%, during 2008 (exclusive of expense of the ac-provision increases reflect our assessment of the estimated effects of quired banks), as compared to 2007. Expense increases in 2008 did current economic conditions on our loan portfolio. Recessionary fac- not include nonrecurring charges $1,500,000 related to an indemnifi-tors resulted in deterioration of credit quality in 2008. cation agreement and other loss accruals recorded during fourth            quarter 2007. Fourth quarter 2008 noninterest income of $52,478,000 increased $29,423,000, or 127.6%, from the same period in 2007 primarily due While 2008 was not a record year for our organization, we are to recognition of a pre-tax gain of $27,096,000 on the sale of i_Tech. pleased with our solid performance in one of the most challenging            banking environments our nation has ever faced. Montana, Wyo-Noninterest expense was $64,398,000 during fourth quarter 2008, an ming and South Dakota have not been as severely impacted by the increase of $15,468,000, or 31.6%, from the same period in 2007. current recession as other areas of the nation, but we have felt and During fourth quarter 2008, we recorded impairment on mortgage will continue to experience adverse effects and earnings pressure. servicing rights of $10,045,000, as compared to $1,491,000 during the            same period in 2007. Salaries, wages and benefits expenses in- As we address current economic and banking challenges, our focus creased $2,691,000 during fourth quarter 2008 as compared to the in 2009 is on building capital, improving liquidity, improving earnings, same period in 2007 largely due to the acquired First Western entities. managing loan quality, completing the integration of the acquired In addition, amortization expense related to mortgage servicing rights First Western entities and addressing short-term and long-term suc-increased $813,000 and core deposit intangible amortization expense cession issues. increased $598,000 during fourth quarter 2008, as compared to the            same period in 2007. Significant fourth quarter 2008 expenses did not Through national and global economic disruptions, changing legisla-include nonrecurring charges of $1,500,000 related to an indemnifica- tive and political climates and the every-day challenges of managing tion agreement and other loss accruals recorded in fourth quarter our business, our devoted team of employees, directors and share-2007. holders remains committed to success. Our company was built on strong values and will remain committed to those values especially Annual Results during these challenging times. Net interest income in 2008 of $235,377,000 increased 17.9% from 2007 primarily due to the net interest income of the acquired First            Western entities. Our 2008 net interest margin ratio of 4.25% de- creased 21 basis points from 4.46% in 2007, largely due to the First            Western acquisition. In conjunction with the acquisition, we in curred            indebtedness to acquire nonearning assets, particularly goodwill. In            Lyle R. Knight Terrill R. Moore addition, interest free funding sources, including noninterest bearing President            Executive Vice President deposits and common equity comprised a smaller percentage of our            Chief Executive Officer            Chief Financial Officer

Fourth Quarter 2008 Condensed Consolidated Statements of Income            Condensed Consolidated Balance Sheets            Three Months Ended Twelve Months Ended            December 31, December 31, December 31, (Unaudited) 2008 2007 2008 2007 (Unaudited) 2008 2007 (In thousands, except per share data) (In thousands) Total interest income $ 86,814. ^{$82,773 $} 355,919 $325,557 ASSETS            Total interest expense 27,305..... ^31,335 120,542 125,954 Cash and due from banks $ 205,070 $ 181,743 Net interest income 59,509... ^51,438 235,377 199,603 Federal funds sold. 107,502 60,635 Provision for loan losses 20,036 ... ^2,125 33,356 7,750 Interest bearing deposits .... 1,458 6,868 Net interest income after            Investment securities ... 1,072,276 1,128,657 provision for loan losses 39,473 ^49,313 ..... 202,021 191,853 Loans..... 4,772,813 3,558,980 Noninterest income ... 52,478 ^23,055 128,382 92,448 Less: allowance for loan losses 87,316 ..... 52,355 Noninterest expense .. 64,398 ^48,930 222,326 178,867 Net loans. 4,685,497 3,506,625 Income before taxes .. 27,553 ^23,438 108,077 105,434 Goodwill... 183,673 37,380 Income taxes..... 9,501 ^8,167 37,429 36,793 Premises & equipment, net .. 177,799 124,041 Net income... 18,052 ^15,271 70,648 68,641 Company owned life insurance 69,515........ 67,076 Less: preferred stock dividends 863 3,347 Accrued interest receivable 38,694.. 32,215zx .. Net income to common stockholders $ 17,189 15,271 $ 67,301 68,641 Mortgage servicing rights ... 11,002 21,715 Core deposit intangible assets 12,682 ........ 257 Other assets... 66,179 49,585 Total Assets..... $6,628,347 $ 5,216,797 Data Per Common Share LIABILITIES AND STOCKHOLDERS’ EQUITY            Deposits... $ 5,174,259 $3,999,401 Diluted EPS         .......... $2.13 $ ^1.86 $8.38 $8.25 0.65 2.60 Federal funds purchased .... 30,625 Dividends.... ^0.65 2.97 Securities sold under repurchase agreements.. 525,501 604,762 Book value to common stockholders 62.00.... 55.51 Accrued interest payable .... 20,531 21,104 Tangible book value to common stockholders 35.68 50.84 ... * ** Accounts payable & accrued expenses 51,290 30,117... Appraised value ...... 79.75 87.75 Other borrowed funds... 79,216 8,730 * Based on the latest independent appraised minority share valuation as of September 30, 2008, Long — term debt... 84,148 5,145 ** Based on the independent appraised minority share valuation as of September 30, 2007, effective for Subordinated debentures ... 123,715 103,095 Total Liabilities. 6,089,285 4,772,354 Stockholders’ equity..... 539,062 444,443 Total Liabilities and Stockholders’ Equity $6,628,347 $5,216,797 Selected Ratios            Three Months Ended Twelve Months Ended            December 31, December 31, (Unaudited) 2008 2007 2008 2007 Quarterly Averages PERFORMANCE Three Months Ended December 31, Return on average common equity 14.34% ^13.80% .. 14.73% 16.14% (Unaudited) 2008 2007 % Change Return on average assets 1.10%         .. ^1.18% 1.12% 1.37% (In thousands) Net interest margin, 4.13%FTE... ^4.41% 4.25% 4.46% Efficiency ratio ... 57.51% ^65.68% 61.12% 61.25% Assets... 6,550,320 5,148,266 27.2% Loans... 4,734,767 3,534,939 33.9% CRE DIT QUALITY (Period End) Investment securities 1,050,101. 1,019,467 3.0% Provision for loan losses to average loans 0.74% 0.22% Deposits ... ..... 5,100,850 4,015,648 27.0% Net charge offs to average loans 0.28% 0.08% Common stockholders’ equity 476,687 .. 438,908 8.6% Allowance for loan losses to total 1.83% loans 1.47%..... Common shares outstanding 7,915... 8,039 -1.5% Allowance for loan losses to non-accruing loans...... 101.97% 165.93% Nonperforming assets to total loans & 2.03% 1.00%other real estate owned... CAPITAL ADEQUACY & LIQUIDITY Leverage capital ratio .... 7.13% 9.92% Average loans to average deposits 92.50%...... 88.62%