EXHIBIT 99

First Interstate BancSystem
Reaching New Heights

To our shareholders,

First Interstate BancSystem reported third quarter 2004 net income of $11,086,000, or $1.39 per diluted share compared to $11,830,000 or $1.50 per diluted share in third quarter 2003. Return on average equity (ROAE) was 15.54% in third quarter 2004 compared to 17.88% last year, return on average assets (ROAA) 1.10% versus 1.24%, and efficiency ratio of 66.10% versus 60.22%.

Net interest income of $37,554,000 in third quarter 2004 was $2,104,000 more than the same period last year. The net interest margin of 4.32% increased 4 basis points over the same period last year. Quarterly average loans grew $121,919,000, or 5%; while quarterly average deposits grew $152,217,000, also 5%.

Non-interest income of $19,722,000 was $2,415,000 or 14% higher than third quarter 2003. Residential real estate revenue continued it’s year over year decline with third quarter 2004 $1,991,000, or 46%, lower than third quarter 2003. In July 2004, the Cut Bank branch was sold resulting in a gain of $1,690,000. Further, in third quarter 2003, investment securities were sold resulting in a $1,594,000 loss. Removing the 2004 Cut Bank gain and 2003 securities loss, non-interest revenue would show a 5% decrease compared to third quarter 2003.

Non-interest expense was $6,091,000, or 19%, higher than the comparable quarter in 2003. In third quarter 2004, we recorded $1,180,000 mortgage servicing rights (MSR) impairment expense compared to $2,585,000 MSR impairment reversal for the third quarter in 2003. Excluding the effect of mortgage servicing impairment and reversal, non-interest expense increased $2,326,000, or 7%.

Year to date net income of $33,376,000 exceeded the first nine months of 2003 by $2,474,000 or 8%. The previously mentioned MSR fluctuations have a negligible year over year financial effect. Fully diluted earnings per share were $4.19, compared to $3.92 for the same period last year. Net interest income was up $7,184,000 due to strong loan and deposit growth. Non-interest revenue was up $74,000, the small increase year over year the result of a $6,593,000, or 51%, decrease in residential real

estate revenue which nearly offsets increases in other revenue categories. Non-interest expense was up $4,051,000, or 4%, from 2003. The efficiency ratio of 64.28% for the first nine months of 2004 was 39 basis points lower than last year.

Dividends of $.42 per share were paid on October 8th.

We are pleased with our financial results through third quarter 2004. Thank you to our talented team of employees, officers, managers and advisory directors who continue to effectively drive our progress on strategic initiatives in a challenging economic environment.

Lyle R. Knight	Terrill R. Moore
President	Chief Financial Officer
Chief Executive Officer

Financial Highlights
Three Months ended September 30

in thousands except per share data	2004		2003		% Change
(unaudited)
OPERATING RESULTS
Net income	$	11,086	$	11,830		-6.3	%
Diluted earnings per share		1.39		1.50		-7.3	%
Dividends per share		0.40		0.32		25.0	%
PERIOD END BALANCES
Assets		4,063,162		3,857,118		5.3	%
Loans		2,674,963		2,566,288		4.2	%
Investment Securities		841,029		770,878		9.1	%
Deposits		3,236,518		3,124,176		3.6	%
Common Stockholders’ Equity		302,299		266,382		13.5	%
Common Shares Outstanding		7,990		7,909		1.0	%
QUARTERLY AVERAGES
Assets		3,998,892		3,789,797		5.5	%
Loans		2,651,383		2,529,464		4.8	%
Investment Securities		799,916		785,380		1.9	%
Deposits		3,202,681		3,050,464		5.0	%
Common Stockholders’ Equity		283,837		262,538		8.1	%
Common Shares Outstanding		7,887		7,848		0.5	%

Third Quarter 2004

Third Quarter 2004

Condensed Consolidated Statements of Income (Unaudited)
(in thousands, except per share data)

	Three Months Ended				Nine Months Ended
	September 30				September 30
	2004		2003		2004		2003
Total interest income	$	48,143	$	46,839	$	141,756	$	141,698
Total interest expense		10,589		11,389		30,666		37,792
Net interest income		37,554		35,450		111,090		103,906
Provision for loan losses		2,387		2,422		7,346		7,422
Net interest income after provision for loan losses		35,167		33,028		103,744		96,484
Noninterest income		19,722		17,307		53,618		53,544
Noninterest expense		37,861		31,770		105,877		101,826
Income before taxes		17,028		18,565		51,485		48,202
Income taxes		5,942		6,735		18,109		17,300
Net income	$	11,086	$	11,830	$	33,376	$	30,902
COMMON SHARE DATA:
Diluted EPS		1.39		1.50		4.19		3.92
Dividends		0.40		0.32		1.14		0.98
Book value						37.88		33.68
Tangible book value						33.20		28.92
Appraised value						*		49.50

* Currently not available, $54.50 as of June 30, 2004

Selected Ratios (Unaudited)

	Three Months Ended						Nine Months Ended
	September 30						September 30
	2004			2003			2004			2003
PERFORMANCE
Return on avg common equity		15.54	%		17.88	%		15.76	%		16.26	%
Return on avg common equity excl. market adj of securities		15.02	%		18.06	%		15.63	%		16.40	%
Return on avg assets		1.10	%		1.24	%		1.13	%		1.12	%
Net interest margin, FTE		4.32	%		4.28	%		4.36	%		4.38	%
Efficiency ratio		66.10	%		60.22	%		64.28	%		64.67	%
CREDIT QUALITY (Period End)
Provision for loan losses to average loans								0.38	%		0.41	%
Net charge offs to average loans								0.20	%		0.28	%
Allowance for loan losses to loans								1.58	%		1.52	%
Allowance for loan losses to non-accruing loans								189.12	%		152.14	%
CAPITAL ADEQUACY & LIQUIDITY
Leverage capital ratio								7.34	%		7.01	%
Avg loans to avg deposits								82.61	%		81.18	%

Condensed Consolidated Balance Sheets (Unaudited)
(In thousands)

	September 30
	2004		2003
ASSETS
Cash and due from banks	$	233,071	$	221,344
Federal funds sold		56,415		57,310
Interest bearing deposits		6,816		695
Investment securities		841,029		770,878
Loans		2,674,963		2,566,288
Less: allowance for loan losses		42,396		38,782
Net loans		2,632,567		2,527,506
Premises & equipment, net		120,015		108,438
Accrued interest receivable		22,015		21,805
Goodwill and core deposit intangibles		39,878		41,368
Other real estate owned, net		1,647		1,627
Other assets		109,709		106,147
Total Assets	$	4,063,162	$	3,857,118
LIABILITIES AND STOCKHOLDERS’ EQUITY
Deposits	$	3,236,518	$	3,124,176
Securities sold under repurchase agreements		401,078		335,012
Other liabilities		31,443		32,957
Other borrowed funds		8,051		9,190
Long-term debt		42,535		49,401
Subordinated debenture and trust preferred securities		41,238		40,000
Total Liabilities		3,760,863		3,590,736
Common stockholders’ equity		302,299		266,382
Total Liabilities and Stockholders’ Equity	$	4,063,162	$	3,857,118

Navigating our course

First Interstate BancSystem

P.O. Box 30918 • Billings, Montana 59116 • (406) 255-5390
www.firstinterstatebank.com