EXHIBIT 99.1

FOR IMMEDIATE RELEASE
Date Submitted:            January 24, 2006
NASDAQ Symbol:       FBMI

Contacts: NEWS RELEASE

Samuel G. Stone
Executive Vice President and
Chief Financial Officer
Phone: (989) 466-7325

FIRSTBANK CORPORATION ANNOUNCES
FOURTH QUARTER AND YEAR-TO-DATE 2005 RESULTS

Highlights Include:

• Earnings per share (diluted) of $0.46 for the fourth quarter of 2005, up 7% from $0.43 in the fourth quarter of 2004

• Earnings per share (diluted) of $1.72 in the full year of 2005 compared to $1.71 in 2004

• Integration efforts substantially and successfully completed for Keystone Community Bank (Kalamazoo/Portage and Southwest Michigan)

• Assets exceed $1 Billion

Alma, Michigan (FBMI) — Thomas R. Sullivan, President and Chief Executive Officer of Firstbank Corporation, announced earnings per share of $0.46 for the fourth quarter of 2005, compared to $0.43 for the fourth quarter of 2004, an increase of 7.0%. Net income was $2,868,000 for the quarter ended December 31, 2005, compared to $2,455,000 for the quarter ended December 31, 2004. Returns on average assets and average equity for the fourth quarter of 2005 were 1.09% and 12.2%, respectively, compared with 1.21% and 13.5%, respectively, in the fourth quarter of 2004. All per share amounts are fully diluted amounts and have been adjusted to reflect the 5% stock dividend paid in December 2005.

For full year 2005, earnings per share of $1.72 compared to $1.71 for 2004, an increase of 0.6%. Net income was $10,110,000 for 2005, compared to $10,358,000 for 2004. Returns on average assets and average equity for 2005 were 1.15% and 12.8%, respectively, compared with 1.32% and 13.0%, respectively, in 2004. The capital management strategies of share repurchases and self tender executed primarily in 2004 benefited earnings per share and return on equity in 2005.

Growth in Firstbank’s balance sheet continued, as total assets at the end of 2005 exceeded $1 billion. The addition of Keystone Community Bank through the acquisition of Keystone Financial Corporation, completed on October 1, 2005, increased Firstbank’s balance sheet growth. Total portfolio loans at December 31, 2005, were 31% above the level at December 31, 2004, and excluding the balances of Keystone Community Bank were up 8.7%. Commercial and commercial real estate loans increased 45% above the year-ago level, and excluding Keystone Community Bank were up 10.5%. Residential mortgage loans increased 18% from year-ago, and excluding Keystone were up 9.7%. Total deposits as of December 31, 2005, were 35% above the year-ago level. Excluding Keystone deposits, total deposits increased 10%.

Firstbank’s net interest margin, at 4.34% in the fourth quarter of 2005, decreased 0.12% from the 4.46% level achieved in the third quarter of 2005. Approximately half of the decline was due to the cost of funds used in the cash portion of the purchase consideration for Keystone, as expected. Other factors squeezing the margin include a growing reliance on wholesale funding, competitive pressures to increase deposit rates on core deposits, and shifting preference among borrowers for more fixed rate funding where spreads are narrow due to competition and the flat yield curve. For the year 2005, the net interest margin was 4.40%, down 0.07% from 2004, with the partial-year impact of Keystone also influencing this comparison. The flattening of the yield curve in 2005 and competitive factors prevented Firstbank’s net interest margin from increasing in a rising rate environment.

Mr. Sullivan stated, “We are extremely pleased with the success of our expansion into the Kalamazoo and Southwestern Michigan markets with the addition of Keystone Community Bank. We could not have asked for a better group of people or a better fit with the quality people we already have in Firstbank. The efficiencies expected from our approach to consolidated operational support are now being fully realized at the beginning of 2006, and the conversion of Keystone to Firstbank’s computer systems and support units have gone well and have not disturbed Keystone’s good customer service. Meanwhile, we continue to emphasize increasing the depth of our presence in all of our markets by providing more service to existing customers and winning new customers. We had good quarterly earnings comparisons in the initial quarter of operating with Keystone in the fold, and that is a credit to the hard work of all of our people on behalf of our shareholders.”

Total non-interest expenses in the fourth quarter of 2005 increased 5.2% from the fourth quarter of 2004 primarily as a result of adding Keystone Community Bank in the Kalamazoo market.

Shareholders’ equity increased 21.4% in the fourth quarter of 2005, primarily due to the acquisition of Keystone. Firstbank did not repurchase shares in the fourth quarter of 2005, although board authorization remains in place for the repurchase of up to approximately $5.5 million in market value of shares. The ratio of average equity to average assets stood at 8.9% in the fourth quarter of 2005, similar to the 9.0% ratio in the fourth quarter of 2004, indicating that a strong level of equity capital has been maintained subsequent to the addition of Keystone.

Firstbank’s mortgage servicing portfolio was $473.3 million as of December 31, 2005, compared to $472.2 million at September 30, 2005, and $472.1 million at December 31, 2005.

As expected, Firstbank’s asset quality measures showed some deterioration from their historically strong levels. Net charge-offs increased to $618,000 in the fourth quarter of 2005, or 0.28% annualized as a percentage of average loans, compared to $80,000, or 0.05% annualized as a percentage of average loans in the third quarter of 2005. The ratio of non-performing loans (including loans past due over 90 days) to loans was 0.82% at December 31, 2005, compared to 0.42% at September 30, 2005, and 0.28% at December 31, 2004. The increase in the ratio of non-performing loans in the fourth quarter of 2005 was primarily related to one $3 million credit for which specific reserves had been established previously in recognition of concern about the probability of loss. The total provision for loan losses of $295,000 in 2005 was less than net charge-offs. Most of the loans charged off were held in the portfolio prior to 2005, and probable loss had been recognized and included in the allowance for loan losses in prior periods. The level of net charge-offs to average loans, at 0.17% in 2005, remains at a level that is considered by most to be in a favorable range for the industry. Provision expense was increased in 2005 compared to 2004 in recognition of the changes in asset quality measures and as required to maintain the allowance for loan losses at an appropriate level.

Firstbank Corporation, headquartered in Alma, Michigan, is a six bank financial services company with assets of $1.1 billion and 39 banking offices serving Michigan’s Lower Peninsula. Bank subsidiaries include: Firstbank – Alma; Firstbank (Mt. Pleasant); Firstbank – West Branch; Firstbank – Lakeview; Firstbank – St. Johns; and Keystone Community Bank.

This press release contains certain forward-looking statements that involve risks and uncertainties. When used in this press release the words “anticipate,” “believe,” “expect,” “hopeful,” “potential,” “should,” and similar expressions identify forward-looking statements. Forward-looking statements include, but are not limited to, statements concerning future business growth, increases in interest rates and positioning of balance sheets to benefit net interest margins and earnings. Such statements are subject to certain risks and uncertainties which could cause actual results to differ materially from those expressed or implied by such forward-looking statements, including, but not limited to, economic, competitive, governmental and technological factors affecting the Company’s operations, markets, products, services, interest rates and fees for services. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release.

FIRSTBANK CORPORATION
CONSOLIDATED STATEMENTS OF INCOME
(Dollars in thousands except per share data)
UNAUDITED

	Three Months Ended:						Twelve Months Ended:
	Dec 31 2005		Sep 30 2005		Dec 31 2004		Dec 31 2005		Dec 31 2004
Interest income:
Interest and fees on loans	$15,631		$12,199		$ 10,734		$50,030		$ 41,350
Investment securities
Taxable	501		489		443		$  1,952		$   1,655
Exempt from federal income tax	244		233		247		956		951
Short term investments	88		40		50		192		136
Total interest income	16,464		12,961		11,474		53,130		44,092
Interest expense:
Deposits	4,536		2,972		1,974		12,368		7,453
Notes payable and other borrowing	1,670		1,343		1,135		5,446		4,257
Total interest expense	6,206		4,315		3,109		17,814		11,710
Net interest income	10,258		8,646		8,365		35,316		32,382
Provision for loan losses	141		73		80		295		(425	)
Net interest income after provision for loan losses	10,117		8,573		8,285		35,021		32,807
Noninterest income:
Gain on sale of mortgage loans	362		438		565		1,686		2,663
Service charges on deposit accounts	856		778		731		3,137		2,813
Gain on sale of securities	0		5		33		34		54
Mortgage servicing	79		48		(13	)	205		(55	)
Other	1,055		1,301		1,126		4,670		4,576
Total noninterest income	2,352		2,570		2,442		9,732		10,051
Noninterest expense:
Salaries and employee benefits	4,481		3,896		4,051		16,100		15,718
Occupancy and equipment	1,244		1,011		988		4,240		3,866
Amortization of intangibles	168		75		75		394		302
FDIC insurance premium	22		20		21		84		85
Other	2,405		2,308		2,773		9,122		8,390
Total noninterest expense	8,320		7,310		7,908		29,940		28,361
Income before federal income taxes	4,149		3,833		2,819		14,813		14,497
Federal income taxes	1,281		1,236		364		4,703		4,139
Net Income	$  2,868		$  2,597		$   2,455		$10,110		$ 10,358
Fully Tax Equivalent Net Interest Income	$10,427		$  8,781		$   8,475		35,898		32,865
Per Share Data:
Basic Earnings	$    0.46		$    0.46		$     0.44		$    1.75		$     1.75
Diluted Earnings	$    0.46		$    0.45		$     0.43		$    1.72		$     1.71
Dividends Paid	$    0.21		$    0.21		$     0.19		$    0.83		$     0.75
Performance Ratios:
Return on Average Assets*	1.09	%	1.22	%	1.21	%	1.15	%	1.32	%
Return on Average Equity*	12.2	%	13.5	%	13.5	%	12.8	%	13.0	%
Net Interest Margin (FTE) *	4.34	%	4.46	%	4.52	%	4.40	%	4.47	%
Book Value Per Share+	$  14.91		$  13.66		$   13.04		$  14.91		$   13.04
Average Equity/Average Assets	8.9	%	9.1	%	9.0	%	9.0	%	10.1	%
Net Charge-offs	618		80		294		1,265		621
Net Charge-offs as a % of Average Loans^*	0.28	%	0.05	%	0.18	%	0.17	%	0.10	%

* Annualized
+ Period End
^ Total loans less loans held for sale

FIRSTBANK CORPORATION
CONSOLIDATED BALANCE SHEETS
(Dollars in thousands)
UNAUDITED

	Dec 31 2005		Sep 30 2005		Dec 31 2004
ASSETS
Cash and cash equivalents:
Cash and due from banks	$      36,037		$      24,396		$      23,715
Short term investments	17,295		211		2,057
Total cash and cash equivalents	53,332		24,607		25,772
Securities available for sale	73,811		73,161		72,475
Federal Home Loan Bank stock	6,309		5,563		5,355
Loans:
Loans held for sale	293		204		1,969
Portfolio loans:
Commercial	183,473		116,827		110,261
Commercial real estate	302,471		249,071		225,372
Residential mortgage	272,402		245,250		231,213
Real estate construction	61,067		48,772		47,920
Consumer	57,404		55,666		54,491
Credit card	1,807		1,802		1,830
Total portfolio loans	878,624		717,388		671,087
Less allowance for loan losses	(11,559	)	(10,087	)	(10,581	)
Net portfolio loans	867,065		707,301		660,506
Premises and equipment, net	19,477		17,191		17,658
Goodwill	19,090		4,465		4,465
Other intangibles	3,710		2,165		2,395
Other assets	18,031		26,552		15,540
TOTAL ASSETS	$ 1,061,118		$    861,209		$    806,135
LIABILITIES AND SHAREHOLDERS' EQUITY
LIABILITIES
Deposits:
Noninterest bearing accounts	130,556		107,559		106,208
Interest bearing accounts:
Demand	187,399		157,371		177,067
Savings	133,705		134,679		100,277
Time	315,002		213,988		200,544
Wholesale CD's	44,444		31,595		19,171
Total deposits	811,106		645,192		603,267
Securities sold under agreements to
repurchase and overnight borrowings	43,311		37,465		39,100
FHLB Advances and notes payable	90,634		79,941		71,430
Subordinated Debt	10,310		10,310		10,310
Accrued interest and other liabilities	12,180		11,215		9,164
Total liabilities	967,541		784,123		733,271
SHAREHOLDERS' EQUITY
Preferred stock; no par value, 300,000
shares authorized, none issued
Common stock; 20,000,000 shares authorized *	87,634		65,626		64,713
Retained earnings	6,198		11,584		7,816
Accumulated other comprehensive income/(loss)	(255	)	(124	)	335
Total shareholders' equity	93,577		77,086		72,864
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$ 1,061,118		$    861,209		$    806,135
* Common stock shares issued and outstanding	6,278,035		5,641,491		5,588,244
Asset Quality Ratios:
Non-Performing Loans / Loans^	0.82	%	0.42	%	0.28	%
Non-Perf. Loans + OREO / Loans^ + OREO	0.94	%	0.52	%	0.42	%
Non-Performing Assets / Total Assets	0.78	%	0.43	%	0.35	%
Allowance for Loan Loss as a % of Loans^	1.32	%	1.41	%	1.58	%
Allowance / Non-Performing Loans	160	%	333	%	568	%
Quarterly Average Balances:
Total Portfolio Loans^	$    868,701		$    701,592		$    663,475
Total Earning Assets	957,246		785,503		746,814
Total Shareholders' Equity	92,547		76,256		72,021
Total Assets	1,037,354		842,529		799,688
Diluted Shares Outstanding	6,286,277		5,721,719		5,691,522

^ Total Loans less loans held for sale