8-K

SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the
Securities Exchange Act of 1934

Date of Report: July 2, 2007

FIRSTBANK CORPORATION
(Exact name of registrant as
specified in its charter)

Michigan
(State or other
jurisdiction of
incorporation) 000-14209
(Commission
File Number) 38-2633910
(IRS Employer
Identification no.)

311 Woodworth Avenue
Alma, Michigan
(Address of principal executive office) 48801
(Zip Code)

Registrant’s telephone number,
including area code: (989) 463-3131

[X]      Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425).
[_]      Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12).
[_]      Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240-14d-2(b)).
[_]      Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)).

ITEM 8.01      OTHER EVENTS

On July 1, 2007, the merger of ICNB Financial Corporation with and into Firstbank Corporation became effective. A copy of the press release announcing the merger is filed as Exhibit 99.1 to this report.

ITEM 9.01      FINANCIAL STATEMENTS AND EXHIBITS

(d)     Exhibits.

Exhibit Number		Description
	99.1	Press Release of Firstbank Corporation announcing that the ICNB Financial Corporation merger with and into Firstbank Corporation is effective.

SIGNATURE

        Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

Dated: July 2, 2007 FIRSTBANK CORPORATION
(Registrant)


By: /s/ Samuel G. Stone
      ——————————————
      Samuel G. Stone
      Chief Financial Officer

EX-99

FOR IMMEDIATE RELEASE:
Date Submitted: July 2, 2007
NASDAQ Symbol: FBMI NEWS RELEASE

Contacts: Thomas R. Sullivan
President & Chief Executive Officer
(989) 466-7347
Samuel G. Stone
Executive Vice President &
Chief Financial Officer
(989) 466-7325

Firstbank Corporation Announces the Closing of
the ICNB Financial Corporation Acquisition

Alma, MI, July 2, 2007, Firstbank Corporation (NASDAQ: FBMI), a Michigan bank holding company, today announced that it has completed its acquisition of ICNB Financial Corporation, a bank holding company, and its wholly-owned subsidiary bank. ICNB’s subsidiary bank, formerly known as Ionia County National Bank, converted from a national bank to a Michigan state-chartered bank effective July 1, 2007, with a new name Firstbank – West Michigan.

Firstbank – West Michigan will continue to operate as a separately chartered community bank, and Mr. James D. Fast continues as President and Chief Executive Officer of the bank.

Thomas R. Sullivan, President and Chief Executive Officer of Firstbank Corporation, said, “We are pleased to have completed the regulatory and merger process on schedule, and we welcome all of ICNB’s shareholders, customers, and employees to the Firstbank family. We look forward to the smooth integration of our companies and hope to complete the conversion of all the core systems by the end of the third quarter of 2007.”

Based on Firstbank’s closing stock price on June 29, 2007, the transaction is valued at $36.4 million, representing a price of 160% of ICNB tangible equity at March 31, 2007, and a premium to core deposits of 9.1%. Firstbank Corporation, headquartered in Alma, Michigan, is now a seven bank financial services company with assets of $1.3 billion and 51 banking offices serving Michigan’s Lower Peninsula. Bank subsidiaries include: Firstbank – Alma; Firstbank (Mt. Pleasant); Firstbank – West Branch; Firstbank – Lakeview; Firstbank – St. Johns; Keystone Community Bank; and Firstbank – West Michigan.

This press release contains certain forward-looking statements that involve risks and uncertainties. When used in this press release the words “anticipate,” “believe,” “expect,” “potential,” “should,” and similar expressions identify forward-looking statements. Forward-looking statements include, but are not limited to, statements concerning future business growth and the expected closing date. 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/or 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.