UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (date of earliest event reported): January 30, 2015

Mercantile Bank Corporation

(Exact name of registrant as specified in its charter)

Registrant's telephone number, including area code                616-406-3000     

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐  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.

The Board of Directors of Mercantile Bank Corporation has authorized a new program to repurchase up to $20.0 million of the Company’s common stock from time to time in open market transactions at prevailing market prices or by other means in accordance with applicable regulations of the Securities and Exchange Commission.

A press release issued by the Company announcing the program is included as Exhibit 99.1 to this Current Report on Form 8-K and incorporated into this Item 8.01 by reference.

Item 9.01     Financial Statements and Exhibits.

(d) Exhibits.

Signatures

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 hereunto duly authorized.

Date: January 30, 2015

Exhibit Index

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