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    ACCESSION NUMBER:		0001437749-21-009311
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		45
    CONFORMED PERIOD OF REPORT:	20210420
    ITEM INFORMATION:		Results of Operations and Financial Condition
    ITEM INFORMATION:		Regulation FD Disclosure
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20210420
    DATE AS OF CHANGE:		20210420

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			MERCANTILE BANK CORP
    		CENTRAL INDEX KEY:			0001042729
    		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
    		IRS NUMBER:				383360865
    		STATE OF INCORPORATION:			MI
    		FISCAL YEAR END:			1231

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    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	000-26719
    		FILM NUMBER:		21836441

    	BUSINESS ADDRESS:
    		STREET 1:		310 LEONARD STREET NW
    		CITY:			GRAND RAPIDS
    		STATE:			MI
    		ZIP:			49504
    		BUSINESS PHONE:		616 406-3000

    	MAIL ADDRESS:
    		STREET 1:		310 LEONARD STREET NW
    		CITY:			GRAND RAPIDS
    		STATE:			MI
    		ZIP:			49504
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