Mercantile Bank Corporation

Item 1A. Risk Factors.

When evaluating the risk of an investment in our common stock, potential investors should carefully consider the risk factors appearing in Part I, Item 1A, Risk Factors, of our Annual Report on Form 10-K for the year ended December 31, 2024.

On July 22, 2025, we announced that Mercantile Bank Corporation ("Mercantile") had entered into a definitive merger agreement (Merger Agreement) with Eastern Michigan Financial Corporation (Eastern) pursuant to which Mercantile will acquire Eastern in a stock and cash transaction (the Merger). There ha following represents material changes in our risk factors from the risk factors set forth in our Annual Report on Form 10-K.

The Merger may not be consummated, which could have been no material chanan adverse impact on our business and on the value of our common stock.

We expect the Merger to close during the fourth quarter of 2025, but the Merger is subject to a number of closing conditions. Satisfaction of many of these conditions is beyond our control. If these conditions are not satisfied or waived, the Merger will not be completed. Certain of the conditions that remain to be satisfied include, but are not limited to:

Additionally, we may become subject to litiges iation related to the Merger. As a result, the Merger may not close as scheduled, or at all.

Either Eastern our risk factor Mercantile may terminate the Merger Agreement under certain circumstances. Failure to complete the Merger or any delays in completing the Merger on the terms and timing we expect could have an adverse impact on our future business, operations and results of operations including, but not limited to:

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MERCANTILE BANK CORPORATION

The Mers from those previously disclosger may be more difficult, costly or time consuming than expected, and we may fail to realize the anticipated benefits of the Merger.

The success of the Merger will depend on, among other things, our ability to integrate Eastern into our business in a manner that facilitates growth opportunities and achieves the anticipated benefits of the Merger. If we are not able to successfully achieve these objectives, the anticipated benefits of the Merger may not be realized fully or at all or may take longer to realize than expected. In addition, the actual cost savings and anticipated in our annual report on Form 10-K for tbenefits of the Merger could be less than anticipated, and integration may result in additional unforeseen expenses.

There is a significant degree of difficulty inherent in the process of integrating an acquisition, including challenges consolidating certain operations and functions (including regulatory functions), integrating technologies, organizations, procedures, policies and operations, addressing differences in the business cultures of Mercantile and Eastern and retaining key personnel. The integration will be complex and time consuming and may involve delays or additional and unforeseen expenses. The integration process and other disruptions resulting from the Merger may also disrupt our ongoing business. Any failure to successfully or cost-effectively integrate Eastern following the closing of the Merger as well as any delays encountered in the year ended December 31, 2024.

integration process, could have an adverse effect on the revenues, levels of expenses and operating results of the combined company following the completion of the Merger, which may adversely affect the value of the common stock of the combined company following the completion of the Merger.

Mercantile and Eastern will be subject to various uncertainties while the Merger is pending that could adversely affect our financial results or the anticipated benefits of the Merger.

Uncertainty about the effect of the Merger on counterparties to contracts, employees and other parties may have an adverse effect on us or the anticipated benefits of the Merger. These uncertainties could cause contract counterparties and others who deal with us or Eastern to seek to change existing business relationships with us or Eastern, and may impact our and Easterns ability to attract, retain and motivate key personnel until the Merger is completed and for a period of time thereafter.

The pursuit of the Merger and the preparation for the integration of the two companies may place a significant burden on management and internal resources. Any significant diversion of management attention away from ongoing business and any difficulties encountered in the transition and integration process could affect our financial results prior to and/or following the completion of the Merger and could limit us from pursuing attractive business opportunities and making other changes to our business prior to completion of the Merger or termination of the Merger Agreement.

We expect to incur substantial transaction costs in connection with the Merger.

We expect to incur a significant amount of non-recurring expenses in connection with the Merger, including investment banking, legal, accounting, consulting and other expenses. In general, these expenses are payable by us whether or not the Merger is completed. Additional unanticipated costs may be incurred following consummation of the Merger in the course of the integration of our businesses and the business of Eastern. We cannot be certain that the elimination of duplicative costs or the realization of other efficiencies related to the integration of the two businesses will offset the transaction and integration costs in the near term, or at all.

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MERCANTILE BANK CORPORATION