MERCANTILE BANK CORP - Quarter Report: 2015 June (Form 10-Q)

U.S. SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 10-Q

[X] QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended June 30, 2015

[ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

For the transition period from            to            .

Commission File No. 000-26719

MERCANTILE BANK CORPORATION

(Exact name of registrant as specified in its charter)

310 Leonard Street, NW, Grand Rapids, MI 49504

(Address of principal executive offices) (Zip Code)

(616) 406-3000

(Registrant’s telephone number, including area code)

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

At August 7, 2015, there were 16,459,841 shares of common stock outstanding.

MERCANTILE BANK CORPORATION

INDEX

MERCANTILE BANK CORPORATION

PART I --- FINANCIAL INFORMATION

Item 1. Financial Statements

CONDENSED CONSOLIDATED BALANCE SHEETS

(Unaudited)

See accompanying notes to condensed consolidated financial statements.

MERCANTILE BANK CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF INCOME

(Unaudited)

See accompanying notes to condensed consolidated financial statements.

MERCANTILE BANK CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

(Unaudited)

See accompanying notes to condensed consolidated financial statements.

MERCANTILE BANK CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF

CHANGES IN SHAREHOLDERS’ EQUITY

(Unaudited)

See accompanying notes to condensed consolidated financial statements.

MERCANTILE BANK CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF

CHANGES IN SHAREHOLDERS’ EQUITY (Continued)

(Unaudited)

See accompanying notes to condensed consolidated financial statements.

MERCANTILE BANK CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(Unaudited)

See accompanying notes to condensed consolidated financial statements.

MERCANTILE BANK CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Continued)

(Unaudited)

See accompanying notes to condensed consolidated financial statements.

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

Basis of Presentation: The unaudited financial statements for the six months ended June 30, 2015 include the consolidated results of operations of Mercantile Bank Corporation and its consolidated subsidiaries. These subsidiaries include Mercantile Bank of Michigan (“our bank”) and our bank’s two subsidiaries, Mercantile Bank Real Estate Co., LLC (“our real estate company”) and Mercantile Insurance Center, Inc. (“our insurance center”). These consolidated financial statements have been prepared in accordance with the instructions for Form 10-Q and Item 303(b) of Regulation S-K and do not include all disclosures required by accounting principles generally accepted in the United States of America for a complete presentation of our financial condition and results of operations. In the opinion of management, the information reflects all adjustments (consisting only of normal recurring adjustments) which are necessary in order to make the financial statements not misleading and for a fair presentation of the results of operations for such periods. The results for the period ended June 30, 2015 should not be considered as indicative of results for a full year. For further information, refer to the consolidated financial statements and footnotes included in our annual report on Form 10-K for the year ended December 31, 2014.

We have five separate business trusts that were formed to issue trust preferred securities. Subordinated debentures were issued to the trusts in return for the proceeds raised from the issuance of the trust preferred securities. The trusts are not consolidated, but instead we report the subordinated debentures issued to the trusts as a liability.

Earnings Per Share: Basic earnings per share is based on the weighted average number of common shares and participating securities outstanding during the period. Diluted earnings per share include the dilutive effect of additional potential common shares issuable under our stock-based compensation plans and are determined using the treasury stock method. Our unvested restricted shares, which contain non-forfeitable rights to dividends whether paid or accrued (i.e., participating securities), are included in the number of shares outstanding for both basic and diluted earnings per share calculations. In the event of a net loss, our unvested restricted shares are excluded from the calculation of both basic and diluted earnings per share.

Approximately 100,000 unvested restricted shares were included in determining both basic and diluted earnings per share for the three and six months ended June 30, 2015. In addition, stock options for approximately 108,000 shares of common stock were included in determining diluted earnings per share for the three and six months ended June 30, 2015. Stock options for approximately 91,000 shares of common stock were antidilutive and not included in determining diluted earnings per share for the three and six months ended June 30, 2015.

Stock options for approximately 159,000 shares of common stock were included in determining diluted earnings per share for the three and six months ended June 30, 2014. Stock options for approximately 177,000 shares of common stock were antidilutive and not included in determining diluted earnings per share for the three and six months ended June 30, 2014.

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

Securities: Debt securities classified as held to maturity are carried at amortized cost when management has the positive intent and ability to hold them to maturity. Debt securities are classified as available for sale when they might be sold prior to maturity. Equity securities with readily determinable fair values are classified as available for sale. Securities available for sale are carried at fair value, with unrealized holding gains and losses reported in other comprehensive income, net of tax. Federal Home Loan Bank stock is carried at cost.

Interest income includes amortization of purchase premiums and accretion of discounts. Premiums and discounts on securities are amortized or accreted on the level-yield method without anticipating prepayments, except for mortgage-backed securities where prepayments are anticipated. Gains and losses on sales are recorded on the trade date and determined using the specific identification method.

Declines in the fair value of debt securities below their amortized cost that are other than temporary (“OTTI”) are reflected in earnings or other comprehensive income, as appropriate. For those debt securities whose fair value is less than their amortized cost, we consider our intent to sell the security, whether it is more likely than not that we will be required to sell the security before recovery and whether we expect to recover the entire amortized cost of the security based on our assessment of the issuer’s financial condition. In analyzing an issuer’s financial condition, we consider whether the securities are issued by the federal government or its agencies, and whether downgrades by bond rating agencies have occurred. If either of the criteria regarding intent or requirement to sell is met, the entire difference between amortized cost and fair value is recognized as impairment through earnings. For debt securities that do not meet the aforementioned criteria, the amount of impairment is split into two components as follows: 1) OTTI related to credit loss, which must be recognized in the income statement, and 2) OTTI related to other factors, such as liquidity conditions in the market or changes in market interest rates, which is recognized in other comprehensive income. The credit loss is defined as the difference between the present value of the cash flows expected to be collected and the amortized cost.

Loans: Loans that we have the intent and ability to hold for the foreseeable future or until maturity or payoff are reported at the principal balance outstanding, net of deferred loan fees and costs and an allowance for loan losses. Interest income is accrued on the unpaid principal balance. Loan origination fees, net of certain direct origination costs, are deferred and recognized in interest income using the level-yield method without anticipating prepayments.

Interest income on commercial loans and mortgage loans is discontinued at the time the loan is 90 days delinquent unless the loan is well-secured and in process of collection. Consumer and credit card loans are typically charged off no later than when they are 120 days past due. Past due status is based on the contractual terms of the loan. In all cases, loans are placed on nonaccrual or charged off at an earlier date if collection of principal and interest is considered doubtful.

All interest accrued but not received for loans placed on nonaccrual is reversed against interest income. Interest received on such loans is accounted for on the cash-basis or cost-recovery method, until qualifying for return to accrual. Loans are returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured.

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

Loans Held for Sale: Mortgage loans originated and intended for sale in the secondary market are carried at the lower of aggregate cost or market, as determined by outstanding commitments from investors. Net unrealized losses, if any, are recorded as a valuation allowance and charged to earnings. As of June 30, 2015 and December 31, 2014, we determined that the fair value of our mortgage loans held for sale approximated the recorded cost of $2.4 million and $1.6 million, respectively. Loans held for sale are reported as part of our total loans on the balance sheet.

Mortgage loans held for sale are generally sold with servicing rights retained. Gains and losses on sales of mortgage loans are based on the difference between the selling price and the carrying value of the related loan sold, which is reduced by the cost allocated to the servicing right. We generally lock in the sale price to the purchaser of the loan at the same time we make a rate commitment to the borrower. These mortgage banking activities are not designated as hedges and are carried at fair value. The net gain or loss on mortgage banking derivatives is included in the gain on sale of loans. Mortgage loans serviced for others totaled approximately $594 million as of June 30, 2015.

Mortgage Banking Activities: Mortgage loan servicing rights are recognized as assets based on the allocated value of retained servicing rights on mortgage loans sold. Mortgage loan servicing rights are carried at the lower of amortized cost or fair value and are expensed in proportion to, and over the period of, estimated net servicing revenues. Impairment is evaluated based on the fair value of the rights using groupings of the underlying mortgage loans as to interest rates. Any impairment of a grouping is reported as a valuation allowance.

Servicing fee income is recorded for fees earned for serving mortgage loans. The fees are based on a contractual percentage of the outstanding principal or a fixed amount per loan and are recorded as income when earned. Amortization of mortgage loan servicing rights is netted against mortgage loan servicing income and recorded in mortgage banking activities in the income statement.

Troubled Debt Restructurings: A loan is accounted for as a troubled debt restructuring if we, for economic or legal reasons, grant a concession to a borrower considered to be experiencing financial difficulties that we would not otherwise consider. A troubled debt restructuring may involve the receipt of assets from the debtor in partial or full satisfaction of the loan, or a modification of terms such as a reduction of the stated interest rate or balance of the loan, a reduction of accrued interest, an extension of the maturity date or renewal of the loan at a stated interest rate lower than the current market rate for a new loan with similar risk, or some combination of these concessions. Troubled debt restructurings can be in either accrual or nonaccrual status. Nonaccrual troubled debt restructurings are included in nonperforming loans. Accruing troubled debt restructurings are generally excluded from nonperforming loans as it is considered probable that all contractual principal and interest due under the restructured terms will be collected.

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

In accordance with current accounting guidance, loans modified as troubled debt restructurings are, by definition, considered to be impaired loans. Impairment for these loans is measured on a loan-by-loan basis similar to other impaired loans as described above under “Allowance for Loan Losses.” Certain loans modified as troubled debt restructurings may have been previously measured for impairment under a general allowance methodology (i.e., pooling), thus at the time the loan is modified as a troubled debt restructuring the allowance will be impacted by the difference between the results of these two measurement methodologies. Loans modified as troubled debt restructurings that subsequently default are factored into the determination of the allowance in the same manner as other defaulted loans.

Allowance for Loan Losses: The allowance for loan losses (“allowance”) is a valuation allowance for probable incurred credit losses. Loan losses are charged against the allowance when we believe the uncollectability of a loan is confirmed. Subsequent recoveries, if any, are credited to the allowance. We estimate the allowance balance required using past loan loss experience, the nature and volume of the portfolio, information about specific borrower situations and estimated collateral values, economic conditions and other factors. Allocations of the allowance may be made for specific loans, but the entire allowance is available for any loan that, in our judgment, should be charged-off.

A loan is considered to be impaired when, based on current information and events, it is probable we will be unable to collect the scheduled payments of principal and interest when due according to the contractual terms of the loan agreement. Factors considered in determining impairment include payment status, collateral value and the probability of collecting scheduled principal and interest payments when due. Loans that experience insignificant payment delays and payment shortfalls generally are not classified as impaired. We determine the significance of payment delays and payment shortfalls on a case-by-case basis, taking into consideration all of the circumstances surrounding the loan and the borrower, including the length of delay, the reasons for delay, the borrower’s prior payment record and the amount of the shortfall in relation to the principal and interest owed. Impairment is measured on a loan-by-loan basis for commercial and construction loans by either the present value of expected future cash flows discounted at the loan’s effective interest rate, the loan’s obtainable market price or the fair value of collateral if the loan is collateral dependent. Large groups of smaller balance homogeneous loans are collectively evaluated for impairment.

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

Derivatives: Derivative financial instruments are recognized as assets or liabilities at fair value. The accounting for changes in the fair value of derivatives depends on the use of the derivatives and whether the derivatives qualify for hedge accounting. Used as part of our asset and liability management to help manage interest rate risk, our derivatives have generally consisted of interest rate swap agreements that qualified for hedge accounting. In February 2012, we entered into an interest rate swap agreement that qualifies for hedge accounting. The current outstanding interest rate swap is discussed in more detail in Note 10. We do not use derivatives for trading purposes.

Changes in the fair value of derivatives that are designated, for accounting purposes, as a hedge of the variability of cash flows to be received on various loans and are effective are reported in other comprehensive income. They are later reclassified into earnings in the same periods during which the hedged transaction affects earnings and are included in the line item in which the hedged cash flows are recorded. If hedge accounting does not apply, changes in the fair value of derivatives are recognized immediately in current earnings as interest income or expense.

If designated as a hedge, we formally document the relationship between derivatives as hedged items, as well as the risk-management objective and the strategy for undertaking hedge transactions. This documentation includes linking cash flow hedges to specific assets and liabilities on the balance sheet. If designated as a hedge, we also formally assess, both at the hedge’s inception and on an ongoing basis, whether the derivative instruments that are used are highly effective in offsetting changes in cash flows of the hedged items. Ineffective hedge gains and losses are recognized immediately in current earnings as noninterest income or expense. We discontinue hedge accounting when we determine the derivative is no longer effective in offsetting changes in the cash flows of the hedged item, the derivative is settled or terminates, or treatment of the derivative as a hedge is no longer appropriate or intended.

Goodwill and Core Deposit Intangible: Goodwill results from business acquisitions and represents the excess of the purchase price over the fair value of acquired tangible assets and liabilities and identifiable intangible assets. Goodwill is assessed at least annually for impairment and any such impairment is recognized in the period identified. A more frequent assessment is performed if conditions in the market place or changes in the company’s organizational structure occur. We use a discounted income approach and a market valuation model, which compares the inherent value of our company to valuations of recent transactions in the market place to determine if our goodwill has been impaired.

The core deposit intangible that arose from the Firstbank Corporation acquisition was initially measured at fair value and is being amortized into noninterest expense over a ten-year period using the sum-of-the-years-digits methodology.

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

Adoption of New Accounting Standards: In January of 2014, the FASB issued ASU 2014-04, Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure. This ASU clarifies that an in substance repossession or foreclosure occurs, and a creditor is considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan, upon either (1) the creditor obtaining legal title to the residential real estate property upon completion of a foreclosure or (2) the borrower conveying all interest in the residential real estate property to the creditor to satisfy that loan through completion of a deed in lieu of foreclosure or through a similar legal agreement. The ASU also requires additional related interim and annual disclosures. The guidance in this ASU is effective for annual and interim periods beginning after December 15, 2014. The adoption of this ASU did not have a material effect on our financial position or results of operations.

In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers. This ASU establishes a comprehensive revenue recognition standard for virtually all industries under U.S. GAAP, including those that previously followed industry-specific guidance such as the real estate, construction and software industries. The revenue standard’s core principle is built on the contract between a vendor and a customer for the provision of goods and services. It attempts to depict the exchange of rights and obligations between the parties in the pattern of revenue recognition based on the consideration to which the vendor is entitled. To accomplish this objective, the standard requires five basic steps: i) identify the contract with the customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations in the contract, and (v) recognize revenue when (or as) the entity satisfies a performance obligation. This ASU is effective for annual and interim periods beginning after December 15, 2016 with three transition methods available – full retrospective, retrospective and cumulative effect approach. Adoption of this ASU is not expected to have a material effect on our financial position or results of operations.

In June 2014, the FASB issued ASU 2014-11, Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures. This ASU requires two accounting changes. First, repurchase-to-maturity transactions will be accounted for as secured borrowing transactions on the balance sheet, rather than sales. Second, for repurchase financing arrangements, the ASU requires separate accounting for a transfer of a financial asset executed contemporaneously with (or in contemplation of) a repurchase agreement with the same counterparty, which also will generally result in secured borrowing accounting for the repurchase agreement. The ASU also introduces new disclosures to increase transparency about the types of collateral pledged for repurchase agreements, securities lending transactions, and repurchase-to-maturity transactions that are accounted for as secured borrowings. The ASU also requires a transferor to disclose information about transactions accounted for as a sale in which the transferor retains substantially all of the exposure to the economic return on the transferred financial assets through an agreement with the transferee. The accounting changes and disclosure for certain transactions accounted for as a sale are effective for the first interim or annual period beginning after December 15, 2014. The disclosure for transactions accounted for as secured borrowings is required for annual periods beginning after December 15, 2014, and for interim periods beginning after March 15, 2015. The required disclosures under the ASU are included in Note 7. Adoption of this ASU did not have a material effect on our financial position or results of operations.

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

In August 2014, the FASB issued ASU 2014-14, Classification of Certain Government-Guaranteed Mortgage Loans Upon Foreclosure. This ASU requires that certain government-guaranteed mortgage loans, including those guaranteed by the Federal Housing Administration, be derecognized and that a separate other receivable be recognized upon foreclosure if certain conditions are met. Upon foreclosure on the loans that meet these criteria, a separate receivable should be recorded based on the amount of the loan balance expected to be recovered from the guarantor. The amendments are effective for annual periods, and interim periods within those years, beginning after December 15, 2014. The adoption of this ASU did not have a material effect on our financial position or results of operations.

We completed the merger of Firstbank Corporation (“Firstbank”), a Michigan corporation with approximately $1.5 billion in total assets and 46 branch locations, into Mercantile Bank Corporation as of June 1, 2014 (“Merger Date”). The results of operations due to the Firstbank transaction have been included in Mercantile’s financial results since the Merger Date. All of Firstbank’s common stock was converted into the right to receive one share of Mercantile common stock for each share of Firstbank common stock. The conversion of Firstbank’s common stock into Mercantile’s common stock resulted in Mercantile issuing 8,087,272 shares of its common stock. The merger provided an expanded geographic footprint for the Company and increased the size of the balance sheet.

The Firstbank transaction was accounted for using the acquisition method of accounting and accordingly, assets acquired, liabilities assumed and consideration exchanged were recorded at estimated fair value on the Merger Date. Preliminary goodwill of $49.5 million was calculated as the purchase premium after adjusting for the fair value of net assets acquired and represents the value expected from the synergies created from combining the two banking organizations as well as the economies of scale expected from combining the operations of the two companies. None of the goodwill is deductible for income tax purposes as the merger is accounted for as a tax-free exchange.

The following table provides the unaudited pro forma information for the results of operations for the three and six month periods ended June 30, 2014 as if the acquisition had occurred on January 1, 2014. These adjustments reflect the impact of certain purchase accounting fair value measurements, primarily comprised of Firstbank’s loan and deposit portfolios. We expect to achieve further operating cost savings and other business synergies as a result of the merger which are not reflected in the pro forma amounts. These unaudited pro forma results are presented for illustrative purposes only and are not intended to represent or be indicative of the actual results of operations of the combined banking organization that would have been achieved had the merger occurred at the beginning of each period presented, nor are they intended to represent or be indicative of future results of operations.

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

In most instances, determining the fair value of the acquired assets and assumed liabilities required us to estimate cash flows expected to result from those assets and liabilities and to discount those cash flows at appropriate rates of interest. The most significant of those determinations relates to the valuation of acquired loans. For such loans, the excess of cash flows expected at acquisition over the estimated fair value is recognized as interest income over the remaining lives of the loans. The difference between contractually required payments at acquisition and the cash flows expected to be collected at acquisition reflects the impact of estimated credit losses and other factors, such as prepayments. In accordance with the applicable accounting guidance for business combinations, there was no carry-over of Firstbank’s previously established allowance for loan losses.

The acquired loans were divided into loans with evidence of credit quality deterioration, which are accounted for under ASC 310-30 (“acquired impaired”), and loans that do not meet this criteria, which are accounted for under ASC 310-20 (“acquired non-impaired”). In addition, the loans are further categorized into different loan pools based primarily on the type and purpose of the loan.

We also assumed obligations under junior subordinated debentures with an aggregate balance of $36.1 million and an aggregate fair value of $21.1 million as of the Merger Date, payable to four unconsolidated trusts (Firstbank Capital Trust I, Firstbank Capital Trust II, Firstbank Capital Trust III, and Firstbank Capital Trust IV) that have issued trust preferred securities. The junior subordinated debentures are the sole assets of each trust. Interest rates on all trust preferred securities issued by the trusts are tied to the 90 Day Libor rate with spreads ranging from 127 basis points to 199 basis points, and reset quarterly. The trust preferred securities have maturity dates ranging from October, 2034 to July, 2037, and are callable by us in whole or in part quarterly. The junior subordinated debentures are unsecured obligations of Mercantile, who has guaranteed that interest payments on the junior subordinated debentures made to the trust will be distributed by the trust to the holders of the trust preferred securities. The trust preferred securities currently fully qualify as Tier 1 Capital, and under current risk-based capital guidelines, will remain fully qualified as Tier 1 Capital until maturity unless called by us at an earlier date.

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

The amortized cost and fair value of available for sale securities and the related pre-tax gross unrealized gains and losses recognized in accumulated other comprehensive income are as follows:

Securities with unrealized losses at June 30, 2015 and December 31, 2014, aggregated by investment category and length of time that individual securities have been in a continuous loss position, are as follows:

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

We evaluate securities for other-than-temporary impairment at least on a quarterly basis. Consideration is given to the length of time and the extent to which the fair value has been less than cost, the financial condition and near-term prospects of the issuer, and the intent and ability we have to retain our investment in the issuer for a period of time sufficient to allow for any anticipated recovery in fair value. For those debt securities whose fair value is less than their amortized cost basis, we also consider our intent to sell the security, whether it is more likely than not that we will be required to sell the security before recovery and if we do not expect to recover the entire amortized cost basis of the security. In analyzing an issuer’s financial condition, we may consider whether the securities are issued by the federal government or its agencies, whether downgrades by bond rating agencies have occurred and the results of reviews of the issuer’s financial condition.

At June 30, 2015, 316 debt securities and one mutual fund with fair values totaling $182.4 million have unrealized losses aggregating $3.2 million. After we considered whether the securities were issued by the federal government or its agencies and whether downgrades by bond rating agencies had occurred, we determined that unrealized losses were due to changing interest rate environments. As we do not intend to sell our debt securities before recovery of their cost basis and we believe it is more likely than not that we will not be required to sell our debt securities before recovery of the cost basis, no unrealized losses are deemed to be other-than-temporary.

The amortized cost and fair value of debt securities at June 30, 2015, by maturity, are shown in the following table. The contractual maturity is utilized for U.S. Government agency debt obligations and municipal bonds. Expected maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. Securities not due at a single maturity date, primarily mortgage-backed securities, are shown separately. Weighted average yields are also reflected, with yields for municipal securities shown at their tax equivalent yield.

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

Securities issued by the State of Michigan and all its political subdivisions had a combined amortized cost of $103.1 million and $113.1 million at June 30, 2015 and December 31, 2014, respectively, with estimated market values of $103.0 million and $113.9 million, respectively. Securities issued by all other states and their political subdivisions had a combined amortized cost of $26.6 million and $30.0 million at June 30, 2015 and December 31, 2014, respectively, with estimated market values of $27.0 million and $30.0 million, respectively. Total securities of any other specific issuer, other than the U.S. Government and its agencies and the State of Michigan and all its political subdivisions, did not exceed 10% of shareholders’ equity.

The carrying value of U.S. Government agency debt obligations and mortgage-backed securities that are pledged to secure repurchase agreements was $152.1 million and $167.6 million at June 30, 2015, and December 31, 2014, respectively. Investments in Federal Home Loan Bank stock are restricted and may only be resold or redeemed by the issuer.

Loans originated for investment are stated at their principal amount outstanding adjusted for partial charge-offs, the allowance, and net deferred loan fees and costs. Interest income on loans is accrued over the term of the loans primarily using the simple interest method based on the principal balance outstanding. Interest is not accrued on loans where collectability is uncertain. Accrued interest is presented separately in the consolidated balance sheet. Loan origination fees and certain direct costs incurred to extend credit are deferred and amortized over the term of the loan or loan commitment period as an adjustment to the related loan yield.

Acquired loans are those purchased in the Firstbank merger (See Note 2 – Business Combination for further information). These loans were recorded at estimated fair value at the Merger Date with no carryover of the related allowance. The acquired loans were segregated between those considered to be performing (“acquired non-impaired loans”) and those with evidence of credit deterioration (“acquired impaired loans”). Acquired loans are considered impaired if there is evidence of credit deterioration and if it is probable, at acquisition, all contractually required payments will not be collected. Acquired loans restructured after acquisition are not considered or reported as troubled debt restructurings if the loans evidenced credit deterioration as of the Merger Date and are accounted for in pools.

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

The fair value estimates for acquired loans are based on expected prepayments and the amount and timing of discounted expected principal, interest and other cash flows. Credit discounts representing the principal losses expected over the life of the loan are also a component of the initial fair value. In determining the Merger Date fair value of acquired impaired loans, and in subsequent accounting, we have generally aggregated acquired commercial and consumer loans into pools of loans with common risk characteristics.

The difference between the fair value of an acquired non-impaired loan and contractual amounts due at the Merger Date is accreted into income over the estimated life of the loan. Contractually required payments represent the total undiscounted amount of all uncollected principal and interest payments. Acquired non-impaired loans are placed on nonaccrual status and reported as nonperforming or past due using the same criteria applied to the originated loan portfolio.

The excess of an acquired impaired loan’s undiscounted contractually required payments over the amount of its undiscounted cash flows expected to be collected is referred to as the non-accretable difference. The non-accretable difference, which is neither accreted into income nor recorded on the consolidated balance sheet, reflects estimated future credit losses and uncollectible contractual interest expected to be incurred over the life of the acquired impaired loan. The excess cash flows expected to be collected over the carrying amount of the acquired loan is referred to as the accretable yield. This amount is accreted into interest income over the remaining life of the acquired loans or pools using the level yield method. The accretable yield is affected by changes in interest rate indices for variable rate loans, changes in prepayment speed assumptions and changes in expected principal and interest payments over the estimated lives of the acquired impaired loans.

We evaluate quarterly the remaining contractual required payments receivable and estimate cash flows expected to be collected over the lives of the impaired loans. Contractually required payments receivable may increase or decrease for a variety of reasons, for example, when the contractual terms of the loan agreement are modified, when interest rates on variable rate loans change, or when principal and/or interest payments are received. Cash flows expected to be collected on acquired impaired loans are estimated by incorporating several key assumptions similar to the initial estimate of fair value. These key assumptions include probability of default, loss given default, and the amount of actual prepayments after the Merger Date. Prepayments affect the estimated lives of loans and could change the amount of interest income, and possibly principal, expected to be collected. In re-forecasting future estimated cash flows, credit loss expectations are adjusted as necessary. The adjustments are based, in part, on actual loss severities recognized for each loan type, as well as changes in the probability of default. For periods in which estimated cash flows are not re-forecasted, the prior reporting period’s estimated cash flows are adjusted to reflect the actual cash received and credit events that transpired during the current reporting period.

Increases in expected cash flows of acquired impaired loans subsequent to the Merger Date are recognized prospectively through adjustments of the yield on the loans or pools over their remaining lives, while decreases in expected cash flows are recognized as impairment through a provision for loan losses and an increase in the allowance.

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)

Our total loans at June 30, 2015 were $2.17 billion compared to $2.09 billion at December 31, 2014, an increase of $82.6 million, or 4.0%. The components of our loan portfolio disaggregated by class of loan within the loan portfolio segments at June 30, 2015 and December 31, 2014, and the percentage change in loans from the end of 2014 to the end of the second quarter of 2015, are as follows:

(Continued)

MERCANTILE BANK CORPORATION

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(Unaudited)