Slides
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Investor Presentation October 2026
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Forward-Looking Statements This presentation contains statements or information that may constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements can be identified by words such as: “anticipates,” “intends,” “plans,” “goal,” “seeks,” “believes,” “projects,” “estimates,” “expects,” “indicates,” “strategy,” “future,” “is likely,” “may,” “should,” “will,” and variations of such words and similar references to future periods. Any such statements are based on current expectations that involve a number of risks, uncertainties and assumptions (“Future Factors”) that are difficult to predict with regard to timing, extent, likelihood and degree of occurrence. We undertake no obligation to update, amend or clarify forward-looking statements, whether as a result of new information, future events (whether anticipated or unanticipated), or otherwise. Therefore, actual results and outcomes may differ materially from the results expressed or forecasted in such forward-looking statements. Future factors include, among others, difficulties and delays in the integration of Mercantile and Eastern and achieving anticipated synergies, cost savings and other benefits from the transaction; delays, cost overruns, disruptions, or other difficulties in completing our core and digital banking system conversion, or failure to realize its anticipated benefits; adverse changes in interest rates and interest rate relationships; increasing rates of inflation and slower growth rates or recession; significant declines in the value of commercial real estate; market volatility; demand for products and services; climate impact; labor markets; the degree of competition by traditional and nontraditional financial services companies; changes in banking regulation or actions by bank regulators; changes in tax laws and other laws and regulations applicable to us; changes in prices, levies, and assessments; the impact of technological advances; potential cyber-attacks, information security breaches and other criminal activities; litigation liabilities; governmental and regulatory policy changes; the outcomes of existing or future contingencies; trends in customer behavior as well as their ability to repay loans; changes in local real estate values; damage to our reputation resulting from adverse publicity, regulatory actions, litigation, operational failures, and the failure to meet client expectations and other facts; changes in the national and local economies; unstable political and economic environments; disease outbreaks, such as the COVID-19 pandemic or similar public health threats, and measures implemented to combat them; and other risk factors described in our annual report on Form 10-K for the year ended December 31, 2025, including those disclosed from time to time in filings made by Mercantile with the Securities and Exchange Commission. Investors are cautioned not to place undue reliance on any forward-looking statements contained herein. Investor Presentation
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Company Overview
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4 Executive Management Team Investor Presentation RAYMOND REITSMA PRESIDENT AND CHIEF EXECUTIVE OFFICER Mr. Reitsma was appointed President and Chief Executive Officer of Mercantile effective June 1, 2024, and has been with the Bank for over 20 years, beginning with his initial role as a Commercial Loan Manager in 2003, including holding the title of Senior Lender for eight years and President for seven years. CHARLES CHRISTMAS EVP, CHIEF FINANCIAL OFFICER, AND TREASURER Mr. Christmas has served as Chief Financial Officer at Mercantile since 1998. Prior to joining Mercantile, Mr. Christmas was a bank examiner for the Federal Deposit Insurance Corporation. JANINA KREIDER SVP, FINANCE DIRECTOR Ms. Kreider serves as Finance Director and joined the Bank in 2021. Prior to joining Mercantile, Ms. Kreider held roles at Steelcase and credit- focused investments firms.
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5 The largest bank founded, headquartered, and serving in Michigan. Company Overview OVERVIEW • Founded in 1997 in Grand Rapids, MI. • $7.2 billion in total assets. • Acquisition of Eastern Michigan Financial Corporation closed December 31, 2025. • More than 800 employees and over 50 locations . • Offers more than 75 products and services supporting commercial, business, governmental, educational, nonprofit, treasury and personal banking needs. WE INVEST IN OUR COMMUNITIES BY: • Volunteering more than 24,000 hours supporting more than 900 organizations. • Teaching more than 300 financial wellness classes. • Donating over $1.0 million to local non-profits and fundraisers. • Employing 40+ interns each year, investing in the next generation. MB EMB (1) (1) Excludes one loan production office (66 N. Howard Ave, Croswell).
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6 Company Overview Strategic Areas of Focus CLIENT EXPERIENCE • Advance client onboarding and servicing technology • Enhance existing technology solutions • Expand sales training, tools, and resources • Deepen understanding of client needs and behaviors GROWTH • Continue growing local deposits • Expand our Southeast Michigan presence • Strengthen our business banking reputation and portfolio • Extend traditional and digital marketing reach • Continue prudent commercial loan growth • Continue evaluating complementary M&A targets PEOPLE AND CULTURE • Reinforce a culture of employee value and empowerment • Broaden and deepen employee training • Strengthen workplace engagement • Improve communication across departments • Maintain competitive compensation and benefits • Deepen our community impact EFFICIENCY • Expand data analytics and process automation • Further improve efficiency across functions • Continue exploring AI applications • Continue software investment and upgrades RISK MANAGEMENT • Maintain and strengthen our credit culture • Refine interest rate risk management and reporting • Maintain effective compliance practices • Enhance enterprise risk practices, monitoring, and reporting
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Third Quarter 2026 Financial Performance
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8 3Q26 Performance Highlights Financial Performance EARNINGS • Quarter-over-quarter (3Q26 vs 3Q25) revenue growth of over 17% with earnings partially offset by one-time costs and investments in people and technology. • EPS of $1.39 in 3Q26 vs. $1.46 in 3Q25 with EPS impacted by timing of cost savings from acquisition and non-recurring costs • 1.4% ROAA and 12.6% ROAE in 3Q26 vs. 1.5% ROAA and 14.7% ROAE in 3Q25 NET INTEREST MARGIN AND NET INTEREST INCOME • Net interest margin of 3.73% in 3Q26 vs. 3.49% in 3Q25 • Driven by lower cost of funds relating to EMB acquisition, repricing of fixed rate assets, and refinement in deposit mix COMMERCIAL LOAN PORTFOLIO • Commercial loans increased 2% annualized in 3Q26 • 9% increase from prior year third quarter end • C&I and Owner Occupied CRE combined represented 55% of the portfolio as of September 30, 2026 • Pipeline remains solid ASSET QUALITY • Nonperforming assets to total assets ratio of 0.14% at the end of 3Q26 • Net loan recoveries to average loans of 0.02% in 3Q26 DEPOSIT AND FUNDING • Continued focus on building local deposit base • Deposits increased 17% from prior year third quarter end; 6% in 3Q26 • Loan-to-deposit ratio at 88% at the end of 3Q26 vs. 96% at the end of 3Q25 CAPITAL • CET1 capital ratio of 11.4% at the end of 3Q26 vs. 11.3% at the end of 3Q25 • Total risk-based capital ratio of 14.6% at the end of 3Q26 vs. 14.9% at the end of 3Q25 • Tangible book value per share of $37.81 at the end of 3Q26 vs. $37.41 at the end of 3Q25
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9 3Q26 Performance Highlights This is a year of investments in people and technology. Solid margin improvement continues, while investments in the business drive higher expenses and lower near-term earnings. Financial Performance $24mm $23mm $23mm $26mm $24mm $10mm $15mm $20mm $25mm $30mm 3rd Qtr 2025 4th Qtr 2025 1st Qtr 2026 2nd Qtr 2026 3rd Qtr 2026 Net income $1.46 $1.40 $1.32 $1.50 $1.39 $1.20 $1.30 $1.40 $1.50 $1.60 3rd Qtr 2025 4th Qtr 2025 1st Qtr 2026 2nd Qtr 2026 3rd Qtr 2026 Diluted earnings per share 1.5% 1.4% 1.4% 1.5% 1.4% 0.00% 0.50% 1.00% 1.50% 2.00% 3rd Qtr 2025 4th Qtr 2025 1st Qtr 2026 2nd Qtr 2026 3rd Qtr 2026 Return on average assets 14.7% 13.5% 12.5% 14.0% 12.6% 0.00% 5.00% 10.00% 15.00% 20.00% 3rd Qtr 2025 4th Qtr 2025 1st Qtr 2026 2nd Qtr 2026 3rd Qtr 2026 Return on average equity 3.49% 3.43% 3.55% 3.59% 3.73% 3.20% 3.40% 3.60% 3.80% 3rd Qtr 2025 4th Qtr 2025 1st Qtr 2026 2nd Qtr 2026 3rd Qtr 2026 Net interest margin (fully tax-equivalent) 55.7% 59.2% 62.3% 57.3% 59.5% 50% 55% 60% 65% 3rd Qtr 2025 4th Qtr 2025 1st Qtr 2026 2nd Qtr 2026 3rd Qtr 2026 Efficiency ratio
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10 Historical Trends and Shareholder Value Strong Track Record of Delivering Shareholder Value Solid Earnings and Balance Sheet Growth Trends Financial Performance 4.4 5.3 4.9 5.4 6.1 6.8 $0 $2 $4 $6 $8 2020 2021 2022202320242025 Billions Total Assets 9.0% CAGR 3.2 3.5 3.9 4.3 4.6 4.8 $0 $1 $2 $3 $4 $5 $6 2020 2021 2022202320242025 Billions Total Loans 8.6% CAGR 3.4 4.1 3.7 3.9 4.7 5.3 $0 $1 $2 $3 $4 $5 $6 2020 2021 2022202320242025 Billions Total Deposits 9.2% CAGR 2.71 3.69 3.85 5.13 4.93 5.47 $0 $1 $2 $3 $4 $5 $6 2020 2021 2022 2023 2024 2025 EPS 15.1% CAGR 23.86 25.61 24.47 29.31 33.14 36.78 $0 $10 $20 $30 $40 2020 2021 2022 2023 2024 2025 TBVPS 9.0% CAGR 1.12 1.18 1.26 1.34 1.42 1.50 $0.0 $0.2 $0.4 $0.6 $0.8 $1.0 $1.2 $1.4 $1.6 2020 2021 2022 2023 2024 2025 Cash Dividends 6.0% CAGR
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11 Expanding margin and net interest income in a dynamic interest rate environment Financial Performance Solid net interest margin • Proactive balance sheet management strategies that support margin stabilization include: o Matched funding fixed rate commercial loans and deposit mix strategies/management o Commercial loan back-to-back interest rate swap program o Laddered maturities in investment portfolio and purchases of heavily discounted callable agency bonds o Refinement of deposit base o Acquisition of EMB provided low- cost deposits $52 $51 $56 $57 $61 3.49% 3.43% 3.55% 3.59% 3.73% 5.74% 5.52% 5.42% 5.42% 5.52% 2.25% 2.09% 1.87% 1.83% 1.79% 4.35% 4.01% 3.68% 3.63% 3.68% $20 $25 $30 $35 $40 $45 $50 $55 $60 $65 0.0% 1.0% 2.0% 3.0% 4.0% 5.0% 6.0% 7.0% 8.0% 3rd Qtr 2025 4th Qtr 2025 1st Qtr 2026 2nd Qtr 2026 3rd Qtr 2026 In millions Net Interest Income Net interest margin (fully tax-equivalent) Earning Asset Yield Cost of Funds SOFR 90-Day Average Upcoming Repricing Opportunities as of September 30, 2026 Fixed Rate CRE Agency Bonds Total Amount Average Rate Total Amount Average Rate Remainder of 2026 $ 58,000,000 4.92% $ 16,000,000 1.53% 2027 $ 191,500,000 4.91% $ 100,000,000 2.51%
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12 Net Interest Income Solid net interest income in a dynamic interest rate environment • Despite changing interest rate environment, net interest income continues to be solid driven by: • Quarter-over-quarter growth in average assets • Active match funding initiatives • Higher yield on investments as fixed rate securities reprice • Repricing of fixed rate loans • Repricing of time deposits • Stable noninterest bearing deposits • EMB acquisition Financial Performance $75 $71 $72 $73 $77 $11 $11 $14 $13 $14 $5.9 $5.9 $6.4 $6.4 $6.5 $0B $1B $2B $3B $4B $5B $6B $7B $0mm $10mm $20mm $30mm $40mm $50mm $60mm $70mm $80mm $90mm 3Q25 4Q25 1Q26 2Q26 3Q26 Assets Interest Income Interest on Securities and Interest Earning Deposits Interest on Loans, including fees Average Earning Assets $27 $25 $23 $23 $23 $7 $6 $6 $6 $6 $3.6 $3.6 $4.0 $4.0 $4.0 $0B $1B $1B $2B $2B $3B $3B $4B $4B $0mm $5mm $10mm $15mm $20mm $25mm $30mm $35mm $40mm $45mm 3Q25 4Q25 1Q26 2Q26 3Q26 Deposits Expense Interest on Deposits Other Interest Expense Avg. Interest-Bearing Deposits 25% 25% 25% 27% 26% 20% 24% 25% 24% 26% 51% 48% 49% 49% 48% 4% 3% 1% 0.4% 0.4% 0.0% 20.0% 40.0% 60.0% 80.0% 100.0% Sep-25 Dec-25 Mar-26 Jun-26 Sep-26 % of Total Deposits Non-interest bearing deposits Lower-cost deposits Higher-cost deposits Brokered deposits Change in asset mix as on balance sheet liquidity grows Costs stable as deposit balances grow Significant low/no cost deposits
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13 Interest Rate Model • Identifies that balance sheet structure supports stable net interest income across pro forma rate environments • Purchases of highly discounted callable agency bonds provide additional protection in a down rate environment • Matched funding fixed rate commercial loans, deposit mix strategies, and commercial loan back-to-back interest rate swap program mitigate the impact of rate changes Financial Performance Reflects a gradual one-year parallel change in interest rates; simulation results as of September 30, 2026 -3.7% -7.7% -5.8% -2.9% 2.7% 5.4% 8.0% -50% -40% -30% -20% -10% 0% 10% 20% 30% 40% 50% ($100mm) ($80mm) ($60mm) ($40mm) ($20mm) $0mm $20mm $40mm $60mm $80mm $100mm -400 bp -300 bp -200 bp -100 bp +100 bp +200 bp +300 bp Projected $ change in NII Projected % change in NII
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14 Financial Performance Asset Quality Asset quality measures remain strong • Reflects ongoing commitment to soundly and vigilantly underwrite and administer loans and strength of borrowers *Reflects period ends. ($ in thousands) 3rd Qtr 2025 4th Qtr 2025 1st Qtr 2026 2nd Qtr 2026 3rd Qtr 2026 Gross loan charge-offs $ 200 2,800 0 0 0 Recoveries $ 700 200 400 500 300 Net loan charge-offs (recoveries) $ (500) 2,600 (400) (500) (300) Net loan charge-offs (recoveries) to average loans (0.05%) 0.23% (0.03%) (0.04%) (0.02%) Provision for credit losses $ 200 (700) (1,800) (1,800) 700 Allowance for credit losses $ 59,100 58,200 56,700 55,400 56,400 Allowance to loans 1.28% 1.21% 1.18% 1.13% 1.14% Nonperforming loans $ 9,800 7,900 7,500 5,800 9,700 Other real estate/repossessed assets $ 0 0 0 0 100 Nonperforming loans to total loans 0.21% 0.16% 0.16% 0.12% 0.20% Nonperforming assets to total assets 0.16% 0.12% 0.11% 0.09% 0.14% 0.07% 0.20% 0.08% 0.12% 0.16% 0.20% 0.00% 0.50% 1.00% 2021 2022 2023 2024 2025 3Q 2026 Nonperforming Loans/Total Loans Historical Nonperforming Loans to Total Loans* Quarterly Asset Quality Metrics
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15 Loan-to-Deposit Ratio* • Multi-year strategic initiative to reduce loan-to-deposit ratio • Reduced to 88% from 96% over last twelve months Financial Performance *Reflects end of quarter balances 95.9% 91.2% 88.9% 92.8% 88.3% $3,000 $3,500 $4,000 $4,500 $5,000 $5,500 $6,000 85% 90% 95% 100% 3Q25 4Q25 1Q26 2Q26 3Q26 (In millions) Loan to Deposit Ratio Total Loans Total Deposits
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16 Loan Growth Financial Performance Consistent Fundings • Commercial loan focused • Solid historical growth • Top tier asset quality • Third quarter 2026 loan balance increased but impacted by late quarter paydown activity and timing • Pipeline remains solid as shown by an increase in commitments Quarter End Core Commercial Loan Growth Trends 1.1 1.2 1.3 1.3 1.4 1.5 0.0 0.1 0.1 0.1 0.1 0.10.6 0.6 0.7 0.7 0.8 0.8 1.0 1.0 1.0 1.1 1.1 1.20.2 0.3 0.3 0.5 0.5 0.5 0.5 0.8 0.9 0.9 0.9 0.9 $0.0B $1.0B $2.0B $3.0B $4.0B $5.0B $6.0B 2021 2022 2023 2024 2025 3Q 2026 Commercial & industrial Land development & construction Owner occupied comm'l R/E Non-owner occupied comm'l R/E Multi-family & residential rental Total retail Total Loan Portfolio Growth Trends (reflects year end and quarter end balances) $3.8B $3.9B $3.9B $4.1B $4.1B $3.5B $3.6B $3.7B $3.8B $3.9B $4.0B $4.1B $4.2B 3rd Qtr 4th Qtr 1st Qtr 2nd Qtr 3rd Qtr 2025 2025 2026 2026 2026 Total Commercial Quarter End Balance Total Commercial Average Quarterly Balance
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17 Deposits and Sweep Accounts* Financial Performance • Continued refinement of deposit base • 17% growth in deposits over trailing twelve months driven both by the acquisition of EMB and organic deposit growth • 6% growth in total deposits in the third quarter of 2026 partially driven by seasonal increases in public funds • 8% growth in low and no cost deposits in the third quarter of 2026 *As of September 30, 2026 $0.0B $1.0B $2.0B $3.0B $4.0B $5.0B $6.0B $7.0B 2Q25 3Q25 4Q25 1Q26 2Q26 3Q26 Money Market Noninterest-Bearing Checking Interest-Bearing Checking Local Time $100,000 & Over Savings Local Time Under $100,000 Sweep Accounts Brokered Deposits
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18 Deposit Balances* Financial Performance Deposits comprised primarily of business accounts *As of September 30, 2026, excludes brokered deposits ($ in thousands) September 30, 2026 September 30, 2025 Personal Business Personal Business Noninterest-Bearing Checking $ 236,200 1,210,100 186,800 996,000 Interest Checking $ 254,600 880,300 171,200 590,600 Savings $ 269,500 55,800 182,300 32,600 Money Market $ 504,400 1,396,000 459,100 1,206,600 Certificates of Deposit $ 522,200 263,000 535,500 272,300 Total Deposits $ 1,786,900 3,805,200 1,534,900 3,098,100 Personal 32%Business & Public Funds 68%
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19 Large Depositors (Includes Sweep Account Balances) Financial Performance Large Depositors (Current) • Depositors with over $5 million as of September 30, 2026 Business/Individual – 72 relationships aggregating $1.7 billion Governmental – 33 relationships aggregating $0.3 billion Total – 105 relationships aggregating $2.0 billion • Depositors with over $5 million as of September 30, 2021 (5 years ago), consisted of 72 relationships aggregating $1.1 billion • Most of those relationships remain and have grown balances Aggregate Balance of the 53 Depositors ($ millions) $1,018 $1,175 $900 $950 $1,000 $1,050 $1,100 $1,150 $1,200 September 30, 2021 September 30, 2026 53 of the 72 relationships still maintain deposits over $5 million as of September 30, 2026 • Our large depositor base has grown, anchored by longstanding, “sticky” relationships • Most large depositor relationships from five years ago continue to maintain sizeable balances, with balances growing alongside their business success Large Depositors (Historic View)
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20 Noninterest Income Financial Performance $0mm $2mm $4mm $6mm $8mm $10mm $12mm 3Q25 4Q25 1Q26 2Q26 3Q26 Service charges on accounts (+33%) Payroll services (+3%) Mortgage banking income (+10%) Credit and debit card income (+23%) Interest rate swap income (+105%) Earnings on bank owned life insurance (-8%) Other income (+6%) Stable fee income: • Treasury management and credit card income increase driven by new commercial client acquisitions, effective marketing endeavors, and usage • Growth in other categories, including mortgage banking income, swap fee income and payroll services (%) Reflects 3Q 2026 compared to 3Q 2025
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21 Mortgage Loan Activity Financial Performance Stable income and solid originations • Solid originations in 3Q26 with a greater share retained 108,000 86,000 68,800 126,800 117,600 28,800 55,500 59,200 32,300 24,800 $0 $20,000 $40,000 $60,000 $80,000 $100,000 $120,000 $140,000 $160,000 $180,000 3rd Qtr 2025 4th Qtr 2025 1st Qtr 2026 2nd Qtr 2026 3rd Qtr 2026 (In thousands) Purchase mortgage loans originated Refinance mortgage loans originated MORTGAGE LOAN ORIGINATIONS MORTGAGE LOAN SALES 111,300 116,900 105,900 107,400 92,600 3,500 3,400 3,000 3,200 3,200 $2,000 $2,200 $2,400 $2,600 $2,800 $3,000 $3,200 $3,400 $3,600 $0 $20,000 $40,000 $60,000 $80,000 $100,000 $120,000 $140,000 $160,000 $180,000 3rd Qtr 2025 4th Qtr 2025 1st Qtr 2026 2nd Qtr 2026 3rd Qtr 2026 Income on Sale of Mortgage Loans (in thousands) Loans originated with intent to sell (in thousands) Total saleable mortgage loans Income on sale of mortgage loans
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22 Noninterest Expense Financial Performance Investments in People and Technology to better position for future growth • Investments in people include additional costs related to talent acquisition in SE Michigan, higher bonus accrual related to performance and employee retention, and training and development expenses • Investments in technology associated with core conversion and technology updates 56% 59% 62% 57% 60% 0% 10% 20% 30% 40% 50% 60% 70% $0mm $10mm $20mm $30mm $40mm $50mm 3Q25 4Q25 1Q26 2Q26 3Q26 Salaries and benefits (+27%) Occupancy (+9%) Furniture and equipment (+20%) Data processing costs (+22%) Core conversion costs (nm) Core deposit intangible amortization (nm) Acquisition costs (-74%) Other expense (+15%) Efficiency ratio (%) Reflects 3Q2026 compared to 3Q2025 2.2% 2.3% 2.5% 2.3% 2.5% 1.9% 2.0% 2.1% 2.2% 2.3% 2.4% 2.5% 2.6% 3Q25 4Q25 1Q26 2Q26 3Q26 Non-core - Noninterest expense to average assets (annualized) Core - Noninterest expense to average assets (annualized) Noninterest expense to average assets (annualized)
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23 Funding sources designed to match asset repricing characteristics* Floating rate: • Shorten balance sheet duration • Align with funding sources (of which a proportional amount has short durations and floating rates) to mitigate interest rate risk Fixed rate: • Match funded with fixed rate liabilities • Fixed-rate loans and securities provide a natural hedge in a declining-rate environment *As of September 30, 2026 Financial Performance Variable Rate Loans: 81% Fixed Rate Loans: 19% Total Loan Portfolio Rate Type Total Variable Rate Assets and Funding Sources $0.0B $1.0B $2.0B $3.0B $4.0B $5.0B $6.0B Floating Rate Assets Non-Time Funding Sources Interest-Earning Deposits Variable Rate Retail Loans Variable Rate Commercial Loans Sweep Accounts Non-Time Non-Interest Bearing Deposits Non-Time Interest Bearing Deposits $0.0B $0.5B $1.0B $1.5B $2.0B $2.5B $3.0B Commercial Commercial Retail Retail Variable Rate Loans Fixed Rate Loans Variable Rate Loans Fixed Rate Loans 0 – 3 Months 3 - 12 Months 1 – 5 Years Over 5 Years Total Loan Portfolio Repricing Breakdown $0.0B $1.0B $2.0B $3.0B $4.0B $5.0B Fixed Rate Assets Time Funding Sources Fixed Rate Securities Fixed Rate Retail Loans Fixed Rate Commercial Loans FHLBI Advances Time Deposits Total Fixed Rate Assets and Funding Sources
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24 Investment Portfolio Financial Performance • Net unrealized losses (before tax) equaled $78 million (or 7% of total securities book value) as of September 30, 2026 • Investment portfolio mix remains relatively unchanged, dominated by U.S Agency bonds • Continue to build the U.S Agency portfolio as part of the strategy to reduce loan to deposit ratio and mitigate interest rate risk • Increased portfolio yield given higher rate environment • Laddered maturities but concentration on bond purchases with maturities in 3-5 years ($100mm) $0mm $100mm $200mm $300mm $400mm $500mm $600mm $700mm $800mm As of September 30, 2026 Unrealized Losses Unrealized Gains Amortized Cost Fair Value ($100mm) $0mm $100mm $200mm $300mm $400mm $500mm $600mm $700mm $800mm As of December 31, 2025 Total Investment Portfolio Composition U.S. Agency Bond Segment Profile 2.51% 2.94% 3.71% 0.00% 0.50% 1.00% 1.50% 2.00% 2.50% 3.00% 3.50% 4.00% $0mm $50mm $100mm $150mm $200mm $250mm $300mm $350mm $400mm $450mm $500mm One year or less Over one through five years Over five through ten years Over ten years Amortized Cost Maturity Schedule* Amortized Cost Average Yield *As of September 30, 2026 Segment Growth 2.50% 2.60% 2.70% 2.80% 2.90% 3.00% 3.10% 3.20% ($100mm) $0mm $100mm $200mm $300mm $400mm $500mm $600mm $700mm $800mm 9/30/25 12/31/25 3/31/26 6/30/269/30/26 Book Value ($) Net Unrealized Loss ($) Average Yield (%)
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25 Capital Ratios Financial Performance Both of Mercantile Bank Corp’s subsidiaries, Mercantile Bank and Eastern Michigan Bank, have regulatory capital levels in excess of the amounts necessary to be categorized as “well capitalized.” Subsidiary Banks Total Risk Based Capital Ratios: • Mercantile Bank - 13.4% • Eastern Michigan Bank – 23.9% 0.00% 2.00% 4.00% 6.00% 8.00% 10.00% 12.00% 14.00% 16.00% 3rd Qtr 2025 4th Qtr 2025 1st Qtr 2026 2nd Qtr 2026 3rd Qtr 2026 Mercantile Bank Corporation Consolidated Capital Ratios Tier 1 leverage capital ratio Common equity risk-based capital ratio Tier 1 risk-based capital ratio Total risk-based capital ratio
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26 Sources of Liquidity Upward trend in liquidity sources driven by organic growth and the acquisition of EMB Financial Performance Availability ($ in thousands) Source December 31, 2025 September 30, 2026 Unsecured Federal Funds Line of Credit $ 50,000 50,000 FHLB of Indianapolis Advance Program $ 777,000 929,000 Unpledged Investments $ 491,000 760,000 Federal Reserve Discount Window $ 157,000 140,000 Total 1,475,000 1,879,000
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27 Financial Performance 4th QUARTER Loan Growth (annualized) 5.00%-7.00% Net Interest Margin 3.75%-3.85% Fee Income $10.0MM-$11.0MM Overhead Costs1 $42.0MM-$43.0MM Federal Tax Rate2 17% PERFORMANCE METRICS PRIME / SOFR RATES • No rate changes Thoughts on 2026 1. Excludes anticipated non-recurring costs associated with core conversion 2. Reflects expected transferable energy tax credit acquisitions
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Strong Credit Culture Diversified Lending Loan Portfolio Characteristics
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29 Loan Portfolio Characteristics *As of September 30, 2026 RETAIL LOANS 1 – 4 Family Mortgages $ 763,700 16% Other Consumer $ 118,400 2% Total Retail Loans $ 882,100 18% TOTAL LOANS $ 4,952,900 100% ($ in thousands) Balance Percentage COMMERCIAL LOANS Commercial and Industrial $ 1,499,100 30% Real Estate – Non-Owner Occupied $ 1,159,700 24% Real Estate – Owner Occupied $ 757,300 15% Real Estate – Multi-Family & Residential Rental $ 542,100 11% Real Estate – Land Development & Residential Construction $ 112,600 2% Total Commercial Loans $ 4,070,800 82% Total Loans*
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30 Asset Quality Metrics Quarter Trends ($ in thousands) • Continued strong asset quality metrics • 14 basis points nonperforming assets to total assets as of September 30, 2026 Loan Portfolio Characteristics 9/30/25 12/31/25 3/31/26 6/30/26 9/30/26 Net loan charge-offs (recoveries) $ (500) 2,600 (400) (500) (300) Net loan charge-offs (recoveries) to average loans (annualized) (0.05%) 0.23% (0.03%) (0.04%) (0.02%) Allowance to loans 1.28% 1.21% 1.18% 1.13% 1.14% Nonperforming loans to total loans 0.21% 0.16% 0.16% 0.12% 0.20% Nonperforming assets to total assets 0.16% 0.12% 0.11% 0.09% 0.14%
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31 Lending Commitments ($ in millions) *Commitments to make loans generally reflect our binding obligations to existing and prospective commercial customers to extend credit, including line of credit facilities secured by accounts receivable and inventory, and term debt secured by either real estate or equipment. Loan Portfolio Characteristics 9/30/25 12/31/25 3/31/26 6/30/26 9/30/26 CONSTRUCTION LOANS Commercial $ 216 237 240 236 266 Residential $ 37 34 32 47 44 COMMITMENTS TO MAKE LOANS* $ 133 205 289 224 279 TOTAL $ 386 476 561 507 589
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32 Loan Portfolio Characteristics 2. As of September 30, 2026 Composition – Commercial Loans 1,2 Internal Credit Risk Grade Groupings Commercial & Industrial Commercial Vacant Land, Land Dev., & Residential Construction Commercial Real Estate – Owner Occupied Commercial Real Estate – Non-Owner Occupied Commercial Real Estate – Multi-Family & Residential Rental Grades 1-4 $ 725.7 56.3 427.0 559.3 169.2 Grades 5-7 $ 755.8 54.2 323.1 600.4 372.9 Grades 8-9 $ 17.6 2.1 7.2 - - Total Commercial $ 1,499.1 112.6 757.3 1,159.7 542.1 CREDIT RISK PROFILE BY INTERNAL CREDIT RISK GRADES ($ in millions) Real Estate, Rental & Leasing 39% Agriculture, Oil & Gas Extraction & Utilities 0% Services 18% Construction 7% Manufacturing 18% Wholesale Trade 6% Retail Trade 6% Transportation & Warehousing 2% Information <1% Finance & Insurance 3% Commercial & Industrial 37% Commercial Vacant Land, Land Development & Residential Construction 3% Commercial Real Estate - Owner Occupied 19% Commercial Real Estate - Non- Owner Occupied 28% Commercial Real Estate - Multi- Family & Residential Rental 13% 1. Private credit exposure represents 2% of commercial loan balances
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33 Rate Type – Commercial Loans* ($ in millions) Strong Credit Culture *As of September 30, 2026 Balance Floating Rate Commercial Loans $ 3,267,100 Fixed Rate Commercial Loans $ 803,700 Total Commercial Loans $ 4,070,800 RATE TYPE BREAKDOWN 80% 20% Floating Rate Commercial Loans Fixed Rate Commercial Loans
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34 Past Due Loans Loan Portfolio Characteristics Commercial and Retail Past Due Loans* ($ in millions) *As of September 30, 2026. Excludes current non-accrual loans. 30–59 Days Past Due 60–89 Days Past Due > 89 Days Past Due Total Past Due Current Total Loans Recorded Balance > 89 Days & Accruing Commercial and Industrial $ – – – – 1,499.1 1,499.1 – Vacant Land, Land Development, Residential Construction $ - – - - 112.6 112.6 – Real Estate – Owner Occupied $ - 0.1 0.3 0.4 756.9 757.3 – Real Estate – Non-Owner Occupied $ – – – – 1,159.7 1,159.7 – Real Estate – Multi-Family and Residential Rental $ – – – – 542.1 542.1 – Total Commercial $ – 0.1 0.3 0.4 4,070.4 4,070.8 – 1–4 Family Mortgages $ 0.2 0.5 - 0.7 763.0 763.7 – Other Consumer Loans $ 0.3 – – 0.3 118.1 118.4 – Total Retail $ 0.5 0.5 0.0 1.0 881.1 882.1 – Total Past Due Loans $ 0.5 0.6 0.3 1.4 4,951.5 4,952.9 –
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35 Loan Portfolio Characteristics *As of September 30, 2026 $0.0 $1.0 $2.0 $3.0 $4.0 $5.0 $6.0 $7.0 $8.0 Millions 30-89 Days Past Due 90 Days & Over Past Due Over 89 Days Past Due & Accruing Past Due Loans 3 bps* as % of Total Loans
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36 FDIC Commercial Real Estate Lending Concentration Guideline for Mercantile Bank Loan Portfolio Characteristics Commercial Real Estate Loans / Total Regulatory Capital Generally not to exceed 300% 200% 210% 220% 230% 240% 250% 260% 270% 280% 290% 300% 9/30/20266/30/20263/31/202612/31/20259/30/2025
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37 Non-Owner Occupied Commercial Real Estate Lending* Loan Portfolio Characteristics • 100% of office NOO CRE is located in Michigan • 33% of office is medical • Only one nonperforming NOO CRE loan relationship over past five years *As of September 30, 2026 **Retail is defined using S&P GICS classifications for the Retailing Industry, in addition to restaurants and NOO-CRE with direct exposure to multi use retailing businesses. 8% 5% 5% 4% 1% 1% Current NOO CRE Composition % of Total Loans Industrial Retail Office Hotel Assisted Living Other Remainder of Total Loans ($ in thousands) Balance % of NOO CRE % of Total Loans Industrial $ 375,400 32% 8% Retail** $ 260,700 23% 5% Office $ 250,300 22% 5% Hotel $ 175,500 15% 4% Assisted Living $ 59,900 5% 1% Other $ 37,900 3% 1% Total $ 1,159,700 100% 24% $0 $1,000 $2,000 $3,000 $4,000 $5,000 $6,000 Historical NonPerforming NOO CRE (ending balance, $ in thousands) NonPerforming NOO CRE ($ in thousands)