Form 8-K

8-K — ISABELLA BANK CORP

Accession: 0000842517-26-000095

Filed: 2026-04-23

Period: 2026-04-23

CIK: 0000842517

SIC: 6022 (STATE COMMERCIAL BANKS)

Item: Results of Operations and Financial Condition

Item: Financial Statements and Exhibits

Documents

8-K — isba-20260423.htm (Primary)

EX-99.1 (earningsrelease_20260331xe.htm)

GRAPHIC — ISBA LOGO (logoa.jpg)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K

8-K (Primary)

Filename: isba-20260423.htm · Sequence: 1

isba-20260423

0000842517false00008425172026-04-232026-04-23

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): April 23, 2026

ISABELLA BANK CORPORATION

(Exact name of registrant as specified in its charter)

Michigan 000-18415 38-2830092

(State or other jurisdiction

of incorporation) (Commission

File Number) (IRS Employer

Identification No.)

401 North Main Street Mt. Pleasant Michigan 48858-1649

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (989) 772-9471

Not Applicable

(Former name or former address, if changed since last report.)

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:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule l4a-12 under the Exchange Act (17 CFR 240.l4a-l2)

☐ Pre-commencement communications pursuant to Rule l4d-2(b) under the Exchange Act (17 CFR 240.l4d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.l3e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading

Symbol(s) Name of each exchange on which registered

Common stock, no par value per share ISBA

The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Section 2 - Financial Information

Item 2.02 Results of Operations and Financial Condition.

On April 23, 2026, Isabella Bank Corporation issued a press release announcing its financial results for the quarter ended March 31, 2026.

A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

In accordance with General Instruction B.2 of Form 8-K, the information in Item 2.02 of this Current Report on Form 8-K, including Exhibit 99.1 furnished herewith, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), or otherwise subject to the liabilities of that section, nor will any of such information be deemed incorporated by reference into any filing made by the registrant under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such filing or document.

Section 9 - Financial Statements and Exhibits

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits:

Exhibit

No. Description

99.1

Press release issued by Isabella Bank Corporation, dated April 23, 2026

104 Cover page interactive data file - the cover page XBRL tags are embedded within the inline XBRL document

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.

ISABELLA BANK CORPORATION

Dated: April 23, 2026 By: /s/ Gerald J. Ritzert

Gerald J. Ritzert, Chief Financial Officer

EX-99.1

Filename: earningsrelease_20260331xe.htm · Sequence: 2

Document

Exhibit 99.1

Isabella Bank Corporation Reports Strong First Quarter 2026 Earnings

MT. PLEASANT, MICHIGAN — April 23, 2026 — Isabella Bank Corporation (Nasdaq: ISBA) (“Isabella” or the “Company”) reported net income of $5.0 million, or $0.68 per diluted share, for the first quarter 2026 compared to $3.9 million, or $0.53 per diluted share, for the first quarter 2025.

FIRST QUARTER 2026 HIGHLIGHTS

•Loans, excluding advances to mortgage brokers, grew $27.2 million

•Total deposits increased $40.2 million

•Net income grew 26% compared to first quarter 2025

•Net interest margin ("NIM") improved to 3.33%, up from 3.06% in first quarter 2025

•Credit quality remained strong, with a ratio of nonperforming loans to total loans of 0.28% at March 31, 2026

“Isabella Bank Corporation delivered strong results in the first quarter, driven by loan and deposit growth across our markets," said CEO Jerome Schwind. "Initiatives implemented over the past year continue to drive noninterest income. Our initiatives this year remain focused on our commitment to provide products and services that attract new customers while continuing to fully support our current customers," he added.

"We are pleased with our stock performance after uplisting to the Nasdaq in May 2025. As expected, the lift in both volume and price has carried into 2026," Schwind added.

FINANCIAL CONDITION

Total assets were $2.3 billion as of March 31, 2026, an increase of $42.5 million compared to December 31, 2025, primarily due to increases of $23.1 million in interest bearing cash and $22.6 million in loans.

Available-for-sale (“AFS”) securities at fair value were $492.7 million as of March 31, 2026, a decrease of $5.0 million compared to December 31, 2025. The decrease during the quarter was largely driven by maturities and principal paydowns totaling $53.1 million, which were offset by purchases of $48.9 million. Net unrealized losses on AFS securities were $10.6 million as of March 31, 2026, compared to $9.9 million at December 31, 2025. Net unrealized losses as a percentage of the amortized cost of AFS securities were consistent compared to December 31, 2025, at 2%.

Loans were $1.6 billion as of March 31, 2026, an increase of $22.6 million compared to December 31, 2025. Adjusted loans (non-GAAP), which exclude advances to mortgage brokers, increased by $27.2 million from year-end 2025. Advances to mortgage brokers decreased by $4.6 million in first quarter 2026 due to decreased participation demand from the counterparty.

In first quarter 2026, the commercial real estate and residential mortgage portfolios increased by $20.9 million and $10.5 million, respectively. Most residential originations were adjustable-rate products, which are retained on the balance sheet rather than sold in the secondary market. The consumer loan portfolio continued to decline in 2026 amid decreasing demand, competition, and adherence to credit quality standards.

The allowance for credit losses ("ACL") was $14.0 million at March 31, 2026, an increase of $287,000 from December 31, 2025. The increase is due to loan growth and an increase in loss rates driven by loans charged off during the quarter. Nonaccrual loans were $4.4 million as of March 31, 2026 compared to $4.6 million at

December 31, 2025. Past due and accruing accounts between 30 to 89 days as a percentage of loans was 0.37% at March 31, 2026, compared to 0.44% at December 31, 2025. The Company believes its credit quality remains strong.

Total deposits were $1.9 billion at March 31, 2026, an increase of $40.2 million from December 31, 2025. The growth was driven in part by new customer relationships and included a $40.9 million increase in money market accounts and a $20.3 million increase in savings deposits. The growth was offset by a $15.1 million decrease in noninterest bearing deposits and a $3.7 million decrease in certificates of deposit.

Total equity was $234.0 million, or $31.90 per share, at March 31, 2026 compared to $231.4 million, or $31.60 per share, at December 31, 2025. Tangible book value per share (non-GAAP) was $25.32 as of March 31, 2026, compared to $25.01 as of December 31, 2025. Net unrealized losses in the AFS securities portfolio reduced tangible book value per share by $1.17 and $1.09 for the respective periods. Share repurchases totaled 8,062 during 2026 at an average price of approximately $49.86 per share.

RESULTS OF OPERATIONS

Net income in first quarter 2026 was $5.0 million, or $0.68 per diluted share, compared with $3.9 million, or $0.53 per diluted share, in first quarter 2025.

Net interest income was $16.9 million in first quarter 2026 compared to $14.5 million in first quarter 2025, representing 3.33% and 3.06% of earning assets, or NIM, respectively. The book yield from securities was 2.52% and 2.20% during the first quarters of 2026 and 2025, respectively. The yield on loans increased to 5.78% in first quarter 2026 from 5.71% in first quarter 2025. The increase in loan yields was primarily due to higher rates on new loans and variable rate commercial loans that continue to reprice. The cost of interest-bearing liabilities in first quarter 2026 decreased to 2.14% from 2.26% in first quarter 2025 primarily due to lower rates on the money market and certificate of deposit products.

The provision for credit losses in first quarter 2026 was $604,000, which reflects a $287,000 increase in the ACL on loans, net charge offs totaling $253,000, and an increase in the reserve for unfunded commitments. The provision for credit losses in first quarter 2025 was a credit of $107,000 due to the change in allowance for credit losses on loans and $52,000 in net recoveries, offset by an increase in the reserve for unfunded commitments.

Noninterest income was $4.4 million in first quarter 2026 compared to $3.5 million in first quarter 2025. Service charges and fees increased $398,000 compared to first quarter 2025, mostly due to initiatives to align our fees with the market. Wealth management fees grew $129,000 compared to first quarter 2025 due to the growth in assets under management since first quarter 2025. Earnings on bank-owned life insurance (“BOLI”) policies increased $76,000 compared to first quarter 2025 due to new investments in a separate account BOLI in 2025. Other noninterest income in first quarter 2026 included a $131,000 gain related to a death benefit from a BOLI policy.

Noninterest expenses were $14.7 million in first quarter 2026 compared to $13.3 million in first quarter 2025. Compensation and benefit expenses increased $545,000, reflecting annual merit increases, incentives, and higher medical insurance claims compared to first quarter 2025. Other professional services increased $304,000 as a result of costs related to profitability initiatives and product implementation costs.

Income tax expense was $985,000 in first quarter 2026, compared to $912,000 in first quarter 2025. The effective tax rate (ETR) was 16% and 19% for the first quarters of 2026 and 2025, respectively. The ETR in first quarter 2025 included a one-time tax expense totaling $166,000 due to the taxes owed from the lifetime earnings on BOLI policies that were surrendered during first quarter 2025. Excluding the one-time charge, the ETR was 15% for the first three months of 2025.

About Isabella Bank Corporation

Isabella Bank Corporation (Nasdaq: ISBA) is the parent holding company of Isabella Bank, a state-chartered community bank headquartered in Mt. Pleasant, Michigan. Isabella Bank was established in 1903 and has been committed to serving its customers’ and communities’ local banking needs for over 120 years. The Bank offers personal and commercial lending and deposit products, as well as investment, trust, and estate planning services. The Bank has locations throughout eight Mid-Michigan counties: Bay, Clare, Gratiot, Isabella, Mecosta, Midland, Montcalm, and Saginaw.

For more information about Isabella Bank Corporation, visit the Investor Relations link at www.isabellabank.com.

Contact

Lori Peterson, Director of Marketing

Phone: 989-779-6333 Fax: 989-775-5501

Available Information

The Company maintains an Internet web site at ir.isabellabank.com/overview. The Company makes available, free of charge, on its web site the Company’s annual reports, quarterly earnings reports, and other press releases.

The Company routinely posts important information for investors on its website (www.isabellabank.com and, more specifically, under the News tab at ir.isabellabank.com/news). The Company intends to use its web site as a means of disclosing material non-public information and for complying with its disclosure obligations under Regulation FD (Fair Disclosure) promulgated by the U.S. Securities and Exchange Commission (the “SEC”). Accordingly, investors should monitor the Company’s web site, in addition to following the Company’s press releases, SEC filings, public conference calls, presentations and webcasts.

The information contained on, or that may be accessed through, the Company’s website is not incorporated by reference into, and is not a part of, this document.

Forward-Looking Statements

Information in this press release contains certain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Rule 175 promulgated thereunder, and Section 21E of the Securities Exchange Act of 1934, as amended and Rule 3b-6 promulgated thereunder. We intend such forward looking statements to be covered by the safe harbor provisions for forward looking statements contained in the Private Securities Litigation Reform Act of 1995, and are included in this statement for purposes of these safe harbor provisions. Forward-looking statements generally relate to losses, impact of events, financial condition, plans, objectives, outlook for earnings, revenues, expenses, capital and liquidity levels and ratios, asset levels, asset quality, financial position, and other matters regarding or affecting the Company and its future business and operations. Forward-looking statements are typically identified by words or phrases such as “will likely result”, “expect”, “could”, “may”, “plan”, “believe”, “estimate”, “anticipate”, “strategy”, “trend”, “forecast”, “outlook”, “project”, “intend”, “assume”, “outcome”, “continue”, “remain”, “potential”, “opportunity”, “current”, “position”, “maintain”, “sustain”, “seek”, “achieve” and variations of such words and similar expressions, or future or conditional verbs such as will, would, should, could or may. Factors that could cause such differences include, but are not limited to: (i) the impact on us or our customers of a decline in general economic conditions, and any regulatory responses thereto; (ii) slower economic growth rates or potential recession in the United States and our market areas; (iii) uncertainty or perceived instability in the banking industry as a whole; (iv) increased competition for deposits among traditional and nontraditional financial services companies, and related changes in deposit customer behavior; (v) the impact of changes in market interest rates, whether due to a continuation of the elevated interest rate environment or further reductions in interest rates and a resulting decline in net interest income; (vi) the lingering inflationary pressures, and the risk of the resurgence of elevated levels of inflation, in the United States and our market areas; (vii) the uncertain impacts of ongoing quantitative tightening and current and future monetary policies of the Board of Governors of the Federal Reserve System; (viii) changes in unemployment rates in the United States and our market areas; (ix) adverse changes in customer spending, borrowing and savings habits; (x) declines in commercial real estate values and prices; (xi) a deterioration of the credit rating for the United States long-term sovereign debt or the impact of uncertain or changing political conditions, including federal government shutdowns and uncertainty regarding United States fiscal debt, deficit and budget matters; (xii) cyber incidents or other failures, disruptions or breaches of our operational or security systems or infrastructure, or those of our third-party vendors or other service providers, including as a result of cyber-attacks; (xiii) severe weather, natural disasters, acts of war or terrorism, geopolitical instability, domestic civil unrest or other external events, including as a result of the policies of the current U.S. presidential administration or Congress; (xiv) in the impact of tariffs, sanctions and other trade policies of the United States and its global trading counterparts and the resulting impact on the Company and its customers; (xv) competition and market expansion opportunities; (xvi) changes in non-interest expenditures or in the anticipated benefits of such expenditures; (xvii) changes in accounting principles and standards, including those related to loan loss recognition under the current expected credit loss, or CECL, methodology; (xviii) the receipt of required regulatory approvals; (xix) changes in tax laws; (xx) the risks related to the development, implementation, use and management of emerging technologies, including artificial intelligence and machine learnings; (xxi) potential costs related to the impacts of climate change; (xxii) current or future litigation, regulatory examinations or other legal and/or regulatory actions; and (xxiii) changes in applicable laws and regulations. These forward-looking statements are based on current information and/or management’s good faith belief as to future events. Although we believe the assumptions upon which these forward-looking statements are based are reasonable, any of these assumptions could prove to be inaccurate and the forward-looking statements based on these assumptions could be incorrect. Therefore, the Company can give no assurance that the results contemplated in the forward-looking statements will be realized. Additional information regarding risks and uncertainties to which the Company’s business and future financial performance are subject is contained in the Company’s most recent Annual Report on Form 10-K and Quarterly Reports on Form 10-Q on file with the SEC, including the sections entitled “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” of such documents, and other documents the Company files or furnishes with the SEC from time to time, which are available on the SEC’s website, www.sec.gov. Due to these and other possible uncertainties and risks, the Company cautions you not to unduly rely on forward-looking statements. The inclusion of this forward-looking information should not be construed as a representation by the Company or by any person that the future events, plans or expectations contemplated by the Company will be achieved. All subsequent written and oral forward-looking statements attributable to the Company or any person acting on its behalf are expressly qualified in their entirety by the cautionary statements above. Any forward-looking statement speaks only as to the date on which it is made, and we undertake no obligation to update any forward-looking statement to reflect developments occurring after the statement is made, except as required by law. All forward-looking statements, express or implied, included in the press release are qualified in their entirety by this cautionary statement.

Non-GAAP Financial Measures

Some of the financial measures included in this press release are not measures of financial performance recognized in accordance with generally accepted accounting principles in the United States (“GAAP”). The Company believes these non-GAAP financial measures provide both management and investors with a more complete understanding of the Company’s financial position and performance. These non-GAAP financial measures are supplemental and are not a substitute for any analysis based on GAAP financial measures.

We classify a financial measure as being a non-GAAP financial measure if that financial measure excludes or includes amounts, or is subject to adjustments that have the effect of excluding or including amounts, that are included or excluded, as the case may be, in the most directly comparable measure calculated and presented in accordance with GAAP as in effect from time to time in the United States in our statements of income, balance sheets or statements of cash flows. Not all companies use the same calculation of these measures; therefore, this presentation may not be comparable to other similarly titled measures as presented by other companies.

A reconciliation of non-GAAP financial measures to GAAP financial measures is provided at the end of this press release.

Table Index Consolidated Financial Schedules (Unaudited)

A Selected Financial Data

B Consolidated Balance Sheets

C Consolidated Statements of Income

Average Balances, Interest Rate, and Net Interest Income

Reconciliation of Non-GAAP Financial Measures

SELECTED FINANCIAL DATA (UNAUDITED)

(Dollars in thousands except per share amounts and ratios)

The following table outlines selected financial data as of, and for the:

Three Months Ended

March 31

2026 December 31

2025 September 30

2025 June 30

2025 March 31

2025

PER SHARE

Basic earnings $ 0.68 $ 0.64 $ 0.71 $ 0.68 $ 0.53

Diluted earnings 0.68 0.64 0.71 0.68 0.53

Dividends 0.28 0.28 0.28 0.28 0.28

Book value (1)

31.90 31.60 30.94 29.95 29.10

Tangible book value (1) (2)

25.32 25.01 24.37 23.39 22.58

Market price (1)

45.67 50.00 35.25 30.15 23.59

Common shares outstanding (1) (3)

7,333,319 7,322,207 7,350,567 7,361,684 7,408,010

Average number of diluted common shares outstanding (3)

7,329,058 7,345,610 7,371,652 7,398,109 7,432,162

PERFORMANCE RATIOS

Return on average total assets 0.91% 0.85% 0.94% 0.96% 0.77%

Return on average shareholders’ equity 8.58% 8.04% 9.28% 9.19% 7.48%

Return on average tangible shareholders’ equity (2)

10.79% 10.16% 11.83% 11.78% 9.65%

Net interest margin yield (fully taxable equivalent) (1)

3.33% 3.28% 3.15% 3.14% 3.06%

Efficiency ratio (2)

68.50% 65.02% 67.62% 72.14% 72.39%

Loan to deposit ratio (1)

83.82% 84.43% 74.36% 75.57% 76.07%

Shareholders’ equity to total assets (1)

10.39% 10.47% 10.06% 10.23% 10.25%

Tangible shareholders’ equity to tangible assets (1)

8.43% 8.47% 8.10% 8.17% 8.14%

ASSETS UNDER MANAGEMENT

Wealth assets under

management (1)

701,510 707,118 679,724 678,959 656,617

ASSET QUALITY

Nonaccrual loans (1)

4,418 4,578 3,443 1,164 173

Foreclosed assets (1)

573 938 1,018 667 649

Net loan charge-offs (recoveries) 253 34 74 (1,432) (52)

Net loan charge-offs (recoveries) to average loans outstanding 0.02% 0.00% 0.01% (0.10%) 0.00%

Nonperforming loans to total loans (1)

0.28% 0.30% 0.24% 0.09% 0.01%

Nonperforming assets to total assets (1)

0.22% 0.25% 0.20% 0.09% 0.04%

Allowance for credit losses to loans (1)

0.90% 0.89% 0.92% 0.93% 0.93%

CAPITAL RATIOS (1)

Tier 1 leverage 8.89% 8.84% 8.71% 9.04% 8.96%

Common equity tier 1 capital 11.71% 11.73% 12.37% 12.46% 12.58%

Tier 1 risk-based capital 11.71% 11.73% 12.37% 12.46% 12.58%

Total risk-based capital 14.01% 14.41% 15.20% 15.34% 15.50%

(1) At end of period

(2) Non-GAAP financial measure; refer to the Reconciliation of Non-GAAP Financial Measures (Unaudited) in table E

(3) Whole shares

CONSOLIDATED BALANCE SHEETS (UNAUDITED)

(Dollars in thousands)

March 31

2026 December 31

2025 September 30

2025 June 30

2025 March 31

2025

ASSETS

Cash and demand deposits due from banks $ 23,896 $ 22,935 $ 32,124 $ 34,246 $ 28,786

Federal funds sold and interest bearing balances due from banks 26,209 3,106 129,177 74,308 40,393

Total cash and cash equivalents 50,105 26,041 161,301 108,554 69,179

Marketable securities available-for-sale (amortized cost of $503,366 and $507,689, respectively)

492,744 497,791 511,970 500,560 513,040

Mortgage loans held-for-sale 360 423 737 55 127

Loans held for investment 1,558,941 1,536,364 1,431,905 1,397,513 1,367,724

Less allowance for credit losses 14,014 13,727 13,149 12,977 12,735

Net loans 1,544,927 1,522,637 1,418,756 1,384,536 1,354,989

Federal Home Loan Bank stock, at cost 5,600 5,600 5,600 5,600 5,600

Premises and equipment 29,064 29,000 28,659 28,171 28,108

Cash surrender value of bank-owned life insurance policies 46,173 46,133 45,651 45,774 45,833

Goodwill and other intangible assets 48,282 48,282 48,282 48,282 48,282

Other assets 34,701 33,541 38,698 34,636 37,429

Total assets $ 2,251,956 $ 2,209,448 $ 2,259,654 $ 2,156,168 $ 2,102,587

LIABILITIES AND SHAREHOLDERS’ EQUITY

Liabilities

Noninterest bearing deposits $ 411,216 $ 426,342 $ 421,027 $ 493,477 $ 404,194

Interest bearing demand deposits 263,954 266,187 248,666 223,376 243,939

Money market deposits 477,544 436,631 558,212 446,845 473,138

Savings 300,732 280,429 292,899 289,746 286,399

Certificates of deposit 406,399 410,065 404,798 395,932 390,239

Total deposits 1,859,845 1,819,654 1,925,602 1,849,376 1,797,909

Short-term borrowings 113,530 68,000 62,022 43,208 47,310

Federal Home Loan Bank advances — 45,000 — — —

Subordinated debt, net of unamortized issuance costs 29,537 29,514 29,492 29,469 29,447

Total borrowed funds 143,067 142,514 91,514 72,677 76,757

Other liabilities 15,083 15,884 15,118 13,615 12,365

Total liabilities 2,017,995 1,978,052 2,032,234 1,935,668 1,887,031

Shareholders’ equity

Common stock 123,251 123,204 124,284 124,607 125,547

Shares to be issued for deferred compensation obligations 2,522 2,366 2,373 2,331 2,508

Retained earnings 116,790 113,849 111,172 107,949 104,940

Accumulated other comprehensive loss (8,602) (8,023) (10,409) (14,387) (17,439)

Total shareholders’ equity 233,961 231,396 227,420 220,500 215,556

Total liabilities and shareholders’ equity $ 2,251,956 $ 2,209,448 $ 2,259,654 $ 2,156,168 $ 2,102,587

CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)

(Dollars in thousands except per share amounts)

Three Months Ended

March 31

2026 December 31

2025 September 30

2025 June 30

2025 March 31

2025

Interest income

Loans, including fees $ 21,464 $ 21,669 $ 20,583 $ 19,832 $ 19,348

Available-for-sale securities

Taxable 2,489 2,539 2,478 2,513 2,103

Nontaxable 499 509 516 519 540

Federal Home Loan Bank stock, at cost 75 63 70 125 160

Federal funds sold and other 602 498 1,235 253 482

Total interest income 25,129 25,278 24,882 23,242 22,633

Interest expense

Deposits 7,112 7,380 8,012 7,391 7,463

Short-term borrowings 736 587 441 324 341

Federal Home Loan Bank advances 133 317 — 132 38

Subordinated debt 266 266 267 266 266

Total interest expense 8,247 8,550 8,720 8,113 8,108

Net interest income 16,882 16,728 16,162 15,129 14,525

Provision (reversal) for credit losses 604 434 209 (1,099) (107)

Net interest income after provision for credit losses 16,278 16,294 15,953 16,228 14,632

Noninterest income

Service charges and fees 2,372 2,461 2,352 2,071 1,974

Wealth management fees 1,108 1,110 1,074 1,084 979

Income from bank-owned life insurance policies 448 485 468 300 372

Net gain on sale of mortgage loans 33 65 38 47 30

Other 400 323 376 184 173

Total noninterest income 4,361 4,444 4,308 3,686 3,528

Noninterest expenses

Compensation and benefits 7,928 7,532 7,630 7,496 7,383

Occupancy and equipment 2,840 2,663 2,628 2,650 2,600

Other professional services 1,015 815 851 863 711

ATM and debit card fees 558 575 595 555 486

Marketing 506 547 514 469 459

FDIC insurance premiums 306 339 271 267 303

Other 1,509 1,450 1,496 1,445 1,357

Total noninterest expenses 14,662 13,921 13,985 13,745 13,299

Income before income tax expense 5,977 6,817 6,276 6,169 4,861

Income tax expense 985 2,127 1,036 1,138 912

Net income $ 4,992 $ 4,690 $ 5,240 $ 5,031 $ 3,949

Earnings per common share

Basic $ 0.68 $ 0.64 $ 0.71 $ 0.68 $ 0.53

Diluted 0.68 0.64 0.71 0.68 0.53

Cash dividends per common share 0.28 0.28 0.28 0.28 0.28

AVERAGE BALANCES, INTEREST RATE, AND NET INTEREST INCOME (UNAUDITED)

(Dollars in thousands)

The following schedules present the daily average amount outstanding for each major category of interest earning assets, non-earning assets, interest bearing liabilities, and noninterest bearing liabilities. These schedules also present an analysis of interest income and interest expense for the periods indicated. All interest income is reported on a fully tax equivalent ("FTE") basis using a federal income tax rate of 21%. Loans in nonaccrual status, for the purpose of the following computations, are included in the average loan balances. Federal Reserve Bank ("FRB") restricted equity holdings are included in other interest earning assets.

Three Months Ended

March 31, 2026 December 31, 2025 March 31, 2025

Average

Balance Tax

Equivalent

Interest Average

Yield /

Rate Average

Balance Tax

Equivalent

Interest Average

Yield /

Rate Average

Balance Tax

Equivalent

Interest Average

Yield /

Rate

INTEREST EARNING ASSETS

Loans (1)

$ 1,501,654 $ 21,464 5.78 % $ 1,493,654 $ 21,669 5.74 % $ 1,370,765 $ 19,348 5.71 %

AFS securities (2) (3)

498,254 3,126 2.52 % 515,050 3,186 2.47 % 514,479 2,827 2.20 %

Federal Home Loan Bank stock, at cost 5,600 75 5.36 % 5,600 63 4.54 % 11,011 160 5.82 %

Federal funds sold 7 — 3.54 % 9 — 3.86 % 4 — 4.32 %

Other (4)

64,190 602 3.75 % 28,344 498 6.88 % 47,374 482 4.06 %

Total interest earning assets (3)

2,069,705 25,267 4.94 % 2,042,657 25,416 4.94 % 1,943,633 22,817 4.75 %

NONEARNING ASSETS

Allowance for credit losses (13,680) (13,213) (12,884)

Cash and demand deposits due from banks 23,113 23,239 23,899

Premises and equipment 29,110 29,009 27,962

Other assets 116,639 117,201 102,927

Total assets $ 2,224,887 $ 2,198,893 $ 2,085,537

INTEREST BEARING LIABILITIES

Interest bearing demand deposits $ 266,101 294 0.45 % $ 249,809 211 0.34 % $ 240,860 242 0.41 %

Money market deposits 464,438 2,719 2.37 % 449,129 2,900 2.56 % 460,663 2,929 2.58 %

Savings 291,413 488 0.68 % 282,306 498 0.70 % 286,364 538 0.76 %

Certificates of deposit 407,483 3,611 3.59 % 408,861 3,771 3.66 % 387,820 3,754 3.93 %

Short-term borrowings 86,885 736 3.44 % 67,521 587 3.45 % 43,563 341 3.18 %

Federal Home Loan Bank advances 13,444 133 3.96 % 30,163 317 4.12 % 3,333 38 4.53 %

Subordinated debt, net of unamortized issuance costs

29,522 266 3.61 % 29,500 266 3.61 % 29,433 266 3.62 %

Total interest bearing liabilities 1,559,286 8,247 2.14 % 1,517,289 8,550 2.24 % 1,452,036 8,108 2.26 %

NONINTEREST BEARING LIABILITIES AND SHAREHOLDERS’ EQUITY

Demand deposits 411,011 432,038 403,024

Other liabilities 18,653 18,182 16,265

Shareholders’ equity 235,937 231,384 214,212

Total liabilities and shareholders’ equity $ 2,224,887 $ 2,198,893 $ 2,085,537

Net interest income (FTE) (5)

$ 17,020 $ 16,866 $ 14,709

Net yield on interest earning assets (FTE) (5)

3.33 % 3.28 % 3.06 %

(1) Includes loans held-for-sale and nonaccrual loans

(2) Average balances for available-for-sale securities are based on amortized cost

(3) Includes FTE adjustments of $138, $138, and $184, respectively

(4) Includes average interest bearing deposits with other banks, net of Federal Reserve daily cash letter

(5) Non-GAAP financial measure; refer to the Reconciliation of Non-GAAP Financial Measures (Unaudited) in table E

RECONCILIATION OF NON-GAAP FINANCIAL MEASURES (UNAUDITED)

(Dollars in thousands except per share amounts and ratios)

Three Months Ended

March 31

2026 December 31

2025 September 30

2025 June 30

2025 March 31

2025

Loans $ 1,558,941 $ 1,536,364 $ 1,431,905 $ 1,397,513 $ 1,367,724

Advances to mortgage brokers 72,083 76,676 5,056 3,005 3,015

Adjusted loans $ 1,486,858 $ 1,459,688 $ 1,426,849 $ 1,394,508 $ 1,364,709

Total shareholders’ equity $ 233,961 $ 231,396 $ 227,420 $ 220,500 $ 215,556

Goodwill and other intangible assets 48,282 48,282 48,282 48,282 48,282

Tangible equity (A) 185,679 183,114 179,138 172,218 167,274

Common shares outstanding (1)

(B) 7,333,319 7,322,207 7,350,567 7,361,684 7,408,010

Tangible book value per share (A/B) $ 25.32 $ 25.01 $ 24.37 $ 23.39 $ 22.58

Noninterest expenses $ 14,662 $ 13,921 $ 13,985 $ 13,745 $ 13,299

Amortization of acquisition intangibles — — — — 1

Adjusted noninterest expense (C) $ 14,662 $ 13,921 $ 13,985 $ 13,745 $ 13,298

Net interest income $ 16,882 $ 16,728 $ 16,162 $ 15,129 $ 14,525

Tax equivalent adjustment for net interest margin 138 138 144 178 184

Net interest income (FTE) 17,020 16,866 16,306 15,307 14,709

Noninterest income 4,361 4,444 4,308 3,686 3,528

Tax equivalent adjustment for BOLI 94 102 98 63 78

Adjusted revenue (FTE) 21,475 21,412 20,712 19,056 18,315

Net gains (losses) on foreclosed assets 70 3 31 3 (55)

Adjusted revenue (D) $ 21,405 $ 21,409 $ 20,681 $ 19,053 $ 18,370

Efficiency ratio (C/D) 68.50% 65.02% 67.62% 72.14% 72.39%

(1) Whole shares

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Apr. 23, 2026

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ISABELLA BANK CORP

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