S&T BANCORP INC (STBA)

Item 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

Management’s Discussion and Analysis of Financial Condition and Results of Operations, or MD&A, represents an overview of our consolidated results of operations and financial condition and highlights material changes in our financial condition and results of operations for the three months ended March 31, 2026 and 2025. Our MD&A should be read in conjunction with our Condensed Consolidated Financial Statements and Notes. The results of operations reported in the accompanying Condensed Consolidated Financial Statements are not necessarily indicative of results to be expected in future periods.

Important Note Regarding Forward-Looking Statements

This Quarterly Report on Form 10-Q contains or incorporates statements that we believe are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements generally relate to our financial condition, results of operations, 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 S&T and its future business and operations. Forward-looking statements are typically identified by words or phrases such as “will likely result,” “expect,” “anticipate,” “estimate,” “forecast,” “project,” “intend,” “believe,” “assume,” “strategy,” “trend,” “plan,” “outlook,” “outcome,” “continue,” “remain,” “potential,” “opportunity,” “comfortable,” “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.” 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. The matters discussed in these forward-looking statements are subject to various risks, uncertainties and other factors that could cause actual results and trends to differ materially from those made, projected or implied in or by the forward-looking statements depending on a variety of uncertainties or other factors including, but not limited to: credit losses and the credit risk of our commercial and consumer loan products; changes in the level of charge-offs and changes in estimates of the adequacy of the allowance for credit losses, or ACL; cybersecurity concerns; rapid technological developments and changes, including the use of artificial intelligence and digital assets; operational risks or risk management failures by us or critical third parties, including fraud risk; our ability to manage our brand risks; sensitivity to the interest rate environment, a rapid increase in interest rates or a change in the shape of the yield curve; a change in spreads on interest-earning assets and interest-bearing liabilities; regulatory supervision and oversight, including changes in regulatory capital requirements and our ability to address those requirements; unanticipated changes in our liquidity position; unanticipated changes in regulatory and governmental policies impacting interest rates and financial markets; changes in accounting policies, practices or guidance; legislation affecting the financial services industry as a whole, and S&T, in particular; developments affecting the industry and the soundness of financial institutions and further disruption to the economy and U.S. banking system; the outcome of pending and future litigation and governmental proceedings; increasing price and product/service competition; the ability to continue to introduce competitive new products and services on a timely, cost-effective basis; managing our internal growth and acquisitions; the possibility that the anticipated benefits from acquisitions cannot be fully realized in a timely manner or at all, or that integrating the acquired operations will be more difficult, disruptive or costly than anticipated; containing costs and expenses; reliance on significant customer relationships; an interruption or cessation of an important service by a third-party provider; our ability to attract and retain talented executives and other employees; general economic or business conditions, including the strength of regional economic conditions in our market area; ESG practices and disclosures, including climate change, hiring practices, the diversity of the work force and racial and social justice issues; deterioration of the housing market and reduced demand for mortgages; deterioration in the overall macroeconomic conditions or the state of the banking industry that could warrant further analysis of the carrying value of goodwill and could result in an adjustment to its carrying value resulting in a non-cash charge to net income; the stability of our core deposit base and access to contingency funding; re-emergence of turbulence in significant portions of the global financial and real estate markets that could impact our performance, both directly, by affecting our revenues and the value of our assets and liabilities, and indirectly, by affecting the economy generally and access to capital in the amounts, at the times and on the terms required to support our future businesses and geopolitical tensions and conflicts between nations.

Many of these factors, as well as other factors, are described elsewhere in this report, and under Part I, Item 1A - “Risk Factors” of our 2025 Form 10-K, and any of our subsequent filings with the SEC. Forward-looking statements are based on beliefs and assumptions using information available at the time the statements are made. We caution you not to unduly rely on forward-looking statements because the assumptions, beliefs, expectations and projections about future events may, and often do, differ materially from actual results. 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.

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Critical Accounting Policies and Estimates

We view critical accounting policies to be those which are highly dependent on subjective or complex estimates, assumptions and judgments and where changes in those estimates and assumptions could have a significant impact on the Condensed Consolidated Financial Statements. Further, we view critical accounting estimates as those estimates made in accordance with GAAP that involve a significant level of estimation uncertainty and have had or are reasonably likely to have a material impact on our financial condition or results of operations. Our critical accounting policies and estimates as of March 31, 2026 remained unchanged from the disclosures presented in our 2025 Form 10-K under Part II, Item 7 - “Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

Explanation of Use of Non-GAAP Financial Measures

In addition to traditional financial measures presented in accordance with GAAP, our management uses, and this report contains or references, certain non-GAAP financial measures, such as interest income on interest-earning assets, net interest income and net interest margin presented on a fully taxable equivalent, or FTE, basis (non-GAAP), the efficiency ratio (non-GAAP) and return on tangible shareholders' equity (non-GAAP).

We believe these non-GAAP financial measures provide information useful to investors in understanding our underlying business, operational performance and performance trends as they facilitate comparisons with the performance of other companies in the financial services industry. Although we believe that these non-GAAP financial measures enhance investors’ understanding of our business and performance, these non-GAAP financial measures should not be considered alternatives to GAAP or considered to be more important than financial results determined in accordance with GAAP, nor are they necessarily comparable with non-GAAP measures which may be presented by other companies.

The following table reconciles interest and dividend income and net interest income per the Condensed Consolidated Statements of Comprehensive Income to interest income, net interest income and net interest margin on an FTE basis (non-GAAP) for the periods presented. The FTE basis (non-GAAP) adjusts for the tax benefit of income on certain tax-exempt loans and securities and the dividend-received deduction for equity securities using the federal statutory tax rate of 21 percent for each period. We believe this to be the preferred industry measurement of net interest income that provides a relevant comparison combining both taxable and non-taxable sources of interest income.

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Return on average tangible shareholders' equity (non-GAAP) is a key profitability metric used by management to measure financial performance. The following table provides a reconciliation of return on average tangible shareholders' equity (non-GAAP) by reconciling net income (GAAP) per the Condensed Consolidated Statements of Comprehensive Income to net income before amortization of intangibles and average shareholder's equity to average tangible shareholders' equity for the periods presented:

Executive Overview

We are a bank holding company that is headquartered in Indiana, Pennsylvania with assets of $9.9 billion at March 31, 2026. We operate in Pennsylvania and Ohio providing a full range of financial services with retail, business banking and commercial banking products and trust and brokerage services. Our common stock trades on the NASDAQ Global Select Market under the symbol “STBA.”

We earn revenue primarily from interest on loans and securities and fees charged for financial services provided to our customers. We incur expens

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Item 7.  MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

This section reviews our financial condition for each of the past two fiscal years and results of operations for each of the past three fiscal years. Management's discussion and analysis focuses on significant factors impacting the financial condition and results of operations for the year ended December 31, 2025 as compared to the year ended December 31, 2024. This discussion and analysis should be read in conjunction with our Consolidated Financial Statements and related notes within this Annual Report on Form 10-K. A similar discussion and analysis that compares the year ended December 31, 2024 to the year ended December 31, 2023 may be found in Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations” on our Form 10-K for the year ended December 31, 2024 accepted by the Securities and Exchange Commission, or SEC, on February 28, 2025. Certain reclassifications have been made to prior periods to conform to the current period presentation.

Important Note Regarding Forward-Looking Statements

This Annual Report on Form 10-K contains or incorporates statements that we believe are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements generally relate to our financial condition, results of operations, 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 S&T and its future business and operations. Forward-looking statements are typically identified by words or phrases such as “will likely result,” “expect,” “anticipate,” “estimate,” “forecast,” “project,” “intend,” “believe,” “assume,” “strategy,” “trend,” “plan,” “outlook,” “outcome,” “continue,” “remain,” “potential,” “opportunity,” “comfortable,” “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.” 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. The matters discussed in these forward-looking statements are subject to various risks, uncertainties and other factors that could cause actual results and trends to differ materially from those made, projected or implied in or by the forward-looking statements depending on a variety of uncertainties or other factors including, but not limited to: credit losses and the credit risk of our commercial and consumer loan products; changes in the level of charge-offs and changes in estimates of the adequacy of the allowance for credit losses, or ACL; cybersecurity concerns; rapid technological developments and changes, including the use of artificial intelligence and digital assets; operational risks or risk management failures by us or critical third parties, including fraud risk; our ability to manage our brand risks; sensitivity to the interest rate environment, a rapid increase in interest rates or a change in the shape of the yield curve; a change in spreads on interest-earning assets and interest-bearing liabilities; regulatory supervision and oversight, including changes in regulatory capital requirements and our ability to address those requirements; unanticipated changes in our liquidity position; unanticipated changes in regulatory and governmental policies impacting interest rates and financial markets; changes in accounting policies, practices or guidance; legislation affecting the financial services industry as a whole, and S&T, in particular; developments affecting the industry and the soundness of financial institutions and further disruption to the economy and U.S. banking system; the outcome of pending and future litigation and governmental proceedings; increasing price and product/service competition; the ability to continue to introduce competitive new products and services on a timely, cost-effective basis; managing our internal growth and acquisitions; the possibility that the anticipated benefits from acquisitions cannot be fully realized in a timely manner or at all, or that integrating the acquired operations will be more difficult, disruptive or costly than anticipated; containing costs and expenses; reliance on significant customer relationships; an interruption or cessation of an important service by a third-party provider; our ability to attract and retain talented executives and other employees; general economic or business conditions, including the strength of regional economic conditions in our market area; ESG practices and disclosures, including climate change, hiring practices, the diversity of the work force and racial and social justice issues; deterioration of the housing market and reduced demand for mortgages; deterioration in the overall macroeconomic conditions or the state of the banking industry that could warrant further analysis of the carrying value of goodwill and could result in an adjustment to its carrying value resulting in a non-cash charge to net income; the stability of our core deposit base and access to contingency funding; re-emergence of turbulence in significant portions of the global financial and real estate markets that could impact our performance, both directly, by affecting our revenues and the value of our assets and liabilities, and indirectly, by affecting the economy generally and access to capital in the amounts, at the times and on the terms required to support our future businesses and geopolitical tensions and conflicts between nations.

Many of these factors, as well as other factors, are described elsewhere in this report, including Part I, Item 1A, Risk Factors and any of our subsequent filings with the SEC. Forward-looking statements are based on beliefs and assumptions using information available at the time the statements are made. We caution you not to unduly rely on forward-looking statements because the assumptions, beliefs, expectations and projections about future events may, and often do, differ materially from actual results. 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.

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Critical Accounting Policies and Estimates

Our consolidated financial statements are prepared in accordance with U.S. generally accepted accounting principles, or GAAP. Application of these principles requires management to make estimates, assumptions and judgments that affect the amounts reported in the consolidated financial statements and accompanying notes. These estimates, assumptions and judgments are based on information available as of the date of the consolidated financial statements; accordingly, as this information changes, the consolidated financial statements could reflect different estimates, assumptions and judgments. Certain policies are based, to a greater extent, on estimates, assumptions and judgments of management and, as such, have a greater possibility of producing results that could be materially different than originally reported.

Our most significant accounting policies are presented in Note 1. Summary of Significant Accounting Policies in the Notes to Consolidated Financial Statements included in Part II, Item 8 of this Report. These policies, along with the disclosures presented in the Notes to Consolidated Financial Statements, provide information on how significant assets and liabilities are valued in the consolidated financial statements and how those values are determined.

We view critical accounting policies to be those which are highly dependent on subjective or complex estimates, assumptions and judgments and where changes in those estimates and assumptions could have a significant impact on the consolidated financial statements. Further, we view critical accounting estimates as those estimates made in accordance with GAAP that involve a significant level of estimation uncertainty and have had or are reasonably likely to have a material impact on our financial condition or results of operations. We currently view the determination of the ACL and goodwill to be critical accounting policies. We did not significantly change the manner in which we applied our critical accounting policies or developed related assumptions or estimates during 2025. We have reviewed these critical accounting estimates and related disclosures with the Audit Committee.

Allowance for Credit Losses

Our expected credit loss methodology requires consideration of a broader range of information to estimate expected credit losses over the lifetime of an asset. The ACL is a valuation reserve established and maintained by charges against operating income. It is an estimate of expected credit losses, measured over the contractual life of a loan, that considers historical loss experience, current conditions and forecasts of future economic conditions.

Management’s evaluation process used to determine the appropriateness of the ACL is complex and requires the use of estimates, assumptions and judgments which are inherently subject to high uncertainty. The evaluation process combines several factors: historical loan loss experience, managements ongoing review of lending policies and practices, experience and depth of staff, quality of the loan grading system, the fair value of underlying collateral, concentration of loans to specific borrowers or industries, existing economic conditions and forecasts, segment specific risks and other quantitative and qualitative factors which could affect future credit losses. Our reasonable and supportable forecast is based primarily on the national unemployment forecast produced by the Federal Reserve and is for a period of two years. For periods beyond our two-year forecast, we revert to historical loss rates utilizing a straight-line method over a one-year reversion period. Because current economic conditions and forecasts can change and future events are inherently difficult to predict, the anticipated amount of estimated credit losses on loans and the appropriateness of the ACL could change significantly. It is challenging to estimate how potential changes in any one economic factor or input might affect the overall allowance because a wide variety of factors and inputs may be directionally inconsistent, such that improvement in one factor may offset deterioration in others.

In conjunction with our capital stress testing process, we consider different economic scenarios that impact the ACL. Among other balance sheet and income statement changes, our severely adverse scenario would have resulted in an increase to the ACL of approximately 107 percent. This severely adverse scenario shows how sensitive the ACL can be to key qualitative and quantitative assumptions underlying the overall ACL calculation. To the extent actual losses are higher than management estimates, additional provision for credit losses could be required and could adversely affect our earnings or financial position in future periods.

Goodwill

As a result of acquisitions, we have recorded goodwill in our Consolidated Balance Sheets. Goodwill represents the excess of the purchase price over the fair value of net assets acquired.

The acquisition method of accounting requires that assets acquired and liabilities assumed in business combinations are recorded at their fair values. This often involves estimates based on third-party valuations or internal valuations based on discounted cash flow analyses or other valuation techniques which are inherently subjective. Business combinations also typically result in goodwill which is subject to ongoing periodic impairment tests based on the fair values of the reporting units to which the acquired goodwill relates.

The carrying value of goodwill is tested annually for impairment each October 1st or more frequently if events and circumstances indicate that it may be impaired. We test for impairment by comparing the fair value of the reporting unit with its

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carrying amount. An impairment charge would be recognized if the carrying amount exceeds the reporting unit's fair value. A qualitative assessment is performed to determine whether it is more likely than not that the reporting unit's fair value is less than it's carrying value. We perform a quantitative impairment test only if we conclude that it is more likely than not that a reporting unit's fair value is less than the carrying amount. Determining the fair value of a reporting unit is judgmental and involves the use of significant estimates and assumptions. The fair value of the reporting unit is determined by using both a discounted cash flow model and market based models. The discounted cash flow model has many assumptions including future earnings projections, a long-term growth rate and discount rate. The market based method calculates the fair value based on observed price multiples for similar companies. The fair values of each method are then weighted based on the relevance and reliability in the current economic environment.

Based upon our qualitative assessment performed for our annual impairment analysis as of October 1, 2025, we concluded that goodwill is not impaired.

Recent Accounting Pronouncements and Developments

Note 1. Summary of Significant Accounting Policies in the Notes to Consolidated Financial Statements, which is included in Part II, Item 8 Financial Statements and Supplementary Data of this Report, discusses new accounting pronouncements that we have adopted and the expected impact of accounting pronouncements recently issued or proposed, but not yet required to be adopted.

Explanation of Use of Non-GAAP Financial Measures

In addition to traditional financial measures presented in accordance with GAAP, our management uses, and this report contains or references, certain non-GAAP financial measures, such as interest income on interest-earning assets, net interest income and net interest margin presented on a fully taxable equivalent, or FTE, basis (non-GAAP), the efficiency ratio (non-GAAP) and return on tangible shareholders' equity (non-GAAP).

We believe these non-GAAP financial measures provide information useful to investors in understanding our underlying business, operational performance and performance trends as they facilitate comparisons with the performance of other companies in the financial services industry. Although we believe that these non-GAAP financial measures enhance investors’ understanding of our business and performance, these non-GAAP financial measures should not be considered alternatives to GAAP or considered to be more important than financial results determined in accordance with GAAP, nor are they necessarily comparable with non-GAAP measures which may be presented by other companies.

The following table reconciles interest and dividend income and net interest income per the Consolidated Statements of Net Income to interest income, net interest income and net interest margin on an FTE basis (non-GAAP) for the periods presented. The FTE basis (non-GAAP) adjusts for the tax benefit of income on certain tax-exempt loans and securities and the dividend-received deduction for equity securities using the federal statutory tax rate of 21 percent for each period. We believe this to be the preferred industry measurement of net interest income that provides a relevant comparison combining both taxable and non-taxable sources of interest income.

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The efficiency ratio is noninterest expense divided by net interest income on an FTE basis (non-GAAP) which ensures comparability of net interest income arising from both taxable and tax-exempt sources and is consistent with industry practice, plus noninterest income adjusted to exclude losses on sales of securities and gains on Visa exchange. Below is a reconciliation of the non-GAAP efficiency ratio.

Return on average tangible shareholders' equity (non-GAAP) is a key profitability metric used by management to measure financial performance. The following table provides a reconciliation of return on average tangible shareholders' equity (non-GAAP) by reconciling net income (GAAP) per the Consolidated Statements of Net Income to net income before amortization of intangibles and average shareholder's equity to average tangible shareholders' equity for the periods presented:

Executive Overview

We are a bank holding company that is headquartered in Indiana, Pennsylvania with assets of $9.9 billion at December 31, 2025. We operate in Pennsylvania and Ohio providing a full range of financial services with retail and commercial banking products, cash management services, trust and brokerage services. Our common stock trades on the NASDAQ Global Select Market under the symbol “STBA.”

We earn revenue primarily from interest on loans and securities and fees charged for financial services provided to our customers. We incur expenses for the cost of deposits and other funding sources, provision for credit losses and other operating costs such as salaries and employee benefits, data processing, occupancy and tax expense.

Our purpose is building our future together through people-forward banking. We believe that all banking should be personal. We cultivate relationships rooted in trust, strengthened by going above and beyond and renewed with every interaction. Our strategic priorities for 2026 and beyond will be focused on growing our deposit franchise, improving core profitability, maintaining asset quality and ensuring a high level of talent and engagement.

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Earnings Summary

The following table presents a summary of key profitability metrics for the periods presented:

We earned net income of $134.2 million for 2025 compared to net income of $131.3 million in 2024. Diluted earnings per share, or EPS, was $3.49 in 2025 compared to $3.41 in 2024. The increase in both net income and EPS in 2025 can be attributed to an increase in net interest income offset by an increase in the provision for credit losses and noninterest expenses.

Net interest income increased $15.3 million, or 4.57 percent, to $350.1 million in 2025 compared to $334.8 million in 2024. Net interest income on an FTE basis (non-GAAP) increased $15.0 million, or 4.44 percent, compared to 2024. The net interest margin, or NIM, on an FTE basis (non-GAAP) increased 8 basis points to 3.90 percent in 2025 compared to 3.82 percent in 2024. The higher NIM (FTE) (non-GAAP), despite the declining interest rate environment, reflects the strategic repositioning of the balance sheet to be more interest rate neutral. NIM is reconciled to net interest margin adjusted to an FTE basis (non-GAAP) above in the "Explanation of Use of Non-GAAP Financial Measures" section of this Management’s Discussion and Analysis, or MD&A.

The provision for credit losses increased $7.3 million to $7.4 million for 2025 compared to $0.1 million for 2024. The increase primarily related to higher net loan charge-offs offset by a lower required level of ACL. Net loan charge-offs were $14.5 million, or 0.18 percent of average loans, in 2025 compared to $8.3 million, or 0.11 percent of average loans, in 2024. Higher net charge-offs were primarily due to the resolution of nonperforming assets during the fourth quarter of 2025.

Noninterest income increased $2.9 million, or 6.0 percent, to $52.0 million in 2025 compared to $49.1 million in 2024. The increase primarily related to lower security losses of $2.3 million in 2025 compared to $7.9 million in 2024 offset by a $3.5 million gain from the exchange offer for Visa Class B-1 common stock in 2024.

Noninterest expense increased $7.9 million, or 3.6 percent, to $226.8 million in 2025 compared to $218.9 million in 2024. Expenses remained relatively stable with the most significant increase related to salaries and employee benefits which increased $5.7 million primarily due to higher salary and incentive costs. The efficiency ratio (non-GAAP) for 2025 was 55.74 percent compared to 55.99 percent for 2024. A reconciliation of the efficiency ratio (non-GAAP) is provided above in the "Explanation of Use of Non-GAAP Financial Measures" section of this MD&A.

The provision for income taxes remained relatively unchanged at $33.7 million in 2025 compared to $33.6 million in 2024. The effective tax rate decreased to 20.1 percent in 2025 compared to 20.4 percent in 2024. The decrease in the effective tax rate was primarily due to an increase in low income housing tax credits, or LIHTC, net of amortization.

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Net Interest Income

Our principal source of revenue is net interest income. Net interest income represents the difference between the interest and fees earned on interest-earning assets and the interest paid on interest-bearing liabilities. Net interest income is affected by changes in the average balance of interest-earning assets and interest-bearing liabilities and changes in interest rates and spreads. The level and mix of interest-earning assets and interest-bearing liabilities is managed by our Asset and Liability Committee, or ALCO, in order to mitigate interest rate and liquidity risks of the balance sheet. A variety of ALCO strategies were implemented, within prescribed ALCO risk parameters, to produce what we believe is an acceptable level of net interest income.

As part of our interest rate risk management strategy, we use interest rate swaps to add stability to net interest income by managing our exposure to interest rate movements. During 2022, we entered into interest rate swaps with a total notional amount of $500.0 million with maturities ranging from three to five years. There were no new interest rates swaps entered into in 2023, 2024 or 2025. Our strategy is to reduce our exposure to variability in expected future cash flows related to interest payments on commercial loans that are currently indexed to the 1-month SOFR rate. Interest rates increased substantially in 2022 and 2023 followed by decreases in 2024 and 2025 resulting in an unrealized loss on the cash flow hedges of $1.6 million at December 31, 2025 which is reported in Accumulated Other Comprehensive Income (Loss), or AOCI, net of applicable taxes. This is an improvement of $5.9 million compared to the $7.5 million unrealized loss at December 31, 2024.

Average Balance Sheet and Net Interest Income Analysis (FTE) (non-GAAP)

The following tables provide information regarding the average balances, interest and rates earned on interest-earning assets and interest and rates paid on interest-bearing liabilities for the periods presented:

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(1) Tax-exempt interest income is on an FTE basis (non-GAAP) using the statutory federal corporate income tax rate of 21 percent.

(2) Taxable investment income is adjusted for the dividend-received deduction for equity securities.

(3) Nonaccruing loans are included in the daily average loan amounts outstanding.

Net interest income on an FTE basis (non-GAAP) increased $15.0 million, or 4.44 percent, to $352.5 million in 2025 compared to $337.5 million in 2024. NIM on an FTE basis (non-GAAP) increased 8 basis points to 3.90 percent compared to 3.82 percent in 2024. The increases in net interest income on a FTE basis (non-GAAP) and NIM on an FTE basis (non-GAAP) were primarily due to the impact of lower interest rates on total interest-bearing liabilities and an improvement in our overall funding mix. Customer deposit growth in 2024 and 2025 has reduced our levels of borrowings and brokered deposits.

Interest income on an FTE basis (non-GAAP) remained relatively unchanged in 2025 compared to 2024 due to increased yield in the securities portfolio partially offset by yield declines in the loan portfolio. The average yield on securities increased 69 basis points compared to 2024 primarily due to the repositioning of $193.6 million of securities during 2024 and 2025. The average yield on loan balances decreased 22 basis points compared to 2024 due to lower interest rates. Average loan balances increased $221.2 million to $7.9 billion in 2025 compared to $7.7 billion in 2024. Overall, the FTE rate (non-GAAP) on interest-earning assets decreased 13 basis points compared to 2024.

Interest expense decreased $14.7 million to $166.4 million in 2025 compared to $181.1 million in 2024. The decrease in interest expense was primarily due to lower levels of borrowings and decreased interest rates. Average interest-bearing deposits

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increased $246.8 million to $5.7 billion in 2025 compared to $5.5 billion in 2024. Average borrowings decreased $141.5 million to $211.8 million in 2025 compared to $353.2 in 2024 primarily due to an increase in deposits. Overall, the cost of interest-bearing liabilities decreased 30 basis points in 2025 compared to 2024.

The following table sets forth for the periods presented a summary of the changes in interest earned and interest paid resulting from changes in volume and changes in rates:

(1)Nonaccruing loans are included in the daily average loan amounts outstanding.

(2)Tax-exempt income is on an FTE basis using the statutory federal corporate income tax rate of 21 percent.

(3)Taxable investment income is adjusted for the dividend-received deduction for equity securities.

(4)Changes to rate/volume are allocated to both rate and volume on a proportionate dollar basis.

Provision for Credit Losses

The provision for credit losses includes a provision for losses on loans and on unfunded loan commitments. The provision for credit losses fluctuates based on changes in loan balances, loan risk ratings, net loan charge-offs and recoveries, the macro environment and our CECL forecast.

The provision for credit losses increased $7.3 million to $7.4 million for 2025 compared to $0.1 million for 2024. The increase was primarily due to higher net loan charge-offs and a $2.9 million increase in the reserve for unfunded loan commitments due to higher unused commitments in the construction portfolio. Partially offsetting the increase in the provision for credit losses was a lower level of ACL primarily related to a reduction in loss rates, lower criticized and classified loans and a decrease in the specific reserve for loans individually evaluated. The provision for credit losses included $1.2 million for the reserve for unfunded commitments for 2025 compared to negative $1.7 million for 2024. Net loan charge-offs for 2025 were $14.5 million, or 0.18 percent of average loans, compared to $8.3 million, or 0.11 percent of average loans, for 2024. Refer to the Credit Quality section of this MD&A for further details.

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Noninterest Income

Noninterest income increased $2.9 million, or 6.0 percent, to $52.0 million compared to $49.1 million in 2024. The increase primarily related to lower security losses of $2.3 million in 2025 compared to $7.9 million in 2024 offset by a $3.5 million gain from the exchange offer for Visa Class B-1 common stock recognized in other noninterest income in 2024.

Noninterest Expense

Noninterest expense was well controlled with an increase of $7.8 million, or 3.6 percent, to $226.8 million compared to $218.9 million in 2024. Salaries and employee benefits increased $5.7 million during 2025 primarily due to annual merit increases, higher incentives and increased restricted stock expense. Occupancy increased $1.1 million in 2025 due to increased maintenance and utility costs. Other noninterest expense increased $1.1 million compared to 2024 primarily related to higher employee related costs and loan related expenses.

Provision for Income Taxes

The provision for income taxes was unchanged at $33.7 million in 2025 compared to $33.6 million in 2024. The effective tax rate, which is total tax expense as a percentage of income before taxes, decreased to 20.1 percent in 2025 compared to 20.4 percent in 2024. The decrease in the effective tax rate in 2025 compared to 2024 was primarily due to an increase in LIHTC, net of amortization. We have generated an annual effective tax rate that is less than the statutory rate of 21 percent due to benefits resulting from tax-exempt interest, excludable dividend income, tax-exempt income on Bank Owned Life Insurance, or BOLI, and tax benefits associated with LIHTC which is partially offset by the proportional amortization method, or PAM.

Financial Condition as of December 31, 2025

Total assets increased $213.0 million to $9.9 billion at December 31, 2025 compared to $9.7 billion at December 31, 2024. Total portfolio loans increased $329.0 million, or 4.3 percent, to $8.1 billion at December 31, 2025 compared to December 31, 2024. The commercial loan portfolio increased $244.9 million and the consumer loan portfolio increased $84.1 million compared to December 31, 2024.

Securities remained relatively flat at December 31, 2025 compared to December 31, 2024. The securities portfolio was in a net unrealized loss position of $34.9 million at December 31, 2025 compared to a net unrealized loss position of $71.7 million at December 31, 2024. The improvement in the net unrealized loss position of the securities portfolio was primarily due to a decline in interest rates from December 31, 2024.

Total deposits increased $175.7 million, or 2.3 percent, to $8.0 billion at December 31, 2025 compared to $7.8 billion at December 31, 2024. Customer deposits increased $220.5 million to $7.8 billion at December 31, 2025 compared to $7.6 billion at December 31, 2024. Brokered deposits decreased $44.8 million to $180.4 million at December 31, 2025 compared to $225.2 million at December 31, 2024.

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Total borrowings increased $15.0 million to $265.3 million at December 31, 2025 compared to $250.3 million at December 31, 2024.

Total shareholders’ equity increased by $83.6 million to $1.5 billion at December 31, 2025 compared to December 31, 2024. The increase was primarily due to net income of $134.2 million and other comprehensive income of $35.3 million offset by dividends of $53.0 million and repurchases of S&T common stock of $36.6 million which includes excise tax and commissions of $0.4 million. During the fourth quarter of 2025, 948,270 common shares were repurchased at an average price of $38.20 per share.

Securities Activity

We invest in various securities in order to maintain a source of liquidity, to satisfy various pledging requirements, to increase net interest income and as a tool of ALCO to reposition the balance sheet for interest rate risk purposes. Securities are subject to market risks that could negatively affect the level of liquidity available to us. Security purchases are subject to an investment policy approved annually by our Board of Directors and administered through ALCO and our treasury function. Our entire securities portfolio is classified as available for sale. The portfolio primarily consists of structured agency-backed, fixed-income securities with limited credit exposure. Total securities available for sale at December 31, 2025 remained relatively flat compared to December 31, 2024.

At December 31, 2025, our securities portfolio was in a net unrealized loss position of $34.9 million compared to a net unrealized loss position of $71.7 million at December 31, 2024. At December 31, 2025, our securities portfolio had gross unrealized losses of $42.4 million offset by $7.5 million in gross unrealized gains compared to December 31, 2024, when total gross unrealized losses were $72.7 million offset by gross unrealized gains of $1.0 million.

Management evaluates the securities portfolio to determine if an ACL is needed each quarter. We did not record an ACL related to the securities portfolio at December 31, 2025 or December 31, 2024. The unrealized losses on debt securities were primarily attributable to changes in interest rates and not related to the credit quality of these securities. All debt securities were determined to be investment grade and paying principal and interest according to the contractual terms of the security at December 31, 2025. We do not intend to sell and it is more likely than not that we will not be required to sell any of the securities in an unrealized loss position before recovery of their amortized cost. We did not recognize any impairment charges on our securities portfolio in 2025, 2024 or 2023.

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The following table sets forth the maturities of securities at December 31, 2025 and the weighted average yields of such securities. Taxable-equivalent adjustments for 2025 have been made in calculating yields on obligations of state and political subdivisions.

(1) Weighted-average yields are calculated on a taxable-equivalent basis using the federal statutory tax rate of 21 percent for 2025.

Loan Composition

The following table summarizes our loan portfolio as of the dates presented:

The loan portfolio represents the most significant source of interest income for us. The risk that borrowers will be unable to pay such obligations is inherent in the loan portfolio. Other conditions, such as downturns in the borrower’s industry or the overall economic climate, can significantly impact the borrower’s ability to pay.

We adhere to a General Lending Policy to maintain the quality of our loan portfolio. The policy delegates the authority to extend loans under specific guidelines and underwriting standards. The General Lending Policy is formulated by management and reviewed and ratified annually by the Board of Directors.

We attempt to limit our exposure to credit risk by diversifying our loan portfolio by segment, geography, collateral and industry and actively managing concentrations. When concentrations exist in certain segments, we assess the credit risk within those segments to determine if additional reserve is needed in the qualitative portion of the ACL. Total commercial loans represented 68.5 percent of total portfolio loans at December 31, 2025 compared to 68.2 percent at December 31, 2024. Within our commercial portfolio, the CRE and commercial construction portfolios combined comprised $4.0 billion, or 72.5 percent, of total commercial loans and 49.6 percent of total portfolio loans at December 31, 2025 compared to $3.7 billion, or 70.8 percent, of total commercial loans and 48.3 percent of total portfolio loans at December 31, 2024.

We lend primarily in Pennsylvania and the contiguous states of Ohio, New York, West Virginia, New Jersey, Delaware and Maryland. The majority of our commercial and consumer loans are made to businesses and individuals in these states resulting in a geographic concentration. We believe our knowledge of these markets outweighs the geographic concentration risk. Our operating knowledge at the local and regional level is derived from our front-line connection to the customer and our understanding of their businesses. We also have a portfolio management group that utilizes multiple data sources including

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customer information, publicly available data and subscription service data to assess risk on an on-going basis and strong overall risk management practices which help us understand and evaluate concentration risk. Our CRE and commercial construction portfolios have exposure outside of the primary states in which we operate of 3.5 percent of the combined portfolios and 1.7 percent of total portfolio loans at December 31, 2025 and 3.9 percent of the combined portfolios and 1.9 percent of total portfolio loans at December 31, 2024.

Total portfolio loans increased $329.0 million, or 4.2 percent, to $8.1 billion at December 31, 2025 compared to $7.7 billion at December 31, 2024. As of December 31, 2025, 60.0 percent of our total loans were variable rate loans and 40.0 percent were fixed rate loans compared to 62.0 percent variable rate loans and 38.0 percent fixed rate loans at December 31, 2024.

Commercial loans represented 68.5 percent of our total portfolio loans at December 31, 2025 and 68.2 percent at December 31, 2024. Commercial loans increased $244.9 million to $5.5 billion at December 31, 2025 compared to $5.3 billion at December 31, 2024 related to increases of $238.8 million in CRE and $27.2 million in commercial construction offset by a decrease of $21.1 million in C&I.

Consumer loans represented 31.5 percent of our total portfolio loans at December 31, 2025 and 31.8 percent at December 31, 2024. Consumer loans increased $84.1 million to $2.5 billion at December 31, 2025 compared to $2.5 billion at December 31, 2024 primarily due to an increase of $97.6 million in consumer real estate offset by a decrease of $13.5 million in consumer installment loans.

We originate traditional fixed rate mortgage loans and adjustable rate mortgages with a maximum amortization term of 30 years. The loan to value, or LTV, policy guideline is 80 percent for residential first lien mortgages. Higher LTV loans may be approved within unique program guidelines. We may originate home equity loans with a lien position that is second to unrelated third-party lenders, but normally only to the extent that the combined LTV considering both the first and second liens does not exceed 100 percent of the fair value of the property. Combo mortgage loans consisting of a residential first mortgage and a home equity second mortgage are also available.

We had historically originated and sold loans to the secondary market, primarily to Fannie Mae, in order to mitigate interest-rate risk associated with holding lower rate, long-term residential mortgages in the loan portfolio and to generate fee revenue from sales and servicing of the loans. Beginning in 2023, our strategy changed whereby we held more mortgages on our balance sheet versus selling these loans in the secondary market. This shift in strategy was due to pricing in the secondary mortgage market and the desire to shift the mix of our loan portfolio to more fixed rate loans. We continue to monitor our strategy and may shift back to selling more residential mortgages into the secondary market in future periods. At December 31, 2025, our servicing portfolio of mortgage loans that we originated and sold into the secondary market was $591.6 million compared to $648.9 million at December 31, 2024.

The following table presents the maturity of commercial and consumer loans outstanding as of December 31, 2025:

Off-Balance Sheet Arrangements

In the normal course of business, we offer off-balance sheet credit arrangements to enable our customers to meet their financing objectives. These instruments involve, to varying degrees, elements of credit and interest rate risk in excess of the amount recognized in the financial statements. Our exposure to credit loss, in the event the customer does not satisfy the terms of the agreement, equals the contractual amount of the obligation less the value of any collateral. We apply the same credit policies in making commitments and standby letters of credit that are used for the underwriting of loans to customers. Commitments generally have fixed expiration dates, annual renewals or other termination clauses and may require payment of a fee. Many of the commitments are expected to expire without being drawn upon, therefore, the total commitment amounts do not necessarily represent future cash requirements.

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The following table sets forth our commitments and letters of credit as of the dates presented:

See Note 16. Commitments and Contingencies in Part II, Item 8. Financial Statements and Supplementary Data of this Report for details on the allowance for credit losses on unfunded commitments.

Credit Quality

On a quarterly basis, criticized asset meetings are held to monitor all special mention and substandard loans greater than $1.5 million and all business banking special mention and substandard loans greater than $0.5 million to establish action plans for these loans. These loans typically represent the highest risk of loss to us. We monitor these loans through regular contact with the borrower, review of current financial information and other documentation, review of all loan or potential loan restructures or modifications and the regular reevaluation of assets held as collateral. We also have a quarterly criticized asset meeting for the retail portfolio to review delinquent and nonaccrual loans as well as individual portfolio reviews such as unsecured, private banking and first payment default loans.

Additional credit risk management practices include periodic loan reviews, at least annually, and updates of our lending policies and procedures to support sound underwriting practices and portfolio management through portfolio stress testing. Our business banking relationships are monitored through portfolio management software that identifies credit risk indicators. We have portfolio monitoring groups that perform annual reviews of all commercial and business banking relationships greater than $1.5 million and a quarterly review of our watch rated portfolio. Our credit risk review process serves to independently monitor credit quality and assess the effectiveness of credit risk management practices to provide oversight of all corporate lending activities. The credit risk review function has the primary responsibility for assessing commercial credit administration and credit decision functions of consumer and mortgage underwriting, as well as providing input to the loan risk rating process.

Our policy is to place loans in all categories in nonaccrual status when collection of interest or principal is doubtful or generally when interest or principal payments are 90 days or more past the contractual due date.

The following table presents delinquency and nonaccrual loans as of December 31:

Nonaccrual loans increased to $55.6 million at December 31, 2025 compared to $27.9 million at December 31, 2024. The increase in nonaccrual loans was primarily due to the addition of three commercial relationships totaling $25.3 million that were placed on nonaccrual during the three months ended December 31, 2025. A specific reserve of $1.6 million was added for one of the commercial relationships based on an updated collateral evaluation.

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Closed-end installment loans, amortizing loans secured by real estate and any other loans with payments scheduled monthly are reported past due when the borrower is in arrears two or more monthly payments. Other multi-payment obligations with payments scheduled other than monthly are reported past due when one scheduled payment is due and unpaid for 30 days or more. We monitor delinquency on a monthly basis, including early-stage delinquencies of 30 to 89 days past due for early identification of potential problem loans.

Allowance for Credit Losses

We maintain an ACL at a level determined to be adequate to absorb estimated expected credit losses within the loan portfolio over the contractual life of a loan that considers our historical loss experience, current conditions and forecasts of future economic conditions as of the balance sheet date. We develop and document a systematic ACL methodology based on the following portfolio segments: 1) CRE, 2) C&I, 3) Commercial Construction, 4) Business Banking, 5) Consumer Real Estate and 6) Other Consumer.

Our charge-off policy for commercial loans requires that loans and other obligations that are not collectible be promptly charged-off when the loss is confirmed, regardless of the delinquency status of the loan. We may elect to recognize a partial charge-off when management has determined that the value of collateral or present value of expected future cash flows is less than the remaining investment in the loan. A loan or obligation does not need to be charged-off, regardless of delinquency status, if (i) management has determined that sufficient collateral exists to protect the remaining loan balance and a strategy exists to liquidate the collateral, or (ii) management has determined that the present value of expected future cash flows is sufficient to protect the remaining loan balance. Management may also consider a number of other factors to determine when a charge-off is appropriate. These factors may include, but are not limited to:

•the status of a bankruptcy proceeding;

•the value of collateral and probability of successful liquidation; and/or

•the status of adverse proceedings or litigation that may result in collection.

Consumer loans are evaluated for charge-off after the loan becomes 90 days past due. Unsecured loans are fully charged off and secured loans are charged down to the estimated fair value of the collateral less the cost to sell.

The following table presents activity in the ACL for each of the three years presented below:

Net loan charge-offs for 2025 were $14.5 million, or 0.18 percent of average loans compared to $8.3 million, or 0.11 percent of average loans, for 2024. The most significant charge-offs during 2025 were to two CRE relationships totaling $7.2 million and two C&I relationships totaling $6.1 million. Offsetting loan charge-offs during 2025 were $3.6 million in recoveries compared to $3.9 million in recoveries in 2024.

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The following table summarizes net charge-offs as a percentage of average loans for the years presented:

The following is the ACL balance by portfolio segment as of December 31:

Significant to our ACL is a higher concentration of commercial loans. The ability of borrowers to repay commercial loans is dependent upon the success of their business and general economic conditions. Due to the greater potential for loss within our commercial portfolio, we monitor the commercial loan portfolio through an internal risk rating system. Loan risk ratings are assigned based upon the creditworthiness of the borrower and are reviewed on an ongoing basis according to our internal policies. Loans rated special mention or substandard have potential or well-defined weaknesses not generally found in high quality, performing loans and require attention from management to limit loss.

The ACL was $93.2 million, or 1.15 percent of total portfolio loans, at December 31, 2025 compared to $101.5 million, or 1.31 percent of total portfolio loans, at December 31, 2024. The decrease in the ACL of $8.3 million is primarily related to a reduction in loss rates, lower criticized and classified loans and a decrease in the specific reserve for loans individually evaluated.

Federal Home Loan Bank and Other Restricted Stock

At December 31, 2025, we held FHLB of Pittsburgh stock of $16.0 million compared to $15.2 million at December 31, 2024. This investment is carried at cost and evaluated for impairment based on the ultimate recoverability of the par value. We hold FHLB stock because we are a member of the FHLB of Pittsburgh. The FHLB requires members to purchase and hold a specified level of FHLB stock based upon the members’ asset values, level of borrowings and participation in other programs offered. Stock in the FHLB is non-marketable and is redeemable at the discretion of the FHLB. Members do not purchase stock in the FHLB for the same reasons that traditional equity investors acquire stock in an investor-owned enterprise. Rather, members purchase stock to obtain access to the products and services offered by the FHLB. Unlike equity securities of traditional for-profit enterprises, the stock of the FHLB does not provide its holders with an opportunity for capital appreciation because, by regulation, FHLB stock can only be purchased, redeemed and transferred at par value. We reviewed and evaluated the FHLB capital stock for impairment at December 31, 2025. The FHLB exceeds all required capital ratios. Additionally, we considered that the FHLB has been paying dividends and actively redeeming stock throughout 2025 and 2024. Accordingly, we believe sufficient evidence exists to conclude that no impairment existed at December 31, 2025.

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Deposits

Deposits are our primary source of funds. The following table presents the mix of deposits as of the dates presented:

The following table presents the composition of deposits as of the dates presented:

We have a strong core deposit base with noninterest-bearing demand deposits representing 27.2 percent of total deposits at December 31, 2025 compared to 28.1 percent of total deposits at December 31, 2024. Total deposits increased $175.7 million, or 2.3 percent, at December 31, 2025 compared to December 31, 2024. Total customer deposits increased $220.5 million, or 2.9 percent, from December 31, 2024 due to growth in certificates of deposit and money market. Total brokered deposits decreased $44.8 million from December 31, 2024 due to growth in customer deposits. Brokered deposits are an additional source of funds utilized by ALCO as a way to diversify funding sources, as well as manage our funding costs and structure.

As a member of the IntraFi network, we are able to offer our customers insurance coverage on interest-bearing demand, money market and certificate of deposit balances in excess of the FDIC insurance limits. IntraFi balances decreased $7.6 million to $317.3 million at December 31, 2025 compared to $324.8 million at December 31, 2024.

We have total uninsured deposits of $2.7 billion, or 33.7 percent of our total deposit base compared to $2.6 billion, or 33.5 percent, at December 31, 2024. Included in uninsured deposits is $333.6 million of fully collateralized, municipal deposits, or 4.2 percent of our total deposit base.

The daily average balance of deposits and rates paid on deposits are summarized in the following table for the years ended December 31:

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CDs greater than $250,000 accounted for 7.3 percent and 6.2 percent of total deposits at December 31, 2025 and December 31, 2024. These primarily represent deposit relationships with local customers in our market area.

Maturities of CDs of $250,000 or more outstanding at December 31, 2025 are summarized as follows:

Borrowings

Borrowings are an additional source of funding for us. Short-term borrowings are for terms under or equal to one year and are comprised of FHLB Advances. Long-term borrowings are for original terms greater than one year and are comprised of FHLB advances and finance leases. Total borrowings were $265.3 million at December 31, 2025 compared to $250.3 million at December 31, 2024.

Information pertaining to short-term borrowings is summarized in the table below for the years ended December 31, 2025 and December 31, 2024.

Information for long-term borrowings and junior subordinated debt securities is summarized in the tables below for the years ended December 31, 2025 and December 31, 2024.

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Wealth Management Assets

The fair value of the S&T Bank Wealth Management assets under administration, which are not accounted for as part of our assets, was $2.1 billion at December 31, 2025 and $2.0 billion at December 31, 2024. S&T Bank Wealth Management consists of S&T Trust which acts as a fiduciary by managing wealth for individuals and families and S&T Financial Services offers retirement and financial planning services. At December 31, 2025, assets under administration consisted of $0.6 billion in S&T Trust and $1.5 billion in S&T Financial Services compared to $0.7 billion in S&T Trust and $1.3 billion in S&T Financial Services at December 31, 2024.

Liquidity and Capital Resources

Liquidity is defined as a financial institution’s ability to meet its cash and collateral obligations at a reasonable cost. Our primary future cash needs are centered on the ability to (i) satisfy the financial needs of depositors who may want to withdraw funds or of borrowers needing to access funds to meet their credit needs and (ii) to meet our future cash commitments under contractual obligations with third parties. In order to manage liquidity risk, our Board of Directors has delegated authority to ALCO for the formulation, implementation and oversight of liquidity risk management for S&T. ALCO’s goal is to maintain adequate levels of liquidity at a reasonable cost to meet funding needs in both a normal operating environment and for potential liquidity stress events. ALCO monitors and manages liquidity through various ratios, reviewing cash flow projections, performing stress tests and having a detailed contingency funding plan. ALCO policy guidelines define graduated risk tolerance levels. If our liquidity position moves to a level that has been defined as high risk, specific actions are required, such as increased monitoring or the development of an action plan to reduce the risk position.

Our primary funding and liquidity source is a stable customer deposit base. We believe S&T has the ability to retain existing deposits and attract new deposits, mitigating any funding dependency on other more volatile funding sources. Refer to the "Financial Condition as of December 31, 2025 - Deposits" section of this MD&A, for additional discussion on deposits. Although deposits are the primary source of funds, we have identified various other funding sources that can be used as part of our normal funding program. Additional funding sources accessible to S&T include borrowing availability at the FHLB, Federal Reserve Discount Window through the Borrower-in-Custody Program, federal funds lines with other financial institutions and the brokered deposit market.

Available borrowing capacity exceeds uninsured deposits of $2.7 billion at December 31, 2025 and $2.6 billion at December 31, 2024. The following table summarizes borrowing funding sources available as of the dates presented:

At December 31, 2025, we had available borrowing capacity of $3.9 billion, $2.1 billion at the Federal Reserve and $1.8 billion at the FHLB of Pittsburgh. We believe that these funding sources will provide adequate resources to fund our short-term and long-term operating and financing needs. In addition, our ability to access capital markets provides additional sources of funding with respect to strategic investing opportunities. Our access to and the availability of funds in the future will be affected by many factors, including, but not limited to our financial condition and prospects, the liquidity of the overall capital markets and the current state of the economy.

In the normal course of business, we enter into various contractual obligations which require future payments that could impact our liquidity and capital resources. We also utilize interest rate swaps to add stability and manage exposure to interest rate movements, under which we are required to either receive cash from, or pay cash to, counterparties depending on changes in interest rates. Derivative contracts are carried at fair value representing the net present value of expected future cash receipts or payments based on market rates as of the balance sheet date.

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The following table summarizes our material contractual obligations as of December 31, 2025:

(1)Excludes interest

An important component of our ability to effectively respond to potential liquidity stress events is maintaining a cushion of highly liquid assets. Highly liquid assets are those that can be converted to cash quickly, with little or no loss in value, to meet financial obligations. ALCO policy guidelines define a ratio of highly liquid assets to total assets by graduated risk tolerance levels of minimal, moderate and high. At December 31, 2025, S&T Bank had $852.2 million in highly liquid assets which consisted primarily of $105.2 million in interest-bearing deposits with banks and $746.0 million in unpledged securities. This resulted in a highly liquid assets to total assets ratio of 8.6 percent at December 31, 2025 compared to 9.7 percent at December 31, 2024. Refer to Note 12. Tax Credit Equity Investments, Note 13. Deposits, Note 14. Short Term Borrowings, Note 15. Long Term Borrowings and Subordinated Debt and Note 7. Right-Of-Use Assets and Lease Liabilities to the consolidated financial statements included in Part II, Item 8. Financial Statements and Supplementary Data and the Deposits and Borrowings section of this MD&A, for more details.

Capital Resources

Shareholders’ equity increased $83.6 million, or 6.1 percent, to $1.5 billion at December 31, 2025 compared to $1.4 billion at December 31, 2024. The increase was primarily due to net income of $134.2 million and other comprehensive income of $35.3 million partially offset by dividends of $53.0 million and share repurchases of $36.6 million. The other comprehensive income was primarily due to a $28.9 million improvement in unrealized losses on our available-for-sale debt securities, net of tax and an improvement of $5.9 million in unrealized losses on our interest rate swaps, net of tax.

We continue to maintain a strong capital position with a leverage ratio of 12.18 percent as compared to the regulatory guideline of 5.00 percent to be well-capitalized and a risk-based Common Equity Tier 1 ratio of 14.32 percent compared to the regulatory guideline of 6.50 percent to be well-capitalized. Our risk-based Tier 1 and Total capital ratios were 14.62 percent and 16.19 percent which places us above the federal bank regulatory agencies’ well-capitalized guidelines of 8.00 percent and 10.00 percent. Our ratios are also above the required minimum ratios after the capital conservation buffer, discussed further below, of common equity tier 1 risk-based capital ratio greater than 7.00 percent, tier 1 risk-based capital ratio greater than 8.50 percent and a total risk-based capital ratio greater than 10.50 percent. We believe that we have the ability to raise additional capital, if necessary.

On March 27, 2020, the regulators issued interim final rule, or IFR, “Regulatory Capital Rule: Revised Transition of the Current Expected Credit Losses Methodology for Allowances” in response to the disrupted economic activity from the spread of COVID-19. The IFR provides financial institutions that adopt CECL during 2020 with the option to delay for two years the estimated impact of CECL on regulatory capital, followed by a three-year transition period to phase out the aggregate amount of the capital benefit provided by the initial two-year delay (“five-year transition”). We adopted CECL effective January 1, 2020 and elected to implement the five-year transition. As of December 31, 2025 we are fully transitioned.

Banking organizations are required to maintain a capital conservation buffer composed of common equity tier 1 capital in an amount greater than 2.50 percent of total risk-weighted assets. Banking organizations must maintain a common equity tier 1 risk-based capital ratio greater than 7.00 percent, a tier 1 risk-based capital ratio greater than 8.50 percent and a total risk-based capital ratio greater than 10.50 percent; otherwise, it will be subject to restrictions on capital distributions and discretionary bonus payments. The minimum capital requirements plus the capital conservation buffer exceeds the regulatory capital ratios required for an insured depository institution to be well-capitalized under the FDIC's prompt corrective action framework.

Federal regulators periodically propose amendments to the regulatory capital rules and the related regulatory framework and consider changes to the capital standards that could significantly increase the amount of capital needed to meet applicable standards. The timing of adoption, ultimate form and effect of any such proposed amendments cannot be predicted.

We have filed a shelf registration statement on Form S-3 under the Securities Act of 1933 as amended, with the SEC, which allows for the issuance of a variety of securities including debt and capital securities, preferred and common stock and warrants. We may use the proceeds from the sale of securities for general corporate purposes which could include investments

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at the holding company level, investing in, or extending credit to subsidiaries, possible acquisitions and stock repurchases. As of December 31, 2025, we had not issued any securities pursuant to the shelf registration statement.

Inflation

Inflation can have a significant impact on interest rates and, accordingly, can impact our financial performance. Inflation can influence our asset growth, deposits, noninterest income and expense and credit quality. As a result, we closely monitor the rate of inflation in the economy. We do so by analyzing our capability to respond to changing interest rates and our ability to manage noninterest income and expense. We monitor the mix of interest-rate sensitive assets and liabilities through ALCO in order to manage the impact of inflation and the level of interest rates on net interest income. We also manage the effects of inflation on S&T by reviewing the prices of our products and services, by introducing new products and services and by controlling overhead expenses. Additionally, management is aware of the potential impacts that inflation can have on our loan portfolio and our customer's ability to operate their businesses. We seek to minimize the various inflationary inputs through a robust annual review process and sensitivity analysis when considering extensions of credit. Additionally, we leverage our internal credit risk review in support of the current economic cycle. We continuously monitor our portfolio for potential and emerging risks. See Risk Factors in Item 1A for further information regarding the impact of inflation on the economy and on S&T.

Market risk is defined as the degree to which changes in interest rates, foreign exchange rates, commodity prices or equity prices can adversely affect a financial institution’s earnings or capital. For most financial institutions, including S&T, market risk primarily reflects exposures to changes in interest rates. Interest rate fluctuations affect earnings by changing net interest income and other interest-sensitive income and expense levels. Interest rate changes also affect capital by changing the net present value of a bank’s future cash flows, and the cash flows themselves, as rates change. Accepting this risk is a normal part of banking and can be an important source of profitability and enhancing shareholder value. However, excessive interest rate risk can threaten a bank’s earnings, capital, liquidity and solvency. Our sensitivity to changes in interest rate movements is continually monitored by ALCO. ALCO monitors and manages market risk through rate shock analyses, economic value of equity, or EVE, analyses and by performing stress tests and simulations to mitigate earnings and market value fluctuations due to changes in interest rates.

Rate shock analyses results are compared to a base case to provide an estimate of the impact that market rate changes may have on 12 and 24 months of pretax net interest income. The base case and rate shock analyses are performed on a static balance sheet. A static balance sheet is a no growth balance sheet in which all maturing and/or repricing cash flows are reinvested in the same product at the existing product spread. Rate shock analyses assume an immediate parallel shift in market interest rates and also include management assumptions regarding the impact of interest rate changes on non-maturity deposit products (noninterest-bearing demand, interest-bearing demand, money market and savings) and changes in the prepayment behavior of loans and securities with optionality. S&T policy guidelines limit the change in pretax net interest income over 12 and 24 month horizons using rate shocks in increments of +/- 100 basis points. Policy guidelines define the percentage change in pretax net interest income by graduated risk tolerance levels of minimal, moderate and high.

In order to monitor interest rate risk beyond the 24 month time horizon of rate shocks on pretax net interest income, we also perform EVE analyses. EVE represents the present value of all asset cash flows minus the present value of all liability cash flows. EVE change results are compared to a base case to determine the impact that market rate changes may have on our EVE. As with rate shock analyses on pretax net interest income, EVE analyses incorporate management assumptions regarding prepayment behavior of fixed rate loans and securities with optionality and the behavior and value of non-maturity deposit products. S&T policy guidelines limit the change in EVE using rate shocks in increments of +/- 100 basis points. Policy guidelines define the percentage change in EVE by graduated risk tolerance levels of minimal, moderate and high.

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S&T BANCORP, INC. AND SUBSIDIARIES

The table below reflects the rate shock analyses results for the 1-12 and 13-24 month periods of pretax net interest income and EVE.