NBT BANCORP INC (NBTB)

ITEM 2.

MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The purpose of this discussion and analysis is to provide a concise description of the consolidated financial condition and results of operations of NBT Bancorp Inc. (“NBT”) and its wholly-owned subsidiaries, including NBT Bank, National Association (the “Bank”), NBT Financial Services, Inc. (“NBT Financial”) and NBT Holdings, Inc. (“NBT Holdings”) (collectively referred to herein as the “Company”). When references to “NBT,” “we,” “our,” “us,” and “the Company” are made in this report, we mean NBT Bancorp Inc. and our consolidated subsidiaries, unless the context indicates that we refer only to the parent company, NBT Bancorp Inc. When we refer to the “Bank” in this report, we mean our only bank subsidiary, NBT Bank, National Association, and its subsidiaries. This discussion will focus on results of operations and financial condition, including capital resources and asset/liability management. Reference should be made to the Company’s consolidated financial statements and footnotes thereto included in this Form 10‑Q as well as to the Company’s Annual Report on Form 10‑K for the year ended December 31, 2025 for an understanding of the following discussion and analysis. Operating results for the three and six months ended June 30, 2026 are not necessarily indicative of the results of the full year ending December 31, 2026 or any future period.

Forward-Looking Statements

Certain statements in this filing and future filings by the Company with the SEC, in the Company’s press releases or other public or stockholder communications or in oral statements made with the approval of an authorized executive officer, contain forward-looking statements, as defined in the Private Securities Litigation Reform Act of 1995. These statements may be identified by the use of phrases such as “anticipate,” “believe,” “expect,” “forecasts,” “projects,” “will,” “can,” “would,” “should,” “could,” “may,” or other similar terms. There are a number of factors, many of which are beyond the Company’s control, that could cause actual results to differ materially from those contemplated by any forward-looking statements. Factors that may cause actual results to differ materially from those contemplated by such forward-looking statements include, among others, the following possibilities: (1) local, regional, national and international economic conditions, including actual or potential stress in the banking industry, and the impact they may have on the Company and its customers, and the Company’s assessment of that impact; (2) changes in the level of nonperforming assets and charge-offs; (3) changes in estimates of future reserve requirements based upon the periodic review thereof under relevant regulatory and accounting requirements; (4) the effects of and changes in trade and monetary and fiscal policies and laws, including the interest rate policies of the FRB and international trade disputes (including threatened or implemented tariffs imposed by the U.S. and threatened or implemented tariffs imposed by foreign countries in retaliation); (5) inflation, interest rate, securities market and monetary fluctuations; (6) political instability; (7) acts of war, including international military conflicts, or terrorism; (8) the timely development and acceptance of new products and services and the perceived overall value of these products and services by users; (9) changes in consumer spending, borrowing and saving habits; (10) changes in the financial performance and/or condition of the Company’s borrowers; (11) technological changes; (12) acquisition and integration of acquired businesses; (13) the ability to increase market share and control expenses; (14) changes in the competitive environment among financial holding companies; (15) the effect of changes in laws and regulations (including laws and regulations concerning taxes, banking, securities and insurance) with which the Company and its subsidiaries must comply, including those under the Dodd-Frank Act, and the Economic Growth, Regulatory Relief, and Consumer Protection Act of 2018; (16) the effect of changes in accounting policies and practices, as may be adopted by the regulatory agencies, as well as the Public Company Accounting Oversight Board, the Financial Accounting Standards Board and other accounting standard setters; (17) changes in the Company’s organization, compensation and benefit plans; (18) the costs and effects of legal and regulatory developments, including the resolution of legal proceedings or regulatory or other governmental inquiries, and the results of regulatory examinations or reviews; (19) greater than expected costs or difficulties related to the integration of new products and lines of business; and (20) the Company’s success at managing the risks involved in the foregoing items.

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The Company cautions readers not to place undue reliance on any forward-looking statements, which speak only as of the date on which they are made, and advises readers that various factors, including, but not limited to, those described above and other factors discussed in the Company’s annual and quarterly reports previously filed with the SEC, could affect the Company’s financial performance and could cause the Company’s actual results or circumstances for future periods to differ materially from those anticipated or projected.

Unless required by law, the Company does not undertake, and specifically disclaims any obligations to, publicly release any revisions that may be made to any forward-looking statements to reflect the occurrence of anticipated or unanticipated events or circumstances after the date of such statements.

Non-GAAP Measures

This Quarterly Report on Form 10-Q contains financial information determined by methods other than in accordance with GAAP. Where non-GAAP disclosures are used in this Form 10-Q, the comparable GAAP measure, as well as a reconciliation to the comparable GAAP measure, is provided in the accompanying tables. Management believes that these non-GAAP measures provide useful information that is important to an understanding of the results of the Company’s core business as well as provide information standard in the financial institution industry. Non-GAAP measures should not be considered a substitute for financial measures determined in accordance with GAAP and investors should consider the Company’s performance and financial condition as reported under GAAP and all other relevant information when assessing the performance or financial condition of the Company. Amounts previously reported in the consolidated financial statements are reclassified whenever necessary to conform to current period presentation.

Critical Accounting Estimates

SEC guidance requires disclosure of “critical accounting estimates.” The SEC defines “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 the financial condition or results of operations of the registrant. The Company follows financial accounting and reporting policies that are in accordance with GAAP. The more significant of these policies are summarized in Note 1 to the consolidated financial statements presented in our 2025 Annual Report on Form 10-K. Management has reviewed the application of these estimates with the Audit Committee of NBT’s Board of Directors. The allowance for credit losses and unfunded commitments policies are deemed to meet the SEC’s definition of a critical accounting estimate.

Allowance for Credit Losses and Unfunded Commitments

The allowance for credit losses consists of the allowance for credit losses and the allowance for losses on unfunded commitments. The measurement of CECL on financial instruments requires an estimate of the credit losses expected over the life of an exposure (or pool of exposures). The estimate of expected credit losses under the CECL methodology is based on relevant information about past events, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amounts. Historical loss experience is generally the starting point for estimating expected credit losses. The Company then considers whether the historical loss experience should be adjusted for asset-specific risk characteristics or current conditions at the reporting date that did not exist over the period from which historical experience was used. Finally, the Company considers forecasts about future economic conditions that are reasonable and supportable. The allowance for credit losses for loans, as reported in our consolidated statements of financial condition, is adjusted by an expense for credit losses, which is recognized in earnings, and reduced by the charge-off of loan amounts, net of recoveries. The allowance for losses on unfunded commitments represents the expected credit losses on off-balance sheet commitments such as unfunded commitments to extend credit and standby letters of credit. However, a liability is not recognized for commitments unconditionally cancellable by the Company. The allowance for losses on unfunded commitments is determined by estimating future draws and applying the expected loss rates on those draws.

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Management of the Company considers the accounting policy relating to the allowance for credit losses to be a critical accounting estimate given the uncertainty in evaluating the level of the allowance required to cover management’s estimate of all expected credit losses over the expected contractual life of our loan portfolio. Determining the appropriateness of the allowance is complex and requires judgment by management about the effect of matters that are inherently uncertain. Subsequent evaluations of the then-existing loan portfolio, in light of the factors then prevailing, may result in significant changes in the allowance for credit losses in those future periods. While management’s current evaluation of the allowance for credit losses indicates that the allowance is appropriate, the allowance may need to be increased under adversely different conditions or assumptions. The impact of utilizing the CECL methodology to calculate the reserve for credit losses will be significantly influenced by the composition, characteristics and quality of our loan portfolio, as well as the prevailing economic conditions and forecasts utilized. Material changes to these and other relevant factors may result in greater volatility to the reserve for credit losses, and therefore, greater volatility to our reported earnings.

One of the most significant judgments involved in estimating the Company’s allowance for credit losses relates to the macroeconomic forecasts used to estimate expected credit losses over the forecast period. At June 30, 2026, the weightings were 60%, 5% and 35% for the baseline, upside and downside economic forecast scenarios, respectively. The baseline outlook reflected an economic environment where the northeast unemployment rate increases from 4.46% in the second quarter of 2026 to 4.65% by the end of the forecast period, with a peak northeast unemployment rate of 4.69% in the second quarter of 2027. National GDP annualized growth (on a quarterly basis) is expected to start the third quarter of 2026 at approximately 1.95% and decrease to 1.93% by the end of the forecast period. Key assumptions in the baseline economic outlook included the Federal Reserve keeping their policy rate in the current range of 3.50%-3.75% and the economy remaining at full employment. The alternative upside scenario assumes improved economic conditions from the baseline outlook. Under this scenario, northeast unemployment falls from 4.46% in the second quarter of 2026 to 3.85% in the third quarter of 2027 an

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

The purpose of this discussion and analysis is to provide a concise description of the consolidated financial condition and results of operations of NBT Bancorp Inc. (“NBT”) and its wholly-owned
subsidiaries, including NBT Bank, National Association (the “Bank”), NBT Financial Services, Inc. (“NBT Financial”) and NBT Holdings, Inc. (“NBT Holdings”) (collectively referred to herein as the “Company”). When references to “NBT,” “we,” “our,”
“us,” and “the Company” are made in this report, we mean NBT Bancorp Inc. and our consolidated subsidiaries, unless the context indicates that we refer only to the parent company, NBT Bancorp Inc. When we refer to the “Bank” in this report, we
mean our only bank subsidiary, NBT Bank, National Association, and its subsidiaries. This discussion will focus on results of operations for the fiscal years ended December 31, 2025, 2024 and 2023 and financial condition as of December 31, 2025
and 2024, including capital resources and asset/liability management. This discussion and analysis should be read in conjunction with the Company’s consolidated financial statements and related notes.

Forward-Looking Statements

Certain statements in this filing and future filings by the Company with the SEC, in the Company’s press releases or other public or stockholder communications or in oral statements made with the approval of an
authorized executive officer, contain forward-looking statements, as defined in the Private Securities Litigation Reform Act of 1995. These statements may be identified by the use of phrases such as “anticipate,” “believe,” “expect,” “forecasts,”
“projects,” “will,” “can,” “would,” “should,” “could,” “may,” or other similar terms. There are a number of factors, many of which are beyond the Company’s control, that could cause actual results to differ materially from those contemplated by
the forward-looking statements. The discussion in Item 1A. Risk Factors lists some of the factors that may cause actual results to differ materially from those contemplated by any forward-looking statements, and such discussion is incorporated
into this discussion by reference.

The Company cautions readers not to place undue reliance on any forward-looking statements, which speak only as of the date on which they are made, and advises readers that various factors,
including, but not limited to, those described above and other factors discussed in the Company’s annual and quarterly reports previously filed with the SEC, could affect the Company’s financial performance and could cause the Company’s actual
results or circumstances for future periods to differ materially from those anticipated or projected.

Unless required by law, the Company does not undertake, and specifically disclaims any obligations to, publicly release any revisions that may be made to any forward-looking statements to reflect
the occurrence of anticipated or unanticipated events or circumstances after the date of such statements.

General

NBT Bancorp Inc. is a registered financial holding company headquartered in Norwich, NY, with total assets of $16.00 billion at December 31, 2025. The Company’s business, primarily conducted through
the Bank and its full-service retirement plan administration and recordkeeping subsidiary and full-service regional insurance agency subsidiary, consists of providing commercial banking, retail banking and wealth management services primarily to
customers in its market area, which includes upstate New York, northeastern Pennsylvania, southern New Hampshire, western Massachusetts, Vermont, southern Maine and central and northwestern Connecticut. The Company has been, and intends to
continue to be, a community-oriented financial institution offering a variety of financial services. The Company’s business philosophy is to operate as a community bank with local decision-making, providing a broad array of banking and financial
services to retail, commercial and municipal customers. The financial review that follows focuses on the factors affecting the consolidated financial condition and results of operations of the Company and its wholly-owned subsidiaries, the Bank,
NBT Financial and NBT Holdings during 2025 and, in summary form, the preceding two years. NIM is presented in this discussion on an FTE basis. Average balances discussed are daily averages unless otherwise described. The audited consolidated
financial statements and related notes as of December 31, 2025 and 2024 and for each of the years in the three-year period ended December 31, 2025 should be read in conjunction with this review.

Critical Accounting Policies

The SEC defines critical accounting policies as accounting policies that are most important to a company’s financial results and condition. These policies are often subjective and require management to make
estimates about uncertain matters. The accounting and reporting policies followed by the Company conform, in all material respects, to accounting principles in accordance with GAAP and to general practices within the financial services industry.
In the course of normal business activity, management must select and apply many accounting policies and methodologies and make estimates and assumptions that lead to the financial results presented in the Company’s consolidated financial
statements and accompanying notes. There are uncertainties inherent in making these estimates and assumptions, which could materially affect the Company’s results of operations and financial position.

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Management considers accounting estimates to be critical to reported financial results if (i) the accounting estimates require management to make assumptions about matters that are highly uncertain,
and (ii) different estimates that management reasonably could have used for the accounting estimate in the current period, or changes in the accounting estimate that are reasonably likely to occur from period to period, could have a material
impact on the Company’s financial statements. Management considers the accounting policies relating to the allowance for credit losses (“allowance”, or “ACL”) and the determination of fair values for acquired assets and assumed liabilities in a
business combination, including intangible assets such as goodwill, to be critical accounting policies because of the uncertainty and subjectivity involved in these policies and the material effect that estimates related to these areas can have
on the Company’s results of operations.

The Company’s methodology for estimating the allowance considers available relevant information about the collectability of cash flows, including information about past events, current conditions,
and reasonable and supportable forecasts. Refer to Note 1 and Note 6 to the consolidated financial statements included elsewhere in this report.

Goodwill represents the cost of the acquired business in excess of the fair value of the related net assets acquired. Following a merger, the determination of fair values for acquired assets and
assumed liabilities, including intangible assets such as goodwill, becomes critical. All acquired assets, including goodwill and other intangible assets, and assumed liabilities in purchase acquisitions are recorded at fair value as of the
acquisition date. The Company expenses all acquisition-related costs as incurred as required by ASC Topic 805, “Business Combinations.”

The determination of fair values for acquired loans in a business combination is a significant aspect of our financial reporting process. The valuation of acquired loans relied on a discounted cash
flow approach applied on a pooled basis, utilizing a forecast of principal and interest payments. This methodology segmented the acquired loan portfolio by loan type, term, interest rate, payment frequency and payment, and incorporated specific
key valuation assumptions, encompassing prepayment speeds, PD, LGD, and the discount rate to ascertain the fair value of these assets. Given the inherent subjectivity and reliance on future cash flows and market conditions, this process involves
considerable judgment and estimation uncertainty.

The Company conducts an annual review of goodwill impairment and conducts quarterly analyses to identify any events that may necessitate an interim assessment. The Company initially undertakes a
qualitative evaluation of goodwill to ascertain whether certain events or circumstances indicate a likelihood that the fair value of a reporting unit is less than its carrying amount. This qualitative evaluation demands considerable managerial
discretion, and if it suggests that the fair value of a reporting unit is unlikely to be less than the carrying value, no quantitative analysis is required. Inputs for this qualitative analysis requiring managerial judgment encompass
macroeconomic conditions, industry and market conditions, the financial performance of the reporting unit, and other pertinent events influencing the fair value of the reporting unit.

For information on the Company’s significant accounting policies and to gain a greater understanding of how the Company’s financial performance is reported, refer to Note 1 to the consolidated
financial statements included elsewhere in this report.

Critical Accounting Estimates

SEC guidance requires disclosure of “critical accounting estimates.” The SEC defines “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 the financial condition or results of operations of the registrant. The Company follows financial accounting and reporting policies that are in
accordance with GAAP. Management has reviewed the application of these estimates with the Audit Committee of NBT’s Board of Directors. The allowance for credit losses and unfunded commitments policies are deemed to meet the SEC’s definition of a
critical accounting estimate.

Allowance for Credit Losses and Unfunded Commitments

The allowance for credit losses consists of the allowance for credit losses and the allowance for losses on unfunded commitments. The measurement of CECL on financial instruments requires an
estimate of the credit losses expected over the life of an exposure (or pool of exposures). The estimate of expected credit losses under the CECL methodology is based on relevant information about past events, current conditions, and reasonable
and supportable forecasts that affect the collectability of the reported amounts. Historical loss experience is generally the starting point for estimating expected credit losses. The Company then considers whether the historical loss experience
should be adjusted for asset-specific risk characteristics or current conditions at the reporting date that did not exist over the period from which historical experience was used. Finally, the Company considers forecasts about future economic
conditions that are reasonable and supportable. The allowance for credit losses for loans, as reported in our consolidated statements of financial condition, is adjusted by an expense for credit losses, which is recognized in earnings, and
reduced by the charge-off of loan amounts, net of recoveries. The allowance for losses on unfunded commitments represents the expected credit losses on off-balance sheet commitments such as unfunded commitments to extend credit and standby
letters of credit. However, a liability is not recognized for commitments unconditionally cancellable by the Company. The allowance for losses on unfunded commitments is determined by estimating future draws and applying the expected loss rates
on those draws.

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Management of the Company considers the accounting policy relating to the allowance for credit losses to be a critical accounti

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