FIRST BUSEY CORP /NV/

To the Stockholders and the Board of Directors of First Busey Corporation and Subsidiaries

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of First Busey Corporation and Subsidiaries (the Company) as of December 31, 2025 and 2024, the related consolidated statements of income, comprehensive income, stockholders’ equity and cash flows for each of the three years in the period ended December 31, 2025, and the related notes to the consolidated financial statements (collectively, the financial statements). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2025 and 2024, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2025, in conformity with accounting principles generally accepted in the United States of America.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company’s internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control — Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission in 2013, and our report dated February 26, 2026, expressed an unqualified opinion on the effectiveness of the Company’s internal control over financial reporting.

Basis for Opinion

These financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matters

The critical audit matters communicated below are matters arising from the current period audit of the financial statements that were communicated or required to be communicated to the audit committee and that: (1) relate to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the financial statements, taken as a whole, and we are not, by communicating the critical audit matters below, providing separate opinions on the critical audit matters or on the accounts or disclosures to which they relate.

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Allowance for Credit Losses on Loans ‑ Adjustments to Historical Loss Factors

As described in Note 1 to the financial statements, the allowance for credit losses is measured on a collective (pool) loan basis when similar risk characteristics exist. On a case by case basis, a loan may be evaluated on an individual basis based on disparate risk characteristics. The measurement of expected credit losses is based on relevant information about past events, including historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the amortized cost basis. Adjustments to historical loss information are made for differences in current loan specific risk characteristics such as differences in underwriting standards, portfolio mix, delinquency level, or term as well as for changes in environmental conditions such as changes in unemployment rates, property values, and other relevant factors. The calculation also contemplates that Busey may not be able to make or obtain such forecasts for the entire life of the financial assets and requires a reversion to historical credit loss information. As described in Note 4 to the financial statements, Management estimates the allowance for credit losses balance using relevant available information from internal and external sources relating to past events, current conditions, and reasonable and supportable forecasts. Historical credit loss experience provides the basis for the estimation of expected credit losses. The allowance for credit losses consists of three components: (1) specific allocations/individual reserves; (2) quantitative reserves; and (3) qualitative reserves.

We identified the adjustments to historical loss factors, including the forecasting and qualitative reserves components of the allowance for credit losses on pooled loans, as a critical audit matter, as auditing the underlying support and adjustments required significant auditor judgment as amounts determined or utilized by management rely on analysis that is highly subjective and includes significant estimation uncertainty.

Our audit procedures related to the adjustments to historical loss factors within the allowance for credit losses on pooled loans include the following, among others:

•We obtained an understanding of the relevant controls related to the allowance for credit losses on pooled loans and tested such controls for design and operating effectiveness, including those over approval of key data inputs including forecasted economic scenarios, loss drivers and qualitative factors (such as economic and business conditions) including validation of underlying data, qualitative reserve component in the calculation of the allowance for credit losses and tested such controls for design and operating effectiveness.

•We tested the completeness and accuracy of data used by management in determining the inputs to the forecasted economic scenarios and qualitative reserve component including testing the supporting data for agreement to internal or external source data.

•We tested management’s forecasts of future economic loss drivers, which include national unemployment, change in national gross domestic product, and change in National Housing Price Index, by comparing these forecasts to external and internal information sources.

•We tested management’s conclusions regarding the appropriateness of the qualitative reserve component, including magnitude and directional consistency of changes in the level of adjustments to historical loss information between periods and evaluating whether management’s conclusions were reasonable and consistent with Company provided internal data and external independent data, including data related to current and forecasted periods, to historical loss factors included in the allowance for credit losses calculation.

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Business Combination ‑ Fair Value of Acquired Loans

As described in Notes 1 and 2 to the consolidated financial statements, on March 1, 2025, the Company completed its acquisition of CrossFirst Bankshares. The CrossFirst acquisition was accounted for using the acquisition method of accounting and, accordingly, assets acquired, liabilities assumed, and consideration exchanged were recorded at estimated fair values as of March 1, 2025, the date of acquisition. Subsequent to the acquisition, fair value adjustments of $1.9 million have been recorded, as additional information and valuations became available. As the total consideration paid for CrossFirst exceeded the estimated fair value of net assets acquired, goodwill of $49.5 million was recorded as a result of the acquisition. Estimated fair values for the loan portfolio acquired in the CrossFirst acquisition included adjustments to certain receivables that were not considered purchase credit deteriorated (PCD) as of the acquisition date. These loans did not show signs of deterioration since origination, and therefore, at the acquisition date, were not subject to the guidance related to PCD loans. Receivables acquired in the CrossFirst acquisition that were not subject to these requirements included non‑PCD loans with a fair value of $4.70 billion and gross contractual amounts receivable of $4.79 billion. The fair value of PCD loans at acquisition was $1.33 billion compared to a contractual value of $1.54 billion.

We identified the fair value of acquired PCD and non-PCD loans as a critical audit matter, because of the judgments necessary to determine the fair value of the loan portfolio acquired, the high degree of auditor judgment involved and the extensive audit effort involved in testing management estimates and assumptions related to classification and valuation methodology of PCD loans and discount rates on non-PCD loans.

Our audit procedures related to the valuation of the acquired loan portfolio included the following, among others:

•We obtained an understanding of the relevant controls related to the business combination, including the valuation of the acquired loan portfolio and management’s development of significant assumptions, and tested such controls for design and operating effectiveness.

•We obtained the valuation report prepared by a third party engaged by management, and gained an understanding of the valuation methodology applied to PCD and non‑PCD loans, as well as key inputs and assumptions.

•We tested the completeness and accuracy of data inputs provided by management and utilized in the calculation performed by the third‑party specialist.

•We utilized internal valuation specialists to assist in evaluating the discount rate on non‑PCD loans.

•We evaluated the appropriateness of management’s classification of PCD loans, and tested the propriety of the fair value credit marks associated with these loans.

/s/RSM US LLP

We or our predecessor firms have served as the Company’s auditor since at least 1980; however, an earlier year could not be established.

Des Moines, Iowa

February 26, 2026

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