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 its subsidiaries (the Company) as of December 31, 2024 and 2023, the related consolidated statements of income, comprehensive income (loss), stockholders' equity and cash flows for each of the three years in the period ended December 31, 2024, 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, 2024 and 2023, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2024, 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, 2024, 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 27, 2025, 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 matter communicated below is a matter arising from the current period audit of the financial statements that was communicated or required to be communicated to the audit committee and that: (1) relates to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective or complex judgments. The communication of a critical audit matter 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 matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

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

As described in Notes 1 and 4 to the financial statements, the Company’s allowance for credit losses totaled $83.4 million, which consists of a reserve on loans collectively evaluated for impairment (a/k/a general reserve) of $81.6 million and a reserve on loans individually evaluated (a/k/a specific reserve) of $1.8 million at December 31, 2024. The allowance for credit losses is measured on a collective loan pool 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 on collectively evaluated loans 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 the Company 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.

We identified the adjustments to historical loss factors component of the allowance for credit losses as a critical audit matter, as auditing the underlying adjustments required significant auditor judgment as amounts determined by management rely on analysis that is highly subjective and includes significant estimation uncertainty.

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

•We obtained an understanding of the relevant controls related to the adjustments to historical factors 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 adjustments to historical loss factors including testing the supporting data for agreement to internal or external source data.

•We tested management’s conclusions regarding the appropriateness of the adjustments, including magnitude and directional consistency, to historical loss factors included in the allowance for credit losses calculation.

/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.

Champaign, Illinois

February 27, 2025

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