UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(RULE 14a-101)

INFORMATION REQUIRED IN PROXY STATEMENT

SCHEDULE 14A INFORMATION

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Securities Exchange Act of 1934

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FIRST BUSEY CORPORATION

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement if other than the Registrant)

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FIRST BUSEY CORPORATION 100 WEST UNIVERSITY AVENUE CHAMPAIGN, IL 61820 V35746-P04626 Your Vote Counts! FIRST BUSEY CORPORATION 2024 Ann ual Meeting Vote by May 21, 2024 11 : 59 PM ET for shares held directly. Vote by May 19, 2024 11 :59 PM ET for shares held in the First Busey Corporation Profit Sharing Plan and Trust and in the Employee Stock Purchase Plan . You invested in FIRST BUSEY CORPORATION and it's time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy materials for the stockholder meeting to be held on May 22, 2024. Get informed before you vote View the Notice and Proxy Statement, Annual Report and Form 10-K/A on line OR you can receive a free paper or email copy of the material(s) by requesting on or before May 8, 2024. If you would like to request a copy of the material(s) fo r this and/or f uture stockholder meetings, you may (1) visit www.ProxyVote.com, (2) ca ll 1-800-579-1639 or (3) send an email to sendmaterial@proxyvote.com . If send ing an ema il , please include your control number (ind icated below) in the subject line. Unless requested, you w il l not otherwise receive a paper or ema il copy. Smartphone users Point your camera here and vote w ithout entering a ~ lnumber Vote Virtually at the Meeting* May 22, 2024 10:30 AM CDT Virtually at: www.virtualshareholdermeeting.com/BUSE2024 *We encourage you to review the meeting materials for any special requ irements for attending Fi rst Busey's Annual Meeting virtually; please note that there is no physical meeting location .

Vote at www.ProxyVote.com THIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming stockholder meeting. Please follow the instructions on the reverse side to vote on these important matters. Voting Items 1. Election of Directors Nominees: 01) Samuel P. Banks 02) George Barr 03) Stanley J. Bradshaw 04) Michael D. Cassens OS) Van A. Dukeman 06) Karen M. Jensen 07) Frederic L. Kenney 08) Stephen V. King 09) Gregory B. Lykins 1 O) Cassandra R. Sanford Board Recommends 0For 2. To approve, in a non-binding, advisory vote, the compensation of our named executive officers, as described in the O For accompanying proxy statement, which is referred to as a " say-on-pay" proposal. 3. To approve, in a non-binding, advisory vote, the frequency with which stockholders wil l vote on future say-on-pay O Year proposals. 4. To ratify the appointment of RSM US LLP as the Company's independent registered public accounting firm for the year O For ending December 31, 2024. NOTE: The proxy wi ll be voted in the discretion of the named proxies upon such other business as may properly come before the meeting or any adjournment thereof. Prefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click "Delivery Settings." V35747-P04626