FCFP First Community Financial Partners, Inc.

Notice of Special Meeting of Stockholders

TO FIRST COMMUNITY STOCKHOLDERS:

        NOTICE IS HEREBY GIVEN that First Community Financial Partners, Inc. (which we refer to as "First Community") will hold a special meeting of stockholders on June 7, 2017 at 10:30 a.m., local time, at Chicago Marriott Southwest at Burr Ridge, 1200 Burr Ridge Parkway, Burr Ridge, Illinois 60527. The purpose of the meeting is to consider and vote on the following matters:

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a proposal to approve the Agreement and Plan of Merger, dated as of February 6, 2017, between First Busey and First Community, pursuant to which First Community will merge with and into First Busey, and the transactions contemplated therein. A copy of the merger agreement is included as Appendix A to the proxy statement/prospectus accompanying this notice; and



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a proposal to the approve the adjournment of the special meeting to permit further solicitation in the event that an insufficient number of votes are cast to approve the merger agreement and the transactions contemplated therein.

        Holders of record of First Community common stock at the close of business on April 17, 2017 are entitled to receive this notice and to vote at the special meeting and any adjournments or postponements thereof. Approval of the merger agreement and the transactions contemplated therein requires the affirmative vote of the holders of a majority of the outstanding shares of First Community common stock entitled to vote. Approval of the proposal to adjourn the special meeting requires the affirmative vote of the holders of a majority of shares of First Community common stock represented in person or by proxy at the special meeting and entitled to vote.

         The board of directors of First Community unanimously recommends that you vote "FOR" approval of the merger agreement and the transactions contemplated therein and "FOR" approval to adjourn the special meeting to permit further solicitation in the event that an insufficient number of votes are cast to approve the merger agreement and the transactions contemplated therein.

        Your vote is important. Whether or not you plan to attend the meeting, please act promptly to vote your shares. You may vote your shares by telephone or over the Internet or by completing, signing and dating a proxy card and returning it in the accompanying postage paid envelope. Please review the instructions for each of your voting options described in this proxy statement/prospectus. If you attend the meeting, you may vote your shares in person, even if you have previously submitted a proxy in writing, by telephone or through the Internet. Submitting a proxy will ensure that your shares are represented at the meeting.

        We will send you a letter of transmittal separately on a later date with instructions informing you how to send in your stock certificates to the exchange agent. Please do not send in your stock certificates at this time.

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        Under Illinois law, if the merger is completed, First Community stockholders of record who do not vote to approve the merger agreement, and otherwise comply with the applicable provisions of Illinois law pertaining to objecting stockholders, will be entitled to exercise dissenters' rights and obtain payment in cash for the fair value of their shares of First Community common stock by following the procedures set forth in detail in this proxy statement/prospectus. A copy of the section of the Illinois Business Corporation Act of 1983, as amended, pertaining to dissenters' rights is included as Appendix B to this proxy statement/prospectus.

        If you have any questions regarding the accompanying proxy statement/prospectus, you may contact Glen Stiteley, First Community's Chief Financial Officer and Corporate Secretary, at (815) 725-1885 or gstiteley@fcbankgroup.com.

		By Order of the Board of Directors
		Glen L. Stiteley Corporate Secretary

Joliet, Illinois
April 25, 2017

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REFERENCES TO ADDITIONAL INFORMATION

        This proxy statement/prospectus incorporates important business and financial information about First Busey and First Community from documents filed with the SEC that are not included in or delivered with this proxy statement/prospectus. For a listing of the documents incorporated by reference into this proxy statement/prospectus, see "Where You Can Find More Information." You can obtain any of the documents filed with or furnished to the SEC by First Busey and/or First Community at no cost from the SEC's website at http://www.sec.gov. You may also request copies of these documents, including documents incorporated by reference in this proxy statement/prospectus, at no cost by contacting the appropriate company:

        The section of this proxy statement/prospectus entitled "Where You Can Find More Information" has additional information about obtaining copies of documents that First Busey and First Community has filed with the SEC.

         You will not be charged for any of these documents that you request. To obtain timely delivery of these documents, you must request them no later than five business days before the date of the special meeting. This means that stockholders requesting documents must do so by May 31, 2017, in order to receive them before the First Community special meeting.

ABOUT THIS PROXY STATEMENT/PROSPECTUS

        This document, which forms part of a registration statement on Form S-4 filed with the SEC by First Busey (File No. 333-216710), constitutes a prospectus of First Busey under Section 5 of the Securities Act of 1933, as amended, which we refer to as the "Securities Act," with respect to the shares of common stock, par value $0.001 per share, of First Busey, which we refer to as "First Busey common stock," to be issued pursuant to the Agreement and Plan of Merger, dated as of February 6, 2017, by and between First Busey and First Community, as it may be amended from time to time, which we refer to as the "merger agreement." This document also constitutes a proxy statement of First Community under Section 14(a) of the Securities Exchange Act of 1934, as amended, which we refer to as the "Exchange Act." It also constitutes a notice of meeting with respect to the special meeting at which First Community stockholders will be asked to consider and vote upon the approval of the merger agreement.

        First Busey has supplied all information contained or incorporated by reference into this proxy statement/prospectus relating to First Busey, and First Community has supplied all information contained or incorporated by reference into this proxy statement/prospectus relating to First Community.

        You should rely only on the information contained in, or incorporated by reference into, this document. No one has been authorized to provide you with information that is different from that contained in, or incorporated by reference into, this document. This document is dated April 25, 2017, and you should assume that the information in this document is accurate only as of such date. You should assume that the information incorporated by reference into this document is accurate as of the date of such document. Neither the mailing of this document to First Community stockholders nor the issuance by First Busey of shares of First Busey common stock in connection with the merger will create any implication to the contrary.

         This document does not constitute an offer to sell, or a solicitation of an offer to buy, any securities, or the solicitation of a proxy, in any jurisdiction to or from any person to whom it is unlawful to make any such offer or solicitation in such jurisdiction.

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QUESTIONS AND ANSWERS ABOUT THE MERGER

        The following questions and answers are intended to briefly address some commonly asked questions regarding the merger, the merger agreement and the special meeting. We urge you to read carefully the remainder of this proxy statement/prospectus because the information in this section may not provide all the information that might be important to you in determining how to vote. Additional important information is also contained in the appendices to, and the documents incorporated by reference in, this document. See "Where You Can Find More Information."

Q:

What is the proposed transaction?

A:

You are being asked to vote on the approval of a merger agreement that provides for the merger of First Community Financial Partners, Inc. (which we refer to as "First Community") with and into First Busey Corporation (which we refer to as "First Busey), with First Busey as the surviving company (which we refer to as the "merger proposal"). The merger is anticipated to be completed in mid-2017. At a date following the completion of the merger, First Busey intends to merge First Community Financial Bank, First Community's wholly-owned bank subsidiary, with and into Busey Bank, First Busey's wholly-owned bank subsidiary, with Busey Bank as the surviving bank (which we refer to as the "bank merger"). At such time, First Community Financial Bank's banking offices will become banking offices of Busey Bank. Until the banks are merged, First Busey will own and operate First Community Financial Bank and Busey Bank as separate bank subsidiaries.

Q:

What will First Community stockholders be entitled to receive in the merger?

A:

If the merger is completed, each share of First Community common stock issued and outstanding immediately prior to the effective time of the merger (other than shares owned by First Community as treasury stock or otherwise owned by First Community or First Busey and any dissenting shares), will be converted into the right to receive $1.35 in cash and 0.396 shares of First Busey common shares (which we refer to as the "exchange ratio") pursuant to the terms of the merger agreement, subject to certain adjustments as described in this proxy statement/prospectus. Only whole shares of First Busey common stock will be issued in the merger. As a result, cash will be paid instead of any fractional shares based on the reference price of First Busey common stock as more fully described on page 69. Shares of First Community common stock held by First Community stockholders who elect to exercise their dissenters' rights will not be converted into merger consideration.

Q:

What is the value of the per share merger consideration?

A:

The value of the merger consideration to be received by First Community stockholders will fluctuate as the market price of First Busey common stock fluctuates before the completion of the merger. This price will not be known at the time of the First Community special meeting and may be more or less than the current price of common stock or the price of First Busey common stock at the time of the special meeting.

Based on the five-day weighted average closing price of First Busey common stock as reported on the NASDAQ Global Select Market of $29.31 as of February 3, 2017, the trading day immediately preceding the public announcement date of the merger, the implied merger consideration that a First Community stockholder would be entitled to receive for each share of First Community common stock owned would be $12.95 with an aggregate transaction value of approximately $235.8 million. Based on the five-day weighted average closing price of First Busey common stock as reported on the NASDAQ Global Select Market of $28.37 as of April 17, 2017, the latest practicable date before the date of this proxy statement/prospectus, the implied merger consideration that a First Community stockholder would be entitled to receive for each share of

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First Community common stock owned would be $12.58 with an aggregate transaction value of approximately $232.0 million.

We urge you to obtain current market quotations for shares of First Busey common stock and First Community common stock.

Q:

Is the merger consideration subject to adjustment?

A:

Yes. First Community is entitled to terminate the merger agreement if the weighted average daily closing sales price (which we refer to as the "First Busey Market Value") of a share of First Busey common stock as reported on the NASDAQ Global Select Market for the five consecutive trading days prior to the first date on which all regulatory approvals (and waivers, if applicable) required for completion of the merger are received (disregarding any waiting periods) (which we refer to as the "Determination Date") is less than $22.71 per share, unless First Busey elects to increase the exchange ratio to equal the quotient obtained by dividing $8.99 by the First Busey Market Value. If First Busey elects to increase the exchange ratio, the merger agreement will remain in effect in accordance with its terms, except the stock consideration will be increased to reflect the revised exchange ratio. If First Busey declines to increase the exchange ratio, First Community will have the option to accept the original exchange ratio without adjustment. If the First Busey Market Value on the Determination Date is more than $35.90, then the exchange ratio shall be decreased to equal the quotient obtained by dividing $14.22 by the First Busey Market Value. If an adjustment to the exchange ratio would require First Busey to issue more than 19.9% of the issued and outstanding shares of into First Busey common stock at the effective time, then First Busey shall have the right to adjust the exchange ratio so that First Busey would only be required to issue no more than 19.9% of the First Busey common stock, and First Busey shall increase the cash consideration to reflect, on a per share basis, the aggregate value of the total number of shares that otherwise would have been issuable, valued at the First Busey Market Value.

Q:

Why do First Community and First Busey want to engage in the merger?

A:

First Community believes that the merger will provide First Community stockholders with substantial benefits, and First Busey believes that the merger will further its strategic growth plans. To review the reasons for the merger in more detail, see "The Merger—First Community's reasons for the merger and recommendation of the board of directors" and "The Merger—First Busey's reasons for the merger."

Q:

In addition to approving the merger agreement, what else are First Community stockholders being asked to vote on?

A:

In addition to the merger agreement and the transactions contemplated therein, First Community is soliciting proxies from holders of its common stock with respect to a proposal to adjourn the First Community special meeting to permit further solicitation in the event that an insufficient number of votes are cast to approve the merger agreement and the transactions contemplated therein (which we refer to as the "adjournment proposal"). Completion of the merger is not conditioned upon approval of the adjournment proposal.

Q:

What does the First Community board of directors recommend?

A:

First Community's board of directors has determined that the merger agreement and the transactions contemplated therein are in the best interests of First Community and its stockholders. First Community's board of directors unanimously recommends that you vote " FOR " the approval of the merger agreement and the transactions contemplated therein and " FOR " the approval to adjourn the special meeting to permit further solicitation in the event that an

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insufficient number of votes are cast to approve the merger agreement and the transactions contemplated therein. To review the reasons for the merger in more detail, see "The Merger—First Community's reasons for the merger and recommendation of the board of directors."

Q:

What vote is required to approve each proposal at the First Community special meeting, and how will abstentions and broker non-votes affect the vote?

A:

Approval of the merger agreement and the transactions contemplated therein requires the affirmative vote of the holders of a majority of the outstanding shares of First Community common stock entitled to vote. Abstentions, shares not voted and broker non-votes will have the same effect as a vote against the merger proposal. Approval of the adjournment proposal requires the affirmative vote of the holders of a majority of shares of First Community common stock represented in person or by proxy at the special meeting and entitled to vote. Abstentions are deemed to be represented at the special meeting and thereby have the same effect as a vote against the adjournment proposal. Shares not voted and broker non-votes will have no effect on the adjournment proposal, although they may prevent First Community from obtaining a quorum and require First Community to adjourn the special meeting to solicit additional proxies.

Q:

Why is my vote important?

A:

The merger cannot be completed unless the merger agreement is approved by First Community stockholders. If you fail to submit a proxy or vote in person at the special meeting, or vote to abstain, or you do not provide your broker, bank other fiduciary with voting instructions, as applicable, this will have the same effect as a vote against the approval of the merger agreement. The First Community board of directors unanimously recommends that First Community's stockholders vote " FOR " the merger proposal. Completion of the merger is not conditional upon approval of the adjournment proposal.

Q:

What do I need to do now? How do I vote?

A:

If you are a First Community stockholder, you may vote at the special meeting if you own shares of First Community common stock of record at the close of business on the record date for the special meeting, April 17, 2017. After you have carefully read and considered the information contained in this proxy statement/prospectus, please vote by a method described on your proxy card. This will enable your shares to be represented at the special meeting. You may also vote in person at the special meeting. If you do not vote by proxy and do not vote at the special meeting, this will make it more difficult to achieve a quorum for the meeting.

Q:

If my shares of common stock are held in "street name" by my broker, bank or other fiduciary, will my bank, broker or other fiduciary automatically vote my shares for me?

A:

No. Your bank, broker or other fiduciary cannot vote your shares without instructions from you. If your shares are held in "street name" through a broker, bank or other fiduciary, you must provide the record holder of your shares with instructions on how to vote the shares. Please follow the voting instructions provided by the broker, bank or other fiduciary. You may not vote shares held in street name by returning a proxy card directly to First Community, or by voting in person at the First Community special meeting, unless you provide a "legal proxy," which you must obtain from your broker, bank or other fiduciary. Further, brokers, banks or other fiduciaries who hold shares of First Community common stock on behalf of their customers may not give a proxy to First Community to vote those shares with respect to any of the proposals without specific instructions from their customers, as brokers, banks and other fiduciaries do not have discretionary voting power on these matters. Failure to instruct your broker, bank other fiduciary how to vote will have the same effect as a vote against adoption of the merger agreement.

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Q:

How will my proxy be voted?

A:

If you complete, sign, date and mail your proxy form, your proxy will be voted in accordance with your instructions. If you sign, date and send in your proxy form, but you do not indicate how you want to vote, your proxy will be voted " FOR" approval of the merger agreement and the other proposals in the notice.

Q:

Can I revoke my proxy and change my vote?

A:

You may change your vote or revoke your proxy prior to the special meeting by filing with the corporate secretary of First Community, a duly executed revocation of proxy or submitting a new proxy with a later date. You may also revoke a prior proxy by voting in person at the applicable special meeting.

Q:

Are there risks I should consider in deciding to vote on the approval of the merger agreement?

A:

Yes, in evaluating the merger agreement and the transactions contemplated therein, you should read this proxy statement/prospectus carefully, including the factors discussed in the section titled "Risk Factors" beginning on page 26.

Q:

What if I oppose the merger? Do I have dissenters' rights?

A:

First Community stockholders who do not vote in favor of approval of the merger agreement and otherwise comply with all of the procedures of the Illinois Business Corporation Law of 1980, as amend (which we refer to as the "IBCA"), will be entitled to receive payment in cash of the fair value of their shares of First Community common stock as ultimately determined under the statutory process. A copy of the applicable sections of the IBCA is attached as Appendix B to this document. This "fair value" could be more than the merger consideration but could also be less.

Q:

What are the tax consequences of the merger to me?

Each of Barack Ferrazzano Kirschbaum & Nagelberg LLP (which we refer to as "Barack Ferrazzano") and Howard & Howard Attorneys PLLC (which we refer to as "Howard & Howard") have delivered opinions, dated March 15, 2017, to the effect that the merger qualifies as a "reorganization" pursuant to Section 368(a) of the Internal Revenue Code of 1986, as amended (which we refer to as the "Internal Revenue Code"). In addition, the completion of the merger is conditioned on receipt of a tax opinion from each of Barack Ferrazzano and Howard & Howard, dated as of the closing date, to the same effect as the opinions in the preceding sentence. The opinion will not bind the Internal Revenue Service, which could take a different view. Neither First Busey nor First Community has requested or received a ruling from the Internal Revenue Service that the merger will qualify as a reorganization. Provided the merger qualifies as a reorganization for United States federal income tax purposes, First Community stockholders may recognize gain, but will not recognize loss, upon the exchange of their First Community common stock for shares of First Busey common stock and cash. If the sum of the fair market value of the First Busey common stock and the amount of cash you receive in exchange for your shares of First Community common stock exceeds the adjusted basis of your shares of First Community common stock, you will recognize taxable gain equal to the lesser of the amount of such excess or the amount of cash you receive in the exchange. Generally, any gain recognized upon the exchange will be capital gain, and any such capital gain will be long-term capital gain if you have established a holding period of more than one year for your shares of First Community common stock. Depending on certain facts specific to you, any gain could instead be characterized as ordinary dividend income. You should consult with your tax adviser for the specific tax consequences of the merger to you. See "The Merger—Material U.S. federal income tax consequences of the merger."

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Q:

When and where is First Community special meeting?

A:

The First Community special meeting will take place on June 7, 2017, at 10:30 a.m. local time, at Chicago Marriott Southwest at Burr Ridge, 1200 Burr Ridge Parkway, Burr Ridge, Illinois 60527.

Q:

Who may attend the First Community special meeting?

A:

Only First Community stockholders on the record date may attend the special meeting. If you are a stockholder of record, you will need to present the proxy card that you received or another proof of identification in order to be admitted into the meeting.

Q:

Should I send in my First Community stock certificates now?

A:

No. Either at the time of closing or shortly after the merger is completed, the exchange agent for the merger, Computershare Trust Company, N.A., will send you a letter of transmittal with instructions informing you how to send in your stock certificates to the exchange agent. You should use the letter of transmittal to exchange your First Community stock certificates for the merger consideration. Do not send in your stock certificates with your proxy form.

Q:

Whom may I contact if I cannot locate my First Community stock certificate(s)?

A:

If you are unable to locate your original First Community stock certificate(s), you should contact American Stock Transfer & Trust Company, LLC, First Community's transfer agent, at 1 (888) 509-4619, option 1, or First Community Financial Partners, Inc., Lynne M. Brooks, Shareholder Services, at (630) 789-4441.

Q:

What should I do if I hold my shares of First Community common stock in book-entry form?

A:

You are not required to take any special additional actions if your shares of First Community common stock are held in book-entry form. After the completion of the merger, shares of First Community common stock held in book-entry form automatically will be exchanged for the merger consideration, plus cash in lieu of any fractional shares.

Q:

What should I do if I receive more than one set of voting materials?

A:

First Community stockholders may receive more than one set of voting materials, including multiple copies of this proxy statement/prospectus and multiple proxy cards or voting instruction cards. For example, if you hold shares of First Community common stock in more than one brokerage account, you will receive a separate voting instruction card for each brokerage account in which you hold such shares. If you are a holder of record of First Community common stock and your shares are registered in more than one name, you will receive more than one proxy card. Please complete, sign, date and return each proxy card and voting instruction card that you receive or otherwise follow the voting instructions set forth in this proxy statement/prospectus to ensure that you vote every share of First Community common stock that you own.

Q:

When is the merger expected to be completed?

A:

We will try to complete the merger as soon as reasonably possible. Before that happens, the merger agreement must be approved by stockholders of First Community, and we must obtain the necessary regulatory approvals. Assuming First Community stockholders vote to approve the merger and adopt the merger agreement and we obtain the other necessary approvals and satisfaction or waiver of the other conditions to the closing described in the merger agreement, we expect to complete the merger in mid-2017. See "Description of the Merger Agreement—Conditions to completion of the merger."

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Q:

Is completion of the merger subject to any conditions besides stockholder approval?

A:

Yes. The transaction must receive the required regulatory approvals, and there are other standard closing conditions that must be satisfied. See "Description of the Merger Agreement—Conditions to completion of the merger."

Q:

What happens if the merger is not completed?

A:

First Community and First Busey expect to complete the merger in mid-2017. However, neither First Community nor First Busey can assure you of when or if the merger will be completed. First Community and First Busey must first obtain the approval of First Community stockholders for the merger, as well as obtain necessary regulatory approvals and satisfy certain other standard closing conditions. If the merger is not completed, First Community stockholders will not receive any consideration for their shares and will continue to be First Community stockholders. Each of First Busey and First Community will remain independent companies. Under certain circumstances, First Busey and First Community may be required to pay the other party a fee with respect to the termination of the merger agreement, as described under "Description of the Merger Agreement—Termination fees."

Q:

Who can answer my other questions?

A:

If you have more questions about the merger or how to submit your proxy, or if you need additional copies of this proxy statement/prospectus or the enclosed proxy form, you should contact: First Community Financial Partners, Inc., Glen Stiteley, Corporate Secretary, 2801 Black Road, Joliet, Illinois 60435, (815) 725-1885.

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RISK FACTORS

         In addition to general investment risks and the other information contained in or incorporated by reference into this proxy statement/prospectus, including the matters addressed under the section "Special Notes Concerning Forward-Looking Statements," you should carefully consider the following risk factors in deciding how to vote for the proposals presented in this proxy statement/prospectus. You should also consider the other information in this proxy statement/prospectus and the other documents incorporated by reference into this proxy statement/prospectus. See "References to Additional Information" in the forepart of this proxy statement/prospectus and the section of this proxy statement/prospectus entitled "Where You Can Find More Information."

Because the Market Price of First Busey Common Shares Will Fluctuate, First Community Stockholders Cannot Be Sure of the Value of the Merger Consideration They Will Receive.

        Upon completion of the merger, each share of First Community common stock will be converted into the right to receive $1.35 in cash and 0.396 shares of First Busey common stock pursuant to the terms of the merger agreement, subject to certain adjustments as described in this proxy statement/prospectus. The market value of the merger consideration may vary from the closing price of First Busey common stock on the date the merger was announced, on the date that this document was mailed to First Community stockholders, on the date of the special meeting of the First Community stockholders and on the date the merger is completed and thereafter. Any change in the exchange ratio or the market price of First Busey common stock prior to completion of the merger will affect the amount of and the market value of the merger consideration that First Community stockholders will receive upon completion of the merger. Accordingly, at the time of the special meeting, First Community stockholders will not know or be able to calculate with certainty the amount or the market value of the merger consideration they would receive upon completion of the merger. Stock price changes may result from a variety of factors, including general market and economic conditions, changes in business, operations and prospects, and regulatory considerations. Many of these factors are beyond First Busey's or First Community's control. You should obtain current market quotations for shares of First Busey common stock and for shares of First Community common stock before you vote and before you make your election.

The Market Price of First Busey Common Stock after the Merger May be Affected by Factors Different from Those Affecting the Shares of First Community or First Busey Currently.

        Upon completion of the merger, holders of First Community common stock will become holders of First Busey common stock. First Busey's business differs in important respects from that of First Community and they currently operate in different markets. Accordingly, the results of operations of the combined company and the market price of First Busey common stock after the completion of the merger may be affected by factors different from those currently affecting the independent results of operations of each of First Busey and First Community. For a discussion of the businesses and markets of First Busey and First Community and of some important factors to consider in connection with those businesses, please see the documents incorporated by reference in this proxy statement/prospectus and referred to under "Where You Can Find More Information."

First Community Stockholders Will Have a Reduced Ownership and Voting Interest After the Merger and Will Exercise Less Influence Over Management.

        First Community stockholders currently have the right to vote in the election of the First Community board of directors and on other matters requiring stockholder approval under Illinois law and First Community's articles of incorporation and bylaws. Upon the completion of the merger, each First Community stockholder will become a stockholder of First Busey with a percentage ownership of First Busey that is smaller than such stockholder's percentage ownership of First Community.

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Additionally, only one member of the First Busey board of directors after the completion of the merger will be designated by First Community upon the completion of the merger. Based on the number of issued and outstanding First Busey common shares and shares of First Community common stock on April 17, 2017, and based on the exchange ratio of 0.396, stockholders of First Community, as a group, will receive shares in the merger constituting approximately 15.5% of First Busey common shares expected to be outstanding immediately after the merger (without giving effect to any First Busey common shares held by First Community stockholders prior to the merger). In addition, on March 13, 2017, First Busey announced that it entered into an Agreement and Plan of Merger to acquire Mid Illinois. As part of the merger consideration for that transaction, First Busey will issue shares of its common stock to Mid Illinois's stockholders such that, in the aggregate, 70% of the outstanding shares of Mid Illinois will be converted into the right to receive shares of First Busey common stock and the remaining 30% of the outstanding shares will be converted into the right to receive cash. See "Recent Developments." The issuance of First Busey shares in the Mid Illinois transaction will be further dilutive to First Community stockholders. Because of this, current First Community stockholders, as a group, will have less influence on the board of directors, management and policies of First Busey (as the combined company following the merger) than they now have on the board of directors, management and policies of First Community.

First Busey May Fail to Realize the Anticipated Benefits of the Merger.

        First Busey and First Community have operated and, until the completion of the merger, will continue to operate, independently. The success of the merger, including anticipated benefits and cost savings, will depend on, among other things, First Busey's ability to combine the businesses of First Busey and First Community in a manner that permits growth opportunities, including, among other things, enhanced revenues and revenue synergies, an expanded market reach and operating efficiencies, and does not materially disrupt the existing customer relationships of First Busey or First Community nor result in decreased revenues due to any loss of customers. If First Busey is not able to successfully achieve these objectives, the anticipated benefits of the merger may not be realized fully or at all or may take longer to realize than expected. Failure to achieve these anticipated benefits could result in increased costs, decreases in the amount of expected revenues and diversion of management's time and energy and could have an adverse effect on the surviving corporation's business, financial condition, operating results and prospects.

        Certain employees may not be employed by First Busey after the merger. In addition, employees that First Busey wishes to retain may elect to terminate their employment as a result of the merger, which could delay or disrupt the integration process. It is possible that the integration process could result in the disruption of First Busey's or First Community's ongoing businesses or cause inconsistencies in standards, controls, procedures and policies that adversely affect the ability of First Busey or First Community to maintain relationships with customers and employees or to achieve the anticipated benefits and cost savings of the merger.

        Among the factors considered by the Boards of Directors of First Busey and First Community in connection with their respective approvals of the merger agreement were the benefits that could result from the merger. There can be no assurance that these benefits will be realized within the time periods contemplated or at all.

Regulatory Approvals May Not Be Received, May Take Longer than Expected or May Impose Conditions that Are Not Presently Anticipated or Cannot Be Met.

        Before the transactions contemplated in the merger agreement can be completed, various approvals must be obtained from the bank regulatory and other governmental authorities. In deciding whether to grant regulatory clearances, the relevant governmental entities will consider a variety of factors, including the regulatory standing of each of the parties. An adverse development in either

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party's regulatory standing or other factors could result in an inability to obtain one or more of the required regulatory approvals or delay their receipt. The terms and conditions of the approvals that are granted may impose requirements, limitations or costs or place restrictions on the conduct of the combined company's business. First Busey and First Community believe that the merger should not raise significant regulatory concerns and that First Busey will be able to obtain all requisite regulatory approvals in a timely manner. Despite the parties' commitments to use their reasonable best efforts to comply with conditions imposed by regulatory entities, under the terms of the merger agreement, First Busey and First Community will not be required to complete the merger if any such approvals would reasonably be expected to materially restrict or burden First Busey following the merger. There can be no assurance that regulators will not impose conditions, terms, obligations or restrictions and that such conditions, terms, obligations or restrictions will not have the effect of delaying the completion of the merger, imposing additional material costs on or materially limiting the revenues of the combined company following the merger or otherwise reduce the anticipated benefits of the merger if the merger were completed successfully within the expected timeframe. In addition, neither First Busey nor First Community can provide assurance that any such conditions, terms, obligations or restrictions will not result in the delay or abandonment of the merger. Additionally, the completion of the merger is conditioned on the absence of certain orders, injunctions or decrees by any court or regulatory agency of competent jurisdiction that would prohibit or make illegal the completion of the merger.

The Merger Agreement May Be Terminated in Accordance with Its Terms and the Merger May Not Be Completed.

        The merger agreement is subject to a number of conditions which must be fulfilled in order to complete the merger. Those conditions include: approval of the merger agreement and the transactions it contemplates by First Community stockholders, receipt of certain requisite regulatory approvals, absence of orders prohibiting completion of the merger, effectiveness of the registration statement of which this proxy statement/prospectus is a part, approval of the issuance of First Busey common stock, as applicable, for listing on the NASDAQ Global Select Market, the accuracy of the representations and warranties by both parties (subject to the materiality standards set forth in the merger agreement) and the performance by both parties of their covenants and agreements, and the receipt by both parties of legal opinions from their respective tax counsels. These conditions to the closing of the merger may not be fulfilled in a timely manner or at all, and, accordingly, the merger may not be completed. In addition, the parties can mutually decide to terminate the merger agreement at any time, before or after stockholder approval, or First Busey or First Community may elect to terminate the merger agreement in certain other circumstances.

Termination of the Merger Agreement Could Negatively Impact First Community.

        If the merger is not completed for any reason, including as a result of First Community stockholders declining to approve the merger agreement, the ongoing business of First Community may be adversely impacted and, without realizing any of the anticipated benefits of completing the merger, First Community would be subject to a number of risks, including the following:

•

First Community may experience negative reactions from the financial markets, including negative impacts on its stock price (including to the extent that the current market price reflects a market assumption that the merger will be completed);



•

First Community may experience negative reactions from its customers, vendors and employees;



•

First Community will have incurred substantial expenses and will be required to pay certain costs relating to the merger, whether or not the merger is completed;



•

the merger agreement places certain restrictions on the conduct of First Community's businesses prior to completion of the merger. Such restrictions, the waiver of which is subject to the

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consent of First Busey (not to be unreasonably withheld, conditioned or delayed), may prevent First Community from making certain acquisitions or taking certain other specified actions during the pendency of the merger; and

•

matters relating to the merger (including integration planning) will require substantial commitments of time and resources by First Community management, which would otherwise have been devoted to other opportunities that may have been beneficial to First Community as an independent company.

        If the merger agreement is terminated and First Community's board of directors seeks another merger or business combination, First Community stockholders cannot be certain that First Community will be able to find a party willing to offer equivalent or more attractive consideration than the consideration First Busey has agreed to provide in the merger, or that such other merger or business combination will be completed. If the merger agreement is terminated under certain circumstances, First Community may be required to pay a termination fee of $9.0 million to First Busey.

First Community Will Be Subject to Business Uncertainties and Contractual Restrictions While the Merger Is Pending.

        Uncertainty about the effect of the merger on employees and customers may have an adverse effect on First Community and, consequently, on First Busey. These uncertainties may impair First Community's ability to attract, retain and motivate key personnel until the merger is completed, and could cause customers and others that deal with First Community to seek to change existing business relationships with First Community. Retention of certain employees may be challenging during the pendency of the merger, as certain employees may experience uncertainty about their future roles. If key employees depart because of issues relating to the uncertainty and difficulty of integration or a desire not to remain with the business, First Busey's business following the merger could be negatively impacted. In addition, the merger agreement restricts First Community from making certain transactions and taking other specified actions without the consent of First Busey until the merger occurs. These restrictions may prevent First Community from pursuing attractive business opportunities that may arise prior to the completion of the merger.

First Community Directors and Officers May Have Interests in the Merger Different From the Interests of First Community Stockholders.

        The interests of some of the directors and executive officers of First Community may be different from those of First Community stockholders, and directors and officers of First Community may be participants in arrangements that are different from, or are in addition to, those of First Community stockholders. The members of the First Community's board of directors knew about these additional interests and considered them among other matters, when making its decision to approve the merger agreement, and in recommending that First Community's common stockholders vote in favor of adopting the merger agreement. Such interests include, among others:

•

The acceleration of vesting of outstanding director stock options, restricted stock units and performance stock units;



•

Entering into an employment agreement with the Chief Executive Officer of First Community;



•

The receipt of certain change in control benefits; and



•

The continuation of service on First Busey's board of directors of one First Community director.

        These interests are more fully described in this proxy statement/prospectus under the section titled "The Merger—Interests of certain persons in the merger."

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The Merger Agreement Contains Provisions that May Discourage Other Companies from Trying to Acquire First Community for Greater Merger Consideration.

        The merger agreement contains provisions that may discourage a third party from submitting a business combination proposal to First Community that might result in greater value to First Community's stockholders than the proposed merger with First Busey or may result in a potential competing acquirer proposing to pay a lower per share price to acquire First Community than it might otherwise have proposed to pay absent such provisions. These provisions include a general prohibition on First Community from soliciting, or, subject to certain exceptions relating to the exercise of fiduciary duties by First Community's board of directors, entering into discussions with any third party regarding any acquisition proposal or offers for competing transactions. First Community also has an unqualified obligation to submit the proposal to approve the merger to a vote by its stockholders, even if First Community receives an alternative acquisition proposal that its board of directors believes is superior to the merger, unless the merger agreement has been terminated in accordance with its terms. In addition, First Community may be required to pay First Busey a termination fee of $9.0 million upon termination of the merger agreement in certain circumstances involving acquisition proposals for competing transactions. See "Description of the Merger Agreement—Termination" and "Description of the Merger Agreement—Termination fees."

The Unaudited Pro Forma Combined Condensed Consolidated Financial Information Included in This Proxy Statement/Prospectus Is Preliminary and the Actual Financial Condition and Results of Operations After the Merger May Differ Materially.

        The unaudited pro forma financial information included in this proxy statement/prospectus is presented for illustrative purposes only and is not necessarily indicative of what the combined company's actual financial position or results of operations would have been had the merger been completed on the date(s) indicated. The preparation of the pro forma financial information is based upon available information and certain assumptions and estimates that First Busey and First Community currently believe are reasonable. The unaudited pro forma financial information reflects adjustments, which are based upon preliminary estimates, to allocate the purchase price to First Community's net assets. The purchase price allocation reflected in this proxy statement/prospectus is preliminary, and the final allocation of the purchase price will be based upon the actual purchase price and the fair value of the assets and liabilities of First Community as of the date of the completion of the merger. In addition, following the completion of the merger, there may be further refinements of the purchase price allocation as additional information becomes available. Accordingly, the final purchase accounting adjustments may differ materially from the pro forma adjustments reflected in this proxy statement/prospectus.

The Opinion of First Community's Financial Advisor Will Not Reflect Changes in Circumstances Between the Signing of the Merger Agreement and the Completion of the Merger.

        First Community has not obtained an updated opinion from its financial advisor as of the date of this proxy statement/prospectus. Changes in the operations and prospects of First Community or First Busey, general market and economic conditions and other factors that may be beyond the control of First Community or First Busey, and on which First Community's financial advisor's opinion was based, may significantly alter the value of First Community or the prices of the First Busey common shares or shares of First Community common stock by the time the merger is completed. The opinion does not speak as of the time the merger will be completed or as of any date other than the date of such opinion. Because First Community does not currently anticipate asking its financial advisor to update its opinion, the opinion will not address the fairness of the merger consideration from a financial point of view at the time the merger is completed.

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First Busey and First Community Will Incur Transaction and Integration Costs in Connection with the Merger.

        Each of First Busey and First Community has incurred and expects that it will incur significant, non-recurring costs in connection with consummating the merger. In addition, First Busey will incur integration costs following the completion of the merger as First Busey integrates the businesses of the two companies, including facilities and systems consolidation costs and employment-related costs. There can be no assurances that the expected benefits and efficiencies related to the integration of the businesses will be realized to offset these transaction and integration costs over time. See the risk factor entitled "—First Busey May Fail to Realize the Anticipated Benefits of the Merger" on page 27. First Busey and First Community may also incur additional costs to maintain employee morale and to retain key employees. First Busey and First Community will also incur significant legal, financial advisor, accounting, banking and consulting fees, fees relating to regulatory filings and notices, SEC filing fees, printing and mailing fees and other costs associated with the merger.

The shares of First Busey common stock to be received by First Community common stockholders as a result of the merger will have different rights from the shares of First Community common stock.

        Upon completion of the merger, First Community common stockholders will become First Busey stockholders and their rights as stockholders will be governed by the Nevada Revised Statutes and the First Busey articles of incorporation and bylaws. The rights associated with First Community common stock are different from the rights associated with First Busey common stock. Please see "Comparison of Rights of First Busey Stockholders and First Community Stockholders" for a discussion of the different rights associated with First Busey common stock.

The Dodd-Frank Act, among other things, subjects banks with assets in excess of $10 billion to additional costs.

        The Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (which we refer to as the "Dodd-Frank Act") and its implementing regulations subject banks with assets in excess of $10 billion to additional requirements, such as the imposition of higher Federal Deposit Insurance Corporation (which we refer to as "FDIC") premiums, reduced debit card interchange fees, enhanced risk management frameworks and stress testing, all of which increase operating costs and reduce earnings. As First Busey approaches $10 billion in assets, it will be required to incur additional costs to address these additional requirements.

Risks Relating to First Busey's Business

        You should read and consider risk factors specific to First Busey's business that will also affect the combined company after the merger. These risks are described in the sections entitled "Risk Factors" in First Busey's Annual Report on Form 10-K for the fiscal year ended December 31, 2016, and in other documents incorporated by reference into this proxy statement/prospectus. Please see the section entitled "Where You Can Find More Information" for the location of information incorporated by reference into this proxy statement/prospectus.

Risks Relating to First Community's Business

        You should read and consider risk factors specific to First Community's business that will also affect the combined company after the merger. These risks are described in the sections entitled "Risk Factors" in First Community's Annual Report on Form 10-K for the fiscal year ended December 31, 2016, and in other documents incorporated by reference into this proxy statement/prospectus. Please see the section entitled "Where You Can Find More Information" for the location of information incorporated by reference into this proxy statement/prospectus.

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SPECIAL NOTES CONCERNING FORWARD-LOOKING STATEMENTS

        This proxy statement/prospectus contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 with respect to the financial condition, results of operations, plans, objectives, future performance and business of First Busey and First Community. Forward-looking statements, which may be based upon beliefs, expectations and assumptions of First Busey's and First Community's management and on information currently available to management, are generally identifiable by the use of words such as "believe," "expect," "anticipate," "plan," "intend," "estimate," "may," "will," "would," "could," "should" or other similar expressions. Additionally, all statements in this proxy statement/prospectus, including forward-looking statements, speak only as of the date they are made, and neither First Busey nor First Community undertakes any obligation to update any statement in light of new information or future events. A number of factors, many of which are beyond the ability of First Busey and First Community to control or predict, could cause actual results to differ materially from those in its forward-looking statements. These factors include, among others, the following:

•

the possibility that any of the anticipated benefits of the proposed transaction between First Busey and First Community will not be realized or will not be realized within the expected time period;



•

the risk that integration of operations of First Community with those of First Busey will be materially delayed or will be more costly or difficult than expected;



•

the inability to complete the proposed transaction due to the failure of the required stockholder approval;



•

the failure to satisfy other conditions to completion of the proposed transaction, including receipt of required regulatory and other approvals;



•

the failure of the proposed transaction to close for any other reason;



•

the potential impact of the announcement of the transaction on third party relationships, including customer relationships, and operating results;



•

the possibility that the transaction may be more expensive to complete than anticipated, including as a result of unexpected factors or events;



•

the strength of the local and national economy;



•

customer acceptance of the combined company's products and services;



•

changes in state and federal laws, regulations and governmental policies concerning First Busey's and First Community's general business;



•

changes in interest rates and prepayment rates of First Busey's and First Community's assets;



•

increased competition in the financial services sector and the inability to attract new customers;



•

changes in technology and the ability to develop and maintain secure and reliable electronic systems;



•

the loss of key executives or employees;



•

changes in consumer spending;



•

unexpected results of acquisitions, including the acquisition of First Community;



•

unexpected outcomes of existing or new litigation involving First Busey or First Community;



•

the economic impact of any future terrorist threats or attacks;

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•

the economic impact of exceptional weather occurrences such as tornadoes, hurricanes, floods, and blizzards; and



•

changes in accounting policies and practices.

        These risks and uncertainties should be considered in evaluating forward-looking statements and undue reliance should not be placed on such statements. Additional information concerning First Busey and First Community and their business, including additional factors that could materially affect First Busey's and First Community's financial results, are included in First Busey's and First Community's filings with the SEC.

Non-GAAP Financial Information

        This proxy statement/prospectus contains certain financial information determined by methods other than in accordance with GAAP. These non-GAAP measures are used by management, together with the related GAAP measures, in analysis of the companies' performance and in making business decisions. Management also uses these measures for peer comparisons.

        The non-GAAP disclosures contained herein should not be viewed as substitutes for the results determined to be in accordance with GAAP, nor are they necessarily comparable to non-GAAP performance measures that may be presented by other companies.

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INFORMATION ABOUT THE SPECIAL MEETING OF FIRST COMMUNITY STOCKHOLDERS

Purpose

        First Community stockholders are receiving this proxy statement/prospectus because on April 17, 2017, the record date for the special meeting of stockholders to be held on June 7, 2017, at Chicago Marriott Southwest at Burr Ridge, 1200 Burr Ridge Parkway, Burr Ridge, Illinois 60527 at 10:30 a.m., local time, they owned shares of the common stock of First Community, and the board of directors of First Community is soliciting proxies for the matters to be voted on at this special meeting, as described in more detail below. Copies of this proxy statement/prospectus began to be mailed to holders of First Community common stock on May 1, 2017, and is accompanied by a proxy card for use at the special meeting and at any adjournment(s) of the meeting.

        At the special meeting, First Community board of directors will ask you to vote upon the following:

•

a proposal to approve the merger agreement and the transactions contemplated therein; and



•

a proposal to approve an adjournment of the special meeting to permit further solicitation in the event that an insufficient number of votes are cast to approve the merger agreement and the transactions contemplated therein.

         When you sign the enclosed proxy card or otherwise vote pursuant to the instructions set forth on the proxy card, you appoint the proxy holder as your representative at the special meeting. The proxy holder will vote your shares as you have instructed in the proxy card, thereby ensuring that your shares will be voted whether or not you attend the special meeting. Even if you plan to attend the special meeting, we ask that you instruct the proxies how to vote your shares in advance of the special meeting just in case your plans change.

         If you have not already done so, please complete, date and sign the accompanying proxy card and return it promptly in the enclosed, postage paid envelope or otherwise vote pursuant to the instructions set forth on the proxy card. Instead of voting by mailing a proxy card, record stockholders can vote their shares of First Community common stock via the Internet or by telephone. The Internet and telephone voting procedures are designed to authenticate stockholders' identities, allow stockholders to provide their voting instructions and confirm that their instructions have been recorded properly. Specific instructions for Internet or telephone voting are set forth on the enclosed proxy card. If you do not vote your shares as instructed on the proxy card, or if you do not attend and cast your vote at the special meeting, the effect will be a vote against the merger agreement and the transactions contemplated therein.

Record date, quorum and vote required

        The record date for the First Community special meeting is April 17, 2017. First Community's stockholders of record as of the close of business on that day will receive notice of and will be entitled to vote at the special meeting. As of the record date, there were 17,744,886 shares of First Community common stock outstanding and entitled to vote at the special meeting. The outstanding shares are held by approximately 750 holders of record.

        The presence, in person or by proxy, of a majority of the shares of First Community common stock entitled to vote on the merger agreement is necessary to constitute a quorum at the special meeting. Each share of First Community common stock outstanding on the record date entitles its holder to one vote on the matters being brought before the special meeting.

        To determine the presence of a quorum at the special meeting, First Community will also count as present the shares of First Community common stock present in person but not voting, and the shares of common stock for which First Community has received proxies but with respect to which the holders

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