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As filed with the Securities and Exchange Commission on February 22, 2023

Registration No. 333-

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-4

REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

BYLINE BANCORP, INC.

(Exact name of registrant as specified in its charter)

Delaware

(State or other jurisdiction of
incorporation or organization)

6022

(Primary Standard Industrial
Classification Code Number)

36-3012593

(I.R.S. Employer
Identification Number)

180 North LaSalle Street, Suite 300
Chicago, Illinois 60601
(773) 244-7000

(Address, including zip code, and telephone number, including area code, of Registrant’s principal executive offices)

Alberto J. Paracchini
President
Byline Bancorp, Inc.
180 North LaSalle Street, Suite 300
Chicago, Illinois 60601
(773) 244-7000

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Daniel C. McKay, II
Jennifer Durham King
Vedder Price P.C.
222 North LaSalle Street, Suite 2600
Chicago, Illinois 60601
Phone: (312) 609-7500

Robert M. Fleetwood
Barack Ferrazzano Kirschbaum & Nagelberg LLP
200 West Madison Street, Suite 3900
Chicago, Illinois 60606
Phone: (312) 629-7329

Approximate date of commencement of proposed sale of the securities to the public: As soon as practicable after this registration statement becomes effective and upon completion of the merger.

If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box: ☐

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

	Large accelerated filer ☐			Accelerated filer ☒
	Non-accelerated filer ☐			Smaller reporting company ☐
				Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

If applicable, place an X in the box to designate the appropriate rule provision relied upon in conducting this transaction:

Exchange Act Rule 13e-4(i) (Cross-Border Issuer Tender Offer) ☐

Exchange Act Rule 14d-1(d) (Cross-Border Third-Party Tender Offer) ☐

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

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The information contained herein is subject to completion or amendment. A registration statement relating to the shares of Byline Bancorp, Inc. common stock to be issued in the merger has been filed with the Securities and Exchange Commission. These securities may not be sold, nor may offers to buy be accepted, prior to the time the registration statement becomes effective. This proxy statement/prospectus shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of these securities in any jurisdiction in which such offer, solicitation or sale is not permitted or would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction.

PRELIMINARY PROXY STATEMENT/PROSPECTUS
SUBJECT TO COMPLETION, DATED FEBRUARY 22, 2023

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Merger Proposal — Your Vote Is Important

On November 30, 2022, Byline Bancorp, Inc., which we refer to as Byline, and Inland Bancorp, Inc., which we refer to as Inland, and Butterfield Acquisition Corporation, a wholly owned subsidiary of Byline (which we refer to as “merger sub”), entered into an Agreement and Plan of Merger (which we refer to as the merger agreement), pursuant to which Byline has agreed to acquire Inland. Upon the terms and subject to the conditions of the merger agreement, merger sub will be merged with and into Inland, with Inland as the surviving corporation and wholly owned subsidiary of Byline (which we refer to as the merger). Immediately following the merger, Inland will be merged with and into Byline, with Byline as the surviving corporation (which we refer to as the parent merger), and immediately following the parent merger, Inland Bank and Trust (which we refer to as Inland Bank), an Illinois state chartered bank and wholly owned subsidiary of Inland, will merge with and into Byline Bank, an Illinois chartered bank and wholly owned subsidiary of Byline, with Byline Bank as the resulting bank as a wholly owned subsidiary of Byline (which we refer to as the bank merger).

Stockholders of Inland will receive the following for each share of Inland common stock, par value $1.00 per share (which we refer to as Inland common stock), they own (other than shares, if any, owned by Inland or Byline or any shares as to which statutory appraisal rights have been properly exercised and perfected), which we refer to as the “merger consideration”: (i) the number of shares of Byline’s common stock, par value $0.01 per share, equal to the quotient obtained by dividing (A) 6,389,351 by (B) the number of shares of Inland common stock issued and outstanding immediately prior to the effective time of the merger (which we refer to as the “effective time”) (the “Exchange Ratio”); and (ii) a cash payment in the amount equal to the quotient obtained by dividing (A) $22,867,150.20 by (B) the number of shares of Inland common stock issued and outstanding immediately prior to the effective time (the “Cash Consideration”), subject to adjustment in the event the dollar amount of Inland’s tangible common equity at closing is above or below certain thresholds set forth in the merger agreement; provided, however, that in the event Inland has less than 33,628,162 shares of common stock issued and outstanding at closing, then (1) the Exchange Ratio will be equal to 0.19 share of Byline common stock and (2) the Cash Consideration will be equal to $0.68, for each share of Inland common stock issued and outstanding at closing. Inland stock options will be cancelled and the holder thereof will be entitled to a cash payment pursuant to the terms of the merger agreement.

Byline common stock currently trades on the New York Stock Exchange, or NYSE, under the symbol “BY”. Inland common stock is privately held and not traded in any public market. The shares of Byline common stock issued pursuant to the merger will be registered under the Securities Act of 1933, as amended, and will trade on the NYSE at closing.

The value of the merger consideration will fluctuate as the market price of Byline common stock fluctuates before the completion of the merger. Thus, the value of the merger consideration will not be known at the time of the special meeting of Inland stockholders called for the purpose of voting on the merger agreement and the market price of Byline common stock at the time of completion of the merger may be more or less than the current price of Byline common stock or the price of Byline common stock at the time of the special meeting.

Based on the closing price of Byline common stock as reported on the NYSE of $22.21 as of November 29, 2022, the trading day prior to the day on which the public announcement of the merger was made, and assuming there are no adjustments pursuant to the merger agreement, the implied value of the merger consideration was approximately $4.90 per share of Inland common stock and the implied aggregate transaction value on a fully diluted basis was approximately $165.0 million.

Based on the closing price of Byline common stock as reported on the NYSE of $[•] as of [•], 2023, the last practicable date before the date of this proxy statement/prospectus, and assuming there are no adjustments pursuant to the merger agreement, the implied value of the merger consideration was approximately $[•] per share of Inland common stock and the implied aggregate transaction value on a fully diluted basis was approximately $[•] million. We urge you to obtain current market quotations for shares of Byline common stock.

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We cannot complete the merger unless we obtain the necessary approval from the stockholders of Inland as described in the attached proxy statement/prospectus. Accordingly, Inland will hold a special meeting of its stockholders in connection with the merger at 2:00 p.m., local time, on [•], [•], 2023, at 2901 Butterfield Road, Oak Brook, Illinois 60523, which we refer to as the special meeting. Inland stockholders will be asked to vote to adopt the merger agreement, which we refer to as the merger proposal, and to approve one or more adjournments of the special meeting, if necessary or appropriate, as determined by Inland, including adjournments to permit further solicitation of proxies in favor of the merger proposal, which we refer to as the adjournment proposal. Approval of the merger proposal requires the affirmative vote of holders of two-thirds of the outstanding shares of common stock of Inland. The adjournment proposal will be approved if a majority of the shares having voting power present in person or represented by proxy at the special meeting are voted in favor of the adjournment proposal.

Inland’s board of directors has unanimously approved the merger agreement, has unanimously determined that the merger agreement and the transactions contemplated thereby, including the merger, are advisable and in the best interests of Inland and its stockholders, and unanimously recommends that Inland stockholders vote “FOR” the merger proposal and “FOR” the adjournment proposal.

YOUR VOTE IS VERY IMPORTANT. We cannot complete the merger unless Inland’s stockholders approve the merger proposal.

Regardless of whether you plan to attend the special meeting, please vote as soon as possible. If you hold stock in your name as a stockholder of record of Inland, please submit a proxy to have your shares voted as promptly as possible by either: (1) dialing the telephone number shown on your proxy card and following the instructions to vote by phone; (2) logging onto the website shown on your proxy card and following the instructions to vote online; or (3) signing and returning the accompanying proxy card in the enclosed postage-paid return envelope. You may also cast your vote in person at the special meeting. If you hold your stock in “street name” through a bank or broker, please follow the instructions on the voting instruction card furnished by the record holder.

The attached proxy statement/prospectus contains a more complete description of the merger agreement and the special meeting. You should read this entire proxy statement/prospectus carefully because it contains important information about the merger. In particular, you should read the information under the section entitled “Risk Factors” beginning on page [•]. You may also obtain information about Byline from documents that it has filed with the Securities and Exchange Commission (which we refer to as the SEC).

Thank you for your cooperation and continued support.

Sincerely,

Peter Stickler
President
Inland Bancorp, Inc.

Neither the SEC nor any state securities regulatory body has approved or disapproved of the securities to be issued under this proxy statement/prospectus or determined if this proxy statement/prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The securities to be issued in the merger are not savings or deposit accounts or other obligations of any bank or nonbank subsidiary of any of the parties, and they are not insured by the Federal Deposit Insurance Corporation or any other governmental agency.

This proxy statement/prospectus is dated [•], 2023, and is first being mailed to Inland’s stockholders on or about [•], 2023.

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NOTICE OF SPECIAL MEETING OF STOCKHOLDERS TO BE HELD ON [•], 2023

Dear Fellow Stockholders of Inland Bancorp, Inc.:

Inland Bancorp, Inc., a Maryland corporation (which we refer to as Inland), will hold a special meeting of Inland stockholders, at 2:00 p.m., local time, on [•], [•], 2023, at 2901 Butterfield Road, Oak Brook, Illinois 60523 (which we refer to as the special meeting), to consider and vote on the following matters:

1. a proposal to adopt the Agreement and Plan of Merger, dated as of November 30, 2022, by and among Inland, Butterfield Acquisition Corporation (which we refer to as merger sub) and Byline Bancorp, Inc. (which we refer to as Byline), as such agreement may be amended from time to time (which we refer to as the merger agreement and a copy of which is attached to the accompanying proxy statement/prospectus as Appendix A), pursuant to which merger sub will be merged with and into Inland, with Inland as the surviving corporation and wholly owned subsidiary of Byline (which we refer to as the merger), and, immediately following the merger, Inland will be merged with and into Byline, with Byline as the surviving corporation (which, together with the merger, we refer to as the merger proposal); and

2. a proposal to adjourn the special meeting, if necessary or appropriate, as determined by Inland, to solicit additional proxies in favor of the merger proposal (which we refer to as the adjournment proposal).

We have fixed the close of business on [•], 2023, as the record date for the special meeting. Only Inland stockholders of record on that date are entitled to notice of, and to vote at, the special meeting or any adjournment or postponement of the special meeting. Approval of the merger proposal requires the affirmative vote of holders of two-thirds of the outstanding shares of Inland common stock. The adjournment proposal will be approved if a majority of the shares having voting power present in person or represented by proxy at the special meeting are voted in favor of the adjournment proposal.

Your vote is very important. We cannot complete the merger unless Inland’s stockholders approve the merger proposal. Regardless of whether you plan to attend the special meeting, please vote as soon as possible. If you hold stock in your name as a stockholder of record of Inland, please submit a proxy to have your shares voted as promptly as possible by either: (1) dialing the telephone number shown on your proxy card and following the instructions to vote by phone; (2) logging onto the website shown on your proxy card and following the instructions to vote online; or (3) signing and returning the accompanying proxy card in the enclosed postage-paid return envelope. You may also cast your vote in person at the special meeting. If you hold your stock in “street name” through a bank or broker, please follow the instructions on the voting instruction card furnished by the record holder.

Inland stockholders should not send in any stock certificate(s) with their proxy card. If the merger proposal is approved, transmittal materials with instructions for the submission of Inland stock certificates will be provided to Inland stockholders under separate cover and the stock certificates should be sent at that time.

Please note that, under Sections 3-202 and 3-203 of the Maryland General Corporation Law, as amended (which we refer to as the MGCL), a copy of which is attached as Appendix B to the accompanying proxy statement/prospectus, holders of Inland common stock who do not vote in favor of the merger

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proposal will have the right to seek appraisal of the fair value of their shares of Inland common stock as determined under the MGCL if the merger is completed, but only if they submit a written demand for such an appraisal prior to the vote on the merger proposal and comply with the other Maryland law procedures explained in the enclosed proxy statement/prospectus. Holders of Inland common stock who do not vote in favor of the merger proposal and who submit a written demand for such an appraisal prior to the vote on the merger proposal and comply with the other Maryland law procedures will not receive the merger consideration, but instead will have their Inland common stock converted into the right to receive payment of such appraised value in accordance with Maryland law procedures as explained in the enclosed proxy statement/prospectus.

The enclosed proxy statement/prospectus provides a detailed description of the special meeting, the merger, the documents related to the merger, and other related matters. We urge you to read the proxy statement/prospectus, including any documents incorporated in the proxy statement/prospectus by reference, and its appendices carefully and in their entirety.

If you have any questions concerning the merger, the merger agreement or the proxy statement/ prospectus, would like additional copies of the proxy statement/prospectus without charge or need help voting your shares of Inland common stock, please contact Peter Stickler at (877) 908-6555.

BY ORDER OF THE BOARD OF DIRECTORS,

Peter Stickler
President
Inland Bancorp, Inc.

Oak Brook, Illinois
[•], 2023

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WHERE YOU CAN FIND MORE INFORMATION

Byline Bancorp, Inc.

Byline Bancorp, Inc. (which we refer to as Byline) files annual, quarterly and special reports, proxy statements and other business and financial information with the Securities and Exchange Commission (which we refer to as the SEC). Byline files reports and other business and financial information with the SEC electronically, and the SEC maintains a website located at http://www.sec.gov containing this information. You may also obtain these documents, free of charge, from Byline at its investor relations website, http://www.bylinebancorp.com under the tab “Financial Information” and then under “SEC Filings”.

Byline has filed a registration statement on Form S-4 of which this proxy statement/prospectus forms a part. As permitted by SEC rules, this document does not contain all of the information included in the registration statement or in the exhibits or schedules to the registration statement. You may read and copy the registration statement, including any amendments, schedules and exhibits, at the address set forth below. Statements contained in this document as to the contents of any contract or other documents referred to in this document are not necessarily complete. In each case, you should refer to the copy of the applicable contract or other document filed as an exhibit to the registration statement. This document incorporates by reference documents that Byline has previously filed with the SEC. They contain important information about Byline and its financial condition. For more information, please see the section entitled “Incorporation of Certain Documents by Reference”. These documents are available without charge to you upon written or oral request to Byline’s principal executive offices. The address and telephone number of Byline’s principal executive office is listed below:

Byline Bancorp, Inc.
Attn: Investor Relations
180 North LaSalle Street, Suite 300
Chicago, Illinois 60601
(773) 244-7000

Byline’s common stock is traded on the New York Stock Exchange under the symbol “BY”.

Inland Bancorp, Inc.

Inland Bancorp, Inc., which we refer to as Inland, does not have a class of securities registered under Section 12 of the Securities Exchange Act of 1934, as amended (which we refer to as the Exchange Act), is not subject to the reporting requirements of Section 13(a) or 15(d) of the Exchange Act and, accordingly, does not file documents and reports with the SEC.

If you are an Inland stockholder and have any questions concerning the merger proposal, the merger agreement or the proxy statement/prospectus, would like additional copies of the proxy statement/ prospectus without charge or need help voting your shares of Inland common stock, please contact Peter Stickler at (877) 908-6555 or at the following address:

Inland Bancorp, Inc.
Attn: Peter Stickler
2805 Butterfield Road
Oak Brook, Illinois 60523
(877) 908-6555

To obtain timely delivery of these documents, you must request the information no later than [•], 2023 in order to receive them before Inland’s special meeting of stockholders.

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QUESTIONS AND ANSWERS

The following are some questions that you may have regarding the proposals being considered at the special meeting of stockholders of Inland Bancorp, Inc. (which we refer to as the special meeting). You should carefully read 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 proxy statement/prospectus. See “Incorporation of Certain Documents by Reference” beginning on page [•].

What is the Merger?

Byline Bancorp. Inc., a Delaware corporation (which we refer to as Byline), Butterfield Acquisition Corporation (which we refer to as merger sub) and Inland Bancorp, Inc., a Maryland corporation (which we refer to as Inland), have entered into an Agreement and Plan of Merger, dated as of November 30, 2022, as such agreement may be amended from time to time (which we refer to as the merger agreement). The merger agreement provides that, upon the terms and subject to the conditions set forth in the merger agreement, merger sub will be merged with and into Inland, with Inland as the surviving corporation and wholly owned subsidiary of Byline (which we refer to as the merger). Immediately following the merger, Inland will be merged with and into Byline, with Byline as the surviving corporation (which we refer to as the parent merger). A copy of the merger agreement is attached to this proxy statement/ prospectus as Appendix A. We refer to the time at which the merger becomes effective as the effective time.

Immediately following the parent merger, Inland Bank and Trust (which we refer to as Inland Bank), an Illinois state chartered bank and wholly owned subsidiary of Inland, will merge with and into Byline Bank, an Illinois chartered bank and wholly owned subsidiary of Byline, with Byline Bank as the resulting bank as a wholly owned subsidiary of Byline (which we refer to as the bank merger). Upon completion of the bank merger, Inland Bank’s banking offices will become banking offices of Byline Bank.

Why am I receiving this proxy statement/prospectus?

The board of directors of Inland (which we refer to as the Inland board) is using this proxy statement/prospectus to solicit proxies from Inland’s stockholders in connection with the merger.

In order to complete the merger, Inland’s stockholders must approve the merger agreement. Inland stockholders are also being asked to approve one or more adjournments of the special meeting, if necessary or appropriate, as determined by Inland, including adjournments to permit further solicitation of proxies in favor of the merger agreement. For additional information regarding the proposals to be presented to Inland stockholders, refer to the section entitled “Inland Proposals”. Inland will hold a special meeting to consider and vote on these proposals. This proxy statement/prospectus contains important information about the merger and the special meeting, and you should read it carefully and in its entirety. The enclosed voting materials allow you to vote your shares of Inland common stock, par value $1.00 per share (which we refer to as Inland common stock), without attending the special meeting in person.

We encourage you to submit a proxy to vote your shares of Inland common stock as promptly as possible so that your shares may be represented and voted at the special meeting.

This proxy statement/prospectus is also a prospectus with respect to the offering of shares of Byline common stock, par value $0.01 per share (which we refer to as Byline common stock) to be issued in connection with the merger.

What will Inland stockholders receive in the merger?

If the merger is completed and assuming the consideration is not adjusted pursuant to the terms of the merger agreement as described in this proxy statement/prospectus, each share of Inland common stock outstanding immediately prior to the effective time, other than shares, if any, owned by Inland or

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Byline or as to which statutory appraisal rights have been properly exercised and perfected, will be converted into the right to receive the following (which we refer to as the per share merger consideration):

•

the number of shares of Byline common stock equal to the quotient obtained by dividing (i) 6,389,351 by (ii) the number of shares of Inland common stock issued and outstanding immediately prior to the effective time (which we refer to as the exchange ratio); and

•

a cash payment in the amount equal to the quotient obtained by dividing (i) $22,867,150.20 by (ii) the number of shares of Inland common stock issued and outstanding immediately prior to the effective time (which we refer to as the cash consideration), subject to adjustment in the event the dollar amount of Inland’s tangible common equity at closing is above or below certain thresholds set forth in the merger agreement.

Provided, however, that in the event Inland has less than 33,628,162 shares of common stock issued and outstanding at closing, then (1) the exchange ratio will be equal to 0.19 share of Byline common stock and (2) the cash consideration will be equal to $0.68, for each share of Inland common stock issued and outstanding at closing. Inland stock options will be cancelled and the holder thereof will be entitled to a cash payment pursuant to the terms of the merger agreement.

The merger consideration may be adjusted only under certain limited circumstances as set forth in the merger agreement and as described in the answer to the next question. Based on the closing price of Byline common stock as reported on the NYSE of $22.21 as of November 29, 2022, the trading day prior to the day on which the public announcement of the merger was made, and assuming there are no adjustments pursuant to the merger agreement, the merger consideration represents approximately a 14% cash and 86% stock mix. Inland stockholders also will receive cash in lieu of any fractional shares of Byline common stock that would otherwise be issuable in connection with the merger. For more information on the potential adjustments to the merger consideration and cash in lieu of fractional shares, see “Description of the Merger Agreement — Merger Consideration”.

Is the merger consideration subject to adjustment?

Yes, the merger consideration may be adjusted only under certain limited circumstances as set forth in the merger agreement.

In the event that Inland’s tangible common equity (as calculated pursuant to merger agreement and set forth on Inland’s final closing balance sheet) is less than $135.350 million, then the aggregate cash consideration will be reduced on a dollar-for-dollar basis by the amount of such shortfall.

If Inland’s tangible common equity at closing is greater than $141.350 million, then the aggregate cash consideration will be increased on a dollar-for-dollar basis by the amount that is greater than $141.350 million; provided, that, the amount of such increase will not exceed an amount that would result in either Inland’s counsel or Byline’s counsel being unable to deliver its respective tax opinion under the merger agreement, and the aggregate cash consideration will only be increased to the maximum amount that would allow such opinions to be delivered, with the remaining portion of such increase to be paid in shares of Byline common stock based on the Byline closing price.

For more information on the potential adjustments to the merger consideration, see “Description of the Merger Agreement — Merger Consideration”.

Will the merger consideration be adjusted based on the trading price of Byline’s common stock prior to closing?

No, the merger consideration will not be adjusted solely due to changes in the trading price of Byline common stock prior to the closing of the merger.

What is the value of the merger consideration?

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completion of the merger may be more or less than the current price of Byline common stock or the price of Byline common stock at the time of the special meeting.

How will the stock options of Inland be treated as a result of the merger?

Each Inland stock option that is outstanding immediately prior to the effective time will be cancelled in exchange for a cash payment equal to the product of (A) the difference between (i) the sum of (x) the product of the exchange ratio multiplied by the volume weighted average price of one share of Byline common stock as reported on the NYSE for the five (5) business days ending on the business day immediately prior to the closing date (which we refer to as the Byline closing price) plus (y) the cash consideration, less (ii) the exercise price per share of Inland common stock under such stock option, multiplied by (B) the number of shares of Inland common stock covered by such stock option (each an “Option Payment”). In order to receive the Option Payment, each Inland stock option holder must execute and submit to Inland an option termination agreement which includes a full release of any claims related to such options against Inland and Inland Bank.

When will the merger be completed?

Byline and Inland are working to complete the merger as soon as practicable. Subject to the satisfaction or waiver of the closing conditions described under the section entitled “Description of the Merger Agreement — Conditions to Consummation of the Merger,” including the approval of the merger agreement by Inland stockholders, the parties are seeking to consummate the merger by the second quarter of 2023. However, it is possible that factors outside the control of Byline and Inland could result in the merger being completed at a later time or not at all. There may be a substantial amount of time between the special meeting and the completion of the merger.

Who is entitled to vote?

Holders of record of shares of Inland common stock at the close of business on [•], 2023, which is the date that the Inland board has fixed as the record date for the special meeting, are entitled to vote at the special meeting.

What constitutes a quorum?

A majority of the shares of Inland common stock entitled to vote, represented in person or by proxy, constitutes a quorum for transacting business at the special meeting. Proxies marked as abstaining on any matter to be acted upon by stockholders will be counted as represented at the meeting for purposes of determining the presence or absence of a quorum.

What and I being asked to vote on and why is this approval necessary?

Inland stockholders are being asked to vote on the following proposals:

a proposal to adopt the merger agreement, a copy of which is attached as Appendix A, which we refer to as the merger proposal; and

a proposal to adjourn the special meeting, if necessary or appropriate, as determined by Inland, to solicit additional proxies in favor of the merger proposal, which we refer to as the adjournment proposal.

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Inland stockholder approval is required to complete the merger. Inland will transact no business at the special meeting other than as listed above.

What vote is required to approve each proposal at the special meeting?

The Merger Proposal: Approval of the merger proposal requires the affirmative vote of holders of two-thirds of the outstanding shares of Inland common stock entitled to vote at the special meeting.

The Adjournment Proposal: The adjournment proposal requires the affirmative vote of a majority of the shares having voting power present in person or represented by proxy at a duly held meeting at which a quorum is present.

Are there any voting agreements with existing stockholders?

Yes. Daniel L. Goodwin, Inland’s Chairman and Chief Executive Officer and largest stockholder, in his capacity as a beneficial owner of shares of Inland common stock, has entered into a voting agreement with Byline pursuant to which Mr. Goodwin has agreed to vote all shares of Inland common stock that he beneficially owns and has the power to vote in favor of the merger proposal and any other matter that is required to be approved by the stockholders of Inland to facilitate the transactions contemplated by the merger agreement. Mr. Goodwin also agreed to vote against any proposal made in opposition to the approval of the merger or in competition with the merger agreement and against any other acquisition proposal. As of the close of business on the record date, Mr. Goodwin beneficially owned, in the aggregate, [24,922,465.50] shares of Inland common stock, allowing him to exercise approximately 74.11% of the voting power of Inland common stock.

What does the Inland Board of Directors recommend?

The Inland board unanimously recommends that Inland stockholders vote “FOR” the merger proposal and “FOR” the adjournment proposal.

What do I need to do now?

After carefully reading and considering the information contained in this proxy statement/ prospectus, please vote your shares of Inland common stock as soon as possible so that such shares will be represented at the special meeting. Please follow the instructions set forth on the proxy card or on the voting instruction form provided by the record holder if your shares of Inland common stock are held in the name of your broker, bank or other nominee.

How do I vote?

If you are an Inland stockholder of record as of the close of business on the record date, you may submit your proxy before the special meeting by completing, signing, dating and returning the enclosed proxy card in the enclosed postage-paid envelope.

You may also cast your vote in person at the special meeting.

If your shares of Inland common stock are held in “street name,” through a broker, bank or other nominee, that institution will send you separate instructions describing the procedure for voting such shares. “Street name” stockholders who wish to vote at the meeting will need to obtain a proxy form from their broker, bank or other nominee.

How many votes do I have?

You are entitled to one vote for each share of Inland common stock that you owned as of the close of business on the record date. As of the close of business on the record date, there were approximately 33,628,162 outstanding shares of Inland common stock entitled to vote. As of that date, approximately 81.17% of such outstanding shares of Inland common stock were beneficially owned by the directors and executive officers of Inland and their affiliates.

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When and where is the special meeting?

The special meeting will be held at 2:00 p.m., local time, on [•], [•], 2023, at 2901 Butterfield Road, Oak Brook, Illinois 60523. Subject to space availability, all Inland stockholders as of the close of business on the record date, or their duly appointed proxies, may attend the special meeting. Since seating may be limited, admission to the special meeting will be on a first-come, first-served basis. Registration and seating will begin at [•] p.m., local time.

If my shares are held in “street name” by a broker, bank or other nominee, will my broker, bank or other nominee vote my shares for me?

If your shares of Inland common stock are held in “street name” by a broker, bank or other nominee, you must provide the record holder of your shares with instructions on how to vote your shares. Please follow the voting instructions provided by your broker, bank or other nominee.

Please note that you may not vote shares held in “street name” by returning a proxy card directly to Inland or by voting in person at the special meeting unless you provide a “legal proxy,” which you must obtain from your broker, bank or other nominee.

Brokers who hold shares in “street name” for the beneficial owner of those shares typically have the authority to vote in their discretion on “routine” proposals when they have not received instructions from the beneficial owner. However, brokers are not allowed to exercise their voting discretion with respect to the approval of matters that are “non-routine” without specific instructions from the beneficial owner. Both proposals to be voted on at the special meeting are considered “non-routine” matters and, therefore, brokers, banks and other nominees do not have discretionary voting power on these matters.

If you are an Inland stockholder and you do not instruct your broker, bank or other nominee on how to vote your shares, then your broker, bank or other nominee may not vote your shares on either the merger proposal or the adjournment proposal.

•

For the merger proposal, shares not represented at the special meeting are still considered outstanding and, therefore, will have the same effect as a vote “AGAINST” the proposal. Approval of the merger proposal requires the affirmative vote of holders of two-thirds of the outstanding shares of Inland common stock entitled to vote at the special meeting. Therefore, the failure of a holder of shares of Inland common stock to provide its bank, broker or other nominee with voting instructions will have the same effect as a vote “AGAINST” the merger proposal.

•

The adjournment proposal requires the affirmative vote of a majority of the shares having voting power present in person or represented by proxy at a duly held meeting at which a quorum is present. Your bank, broker or other nominee does not have discretionary authority to vote your shares on the special meeting proposals without your instructions. Consequently, failure to provide instructions to your bank, broker or other nominee on how to vote will result in your shares not being counted as represented for purposes of establishing a quorum at the special meeting. Accordingly, such a failure would have an effect on the outcome of the vote if such failure prevents a quorum from being established.

What if I abstain or do not vote?

For purposes of the special meeting, an abstention occurs when a stockholder attends the special meeting, either in person or represented by proxy, but abstains from voting.

Abstentions will be counted as represented at the special meeting for purposes of determining the presence or absence of a quorum for all matters to be voted on at the special meeting.

For the merger proposal, if an Inland stockholder present in person at the special meeting abstains from voting, or responds by proxy with an “abstain” vote, it will have the same effect as a vote cast “AGAINST” the proposal. If an Inland stockholder is not present in person at the special meeting and does not respond by proxy, it will also have the same effect as a vote cast “AGAINST” the proposal.

The adjournment proposal requires the affirmative vote of the majority of the shares having voting power present in person or represented by proxy at a duly held meeting at which a quorum is present.

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Accordingly, for purposes of the adjournment proposal, abstentions will affect the outcome as they will be counted as shares represented at the meeting, but not voted affirmatively in favor of the adjournment proposal.

What will happen if I return my proxy or voting instruction card without indicating how to vote?

If you hold your shares of Inland common stock in your name as a stockholder of record, and you sign and return your proxy card without indicating how to vote on any particular proposal, the shares of Inland common stock represented by your proxy will be voted “FOR” the merger proposal and “FOR” the adjournment proposal.

If you hold your shares of Inland common stock in “street name” through a broker, bank or other nominee and you do not give your broker, bank or other nominee instructions on how to vote, your broker, bank or other nominee will not be able to vote your shares of Inland common stock on either of the proposals at the special meeting and your shares of Inland common stock will not be represented at the special meeting. For the merger proposal, shares not represented at the special meeting are still considered outstanding and, therefore, will have the same effect as a vote “AGAINST” the proposal. For purposes of the adjournment proposal, shares not represented at the special meeting will not affect the outcome as they will not be deemed to be present at the meeting for purposes of determining the required majority vote.

May I change my vote after I have delivered my proxy or voting instruction card?

Yes. If you hold your shares of Inland common stock in your name as a stockholder of record, you may change your vote at any time before your proxy is voted at the special meeting. You may do so in one of three ways:

•

first, by sending a notice of revocation stating that you would like to revoke your proxy;

•

second, by sending a completed proxy card bearing a later date than your original proxy card; or

•

third, by attending the special meeting and voting in person. Attendance at the special meeting will not in itself constitute the revocation of a proxy.

If you are an Inland stockholder of record and you choose to send a written notice of revocation or to mail a new proxy card, you must submit your notice of revocation or your new proxy to:

Inland Bancorp, Inc.
Attn: Peter Stickler
2805 Butterfield Road
Oak Brook, Illinois 60523
(877) 908-6555

Any proxy that you submitted may also be revoked by voting in person at the special meeting.

If your shares are held in “street name” through a broker, bank or other nominee and you have instructed your nominee how to vote your shares of Inland common stock, you must submit new voting instructions to your nominee. You should follow the instructions you receive from your broker, bank or other nominee in order to change or revoke your vote.

Do I need identification to attend the special meeting in person?

Yes. If you hold your shares of Inland common stock in your name as a stockholder of record and you wish to attend the special meeting and vote in person, please bring valid picture identification.

If your shares are held in “street name” through a broker, bank or other nominee, you may only vote in person at the special meeting if you have proof of ownership of your shares of Inland common stock as of the record date and obtain a valid legal proxy from your broker, bank or other nominee that is the stockholder of record of such shares and present such items at the special meeting. You must also bring valid picture identification.

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Are Inland stockholders entitled to appraisal rights?

Inland stockholders will be entitled to appraisal rights but only if they comply with the Maryland law procedures summarized in the section entitled “The Merger — Dissenters’ Rights”. The entirety of Sections 3-202 through 3-213 of the Maryland General Corporation Law, as amended (which we refer to as the MGCL), is provided on Appendix B to this proxy statement/prospectus. Upon consummation of the merger, any Inland stockholder who has perfected her, his or its appraisal rights will have the right to have a court in Maryland determine the value of each share of stock and to be paid the appraised value determined by the court, which could be more or less than the merger consideration.

What are the material U.S. federal income tax consequences of the merger to U.S. holders of shares of Inland common stock?

The merger and the parent merger (which together we refer to as the “integrated merger”) are intended to constitute a single integrated transaction that for federal income tax purposes will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended (which we refer to as the Code), and the obligation of Byline and Inland to complete the merger is conditioned upon the receipt of legal opinions from their respective counsel to that effect. However, neither Inland nor Byline has requested or received a ruling from the Internal Revenue Service that the integrated merger will qualify as a reorganization. If the integrated merger qualifies as a reorganization for U.S. federal income tax purposes, a U.S. holder of Inland common stock generally will recognize gain (but not loss) upon receipt of Byline common stock and cash (other than cash received in lieu of a fractional share of Byline common stock) in exchange for shares of Inland common stock pursuant to the merger in an amount equal to the lesser of (1) the amount of gain realized (i.e., the excess of the sum of the amount of cash and the fair market value of the Byline common stock received pursuant to the merger over such holder’s adjusted tax basis in the shares of Inland common stock surrendered in the exchange) and (2) the amount of cash received pursuant to the merger (excluding any cash received in lieu of a fractional share of Byline common stock). In addition, a U.S. holder of Inland common stock generally will recognize gain or loss with respect to the cash received in lieu of a fractional share of Byline common stock.

For a more detailed discussion of the material U.S. federal income tax consequences of the integrated merger, please see the section entitled “Material U.S. Federal Income Tax Consequences of the Integrated Merger”.

The tax consequences of the integrated merger to any particular stockholder will depend on that stockholder’s particular facts and circumstances. Accordingly, you are urged to consult your tax advisor to determine your tax consequences from the integrated merger.

What happens if the merger is not completed?

If the merger is not completed, Inland stockholders will not receive any consideration for their shares of Inland common stock that otherwise would have been received in connection with the merger. Instead, Inland will remain an independent company.

What happens if I sell my shares of Inland common stock after the record date but before the special meeting?

The record date of the special meeting is earlier than the date of the special meeting and the date that the merger is expected to be completed. If you sell or otherwise transfer your shares of Inland common stock after the record date but before the date of the special meeting, you will retain your right to vote at the special meeting (provided that such shares remain outstanding on the date of the special meeting), but you will not have the right to receive the merger consideration to be received by Inland stockholders in the merger. In order to receive the merger consideration, you must hold your shares of Inland common stock through completion of the merger.

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Will I be able to sell the shares of Byline common stock that I receive in the merger?

Yes. You may freely trade the shares of Byline common stock issued in the merger, except for shares issued to any stockholder who may be deemed to be an “affiliate” of Byline for purposes of Rule 144 under the Securities Act of 1933, as amended (which we refer to as the Securities Act). Persons who may be deemed to be affiliates of Byline include individuals or entities that control, are controlled by, or are under common control with Byline and may include the executive officers, directors and significant stockholders of Byline.

Are there risks involved in the undertaking the merger?

Yes. In evaluating the merger, Inland stockholders should carefully consider the factors discussed in “Risk Factors” beginning on page [•] and other information about Byline included in the documents incorporated by reference into this proxy statement/prospectus, as well as the information about Inland included in this proxy statement/prospectus.

Should Inland stockholders send in their stock certificates now?

No. Inland stockholders SHOULD NOT send in any stock certificates now. If the merger is approved, transmittal materials with instructions for their completion will be provided to Inland stockholders under separate cover and the stock certificates should be sent at that time.

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

Inland 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. If you are a stockholder of record and your shares are registered in more than one name, you will receive more than one proxy card. If you hold shares of Inland common stock in more than one brokerage account, you may receive a separate voting instruction card for each brokerage account in which you hold such shares. In each case, 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 Inland common stock that you own.

Whom should I contact if I have any questions about the proxy materials or voting?

If you are an Inland stockholder and have any questions about the proxy materials or if you need assistance submitting your proxy or voting your shares or need additional copies of this proxy statement/prospectus or the enclosed proxy card, you should contact Peter Stickler at (877) 908-6555.

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SUMMARY

This summary highlights selected information included in this proxy statement/prospectus and does not contain all of the information that may be important to you. You should read this entire proxy statement/ prospectus and its appendices and the other documents to which the parties refer before you decide how to vote with respect to the proposals. In addition, Byline incorporates by reference important business and financial information about Byline into this proxy statement/prospectus. For a description of this information, please see the section entitled “Incorporation of Certain Documents by Reference”. You may obtain the information Byline has incorporated by reference into this proxy statement/prospectus without charge by following the instructions in the section entitled “Where You Can Find More Information” in the forepart of this proxy statement/prospectus. Each item in this summary includes a page reference directing you to a more complete description of that item.

The Merger and the Merger Agreement (pages [•] and [•])

The terms and conditions of the merger are contained in the merger agreement, a copy of which is attached to this proxy statement/prospectus as Appendix A. The parties encourage you to read the merger agreement carefully, as it is the legal document that governs the merger.

Under the terms of the merger agreement, merger sub will be merged with and into Inland, with Inland as the surviving corporation and wholly owned subsidiary of Byline. Immediately following the merger, Inland will be merged with and into Byline, with Byline as the surviving corporation. Immediately following the parent merger, Inland Bank will merge with and into Byline Bank, with Byline Bank as the resulting bank.

Merger Consideration (page [•])

In the merger, each share of Inland common stock outstanding immediately prior to the effective time, other than shares, if any, owned by Inland or Byline or as to which statutory appraisal rights have been properly exercised and perfected, will be converted into the right to receive (i) the cash consideration, and (ii) a number of shares of Byline common stock equal to the exchange ratio, subject to adjustment as set forth in the merger agreement and as further described in the section entitled “Description of the Merger Agreement — Merger Consideration”. For each fractional share of Byline common stock that would otherwise be issued, Byline will pay cash in an amount equal to the fraction of a share (rounded to the nearest cent) of Byline common stock which the holder would otherwise be entitled to receive multiplied by the Byline closing price. No interest will be paid or accrue on the cash payable to holders in lieu of fractional shares.

Recommendation of the Inland Board of Directors (page [•])

After careful consideration, the Inland board unanimously recommends that Inland stockholders vote “FOR” the merger proposal and “FOR” the adjournment proposal. For a more complete description of Inland’s reasons for the merger and the recommendations of the Inland board, please see the section entitled “The Merger — Recommendation of the Inland Board of Directors and Inland’s Reasons for the Merger”.

Opinion of Inland’s Financial Advisor (page [•])

At the November 14, 2022 meeting of the Inland board, a representative of Inland’s financial advisor, Piper Sandler & Co., which we refer to as Piper Sandler, rendered Piper Sandler’s oral opinion, which was subsequently confirmed by delivery of a written opinion to the Inland board, dated November 14, 2022, as to the fairness, as of such date, from a financial point of view, to the holders of Inland’s outstanding common stock of the merger consideration to be received by such holders in the merger pursuant to the merger agreement, based upon and subject to the qualifications, assumptions and other matters considered in connection with the preparation of its opinion.

The full text of the written opinion of Piper Sandler, dated November 14, 2022, which sets forth, among other things, the various qualifications, assumptions and limitations on the scope of the review undertaken by Piper Sandler, is attached as Appendix C to this proxy statement/prospectus. Piper Sandler

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provided its opinion for the information and assistance of the Inland board (solely in its capacity as such) in connection with, and for purposes of, the Inland board’s consideration of the merger and Piper Sandler’s opinion only addressed whether the merger consideration to be received by the holders of Inland common stock in the merger pursuant to the merger agreement was fair, from a financial point of view, to such holders. The opinion of Piper Sandler does not address any other term or aspect of the merger agreement or the transactions contemplated thereby. Piper Sandler’s opinion does not constitute a recommendation to the Inland board or any holder of Inland common stock as to how the Inland board, such stockholder or any other person should vote or otherwise act with respect to the merger or any other matter.

Inland Special Meeting of Stockholders (page [•])

The special meeting will be held at 2:00 p.m., local time, on [•], [•], 2023, at 2901 Butterfield Road, Oak Brook, Illinois 60523. At the special meeting, holders of shares of Inland common stock will be asked to approve the merger proposal and the adjournment proposal.

The Inland board has fixed the close of business on [•], 2023 as the record date for determining the holders of shares of Inland common stock entitled to receive notice of and to vote at the special meeting. As of the close of business on the record date, there were 33,628,162 shares of Inland common stock outstanding and entitled to vote at the special meeting held by approximately 300 stockholders of record. Each share of Inland common stock entitles the holder to one vote on each proposal to be considered at the special meeting.

As of the close of business on the record date, directors and executive officers of Inland and their affiliates owned and were entitled to vote 27,296,753 shares of Inland common stock, representing approximately 81.17% of the shares of Inland common stock outstanding on that date. As of the close of business on the record date, Byline beneficially held no shares of Inland common stock.

Mr. Goodwin, in his capacity as a beneficial owner of shares of Inland common stock, has entered into a voting agreement with Byline, in which Mr. Goodwin has agreed to vote all shares of Inland common stock that he beneficially owns and has the power to vote in favor of the merger proposal and any other matter that is required to be approved by the stockholders of Inland to facilitate the transactions contemplated by the merger agreement. Mr. Goodwin has also agreed to vote against any proposal made in opposition to the approval of the merger or in competition with the merger agreement and against any other acquisition proposal. As of the close of business on the record date, Mr. Goodwin beneficially owned, in the aggregate, [24,922,465.50] shares of Inland common stock, allowing him to exercise approximately 74.11% of the voting power of Inland common stock.

Approval of the merger proposal requires the affirmative vote of holders of two-thirds of the outstanding shares of Inland common stock entitled to vote at the special meeting. Approval of the adjournment proposal requires the affirmative vote of the majority of the shares having voting power present in person or represented by proxy at a duly held meeting at which a quorum is present.

Interests of Inland Directors and Executive Officers in the Merger (page [•])

In considering the recommendation of the Inland board, Inland stockholders should be aware that the directors and executive officers of Inland have certain interests in the merger that may be different from, or in addition to, the interests of Inland stockholders generally. The Inland board was aware of these interests and considered them, among other matters, in making its recommendation that Inland stockholders vote to approve the merger proposal. These interests include:

•

Certain executive officers and other employees of Inland Bank have outstanding options to purchase shares of Inland common stock, each of which will be cancelled in exchange for a cash payment equal to the product of:

(1)

the difference between (i) the sum of (x) the product of the exchange ratio multiplied by the Byline closing price plus (y) the cash consideration, less (ii) the exercise price per share of such Inland stock option, multiplied by

(2)

the number of shares of Inland common stock covered by such option.

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•

Certain executive officers and other employees of Inland Bank will receive a payment pursuant to his/her existing employment agreement or change in control agreement with Inland Bank in connection with the closing of the merger. Specifically, Peter Stickler, President and CEO of Inland Bank, will receive a change in control payment of $2,055,360, Deborah Bartelt, Executive Vice President of Inland Bank, will receive a change in control payment of $893,241, Paul Berley, Chief Financial Officer of Inland Bank, will receive a change in control payment of $243,750, and Dan Healy, Senior Vice President of Inland Bank, will receive a change in control payment of $252,450;

•

Certain executive officers and other employees of Inland Bank will receive retention cash bonus awards, in an aggregate amount not to exceed $1,178,690, that will be payable on the next regularly scheduled payroll date following the closing date; provided that the employee remains employed through the date of payment;

•

Prior to the effective time but to be effective at the effective time, Byline has agreed to appoint one person, mutually agreed upon by both Inland and Byline, as a director to Byline’s board and to re-nominate such person as a director for a one-year term at each of Byline’s annual meeting of stockholders to be held in 2023 and 2024. If, during this period, such person for any reason ceases to serve as a director or chooses for any reason not to stand for re-election, Byline will promptly appoint another person as a director to Byline’s board, as mutually agreed upon by Inland and Byline. However, in the event that, at any time during this period, Mr. Goodwin’s beneficial ownership of Byline common stock falls below five percent (5%) of the then outstanding shares of Byline common stock, Byline may, but will not be required to, choose not to re-nominate the previously mutually agreed upon director then serving on Byline’s board at the next annual meeting of stockholders; and

•

Inland’s directors and executive officers are entitled to certain continued indemnification and coverage under directors’ and officers’ liability insurance policies post-closing pursuant to the merger agreement.

For a more complete description of the interests of Inland’s directors and executive officers in the merger, see “The Merger — Interests of Inland Directors and Executive Officers in the Merger”.

Management and Board of Directors of Byline After the Merger (page [•])

Except as described above under “— Interests of Inland Directors and Executive Officers in the Merger”, the directors and officers of Byline immediately prior to the effective time will be the directors and officers of the surviving corporation after the merger and parent merger until the earlier of their resignation or removal or until their respective successors are duly appointed and qualified.

Regulatory Approvals Required for the Merger (page [•])

The merger cannot proceed without obtaining all requisite regulatory approvals. Byline and Inland have agreed to use their reasonable best efforts to obtain the required approvals. The merger of Byline and Inland is subject to prior approval of the Board of Governors of the Federal Reserve System (which we refer to as the Federal Reserve) or through delegated authority to the Federal Reserve Bank of Chicago, unless the Federal Reserve waives this requirement pursuant to Regulation Y under the BHC Act. In accordance with Regulation Y, on January 13, 2023, Byline submitted a request to the Federal Reserve Bank of Chicago for a waiver from the requirement under Section 3 of the BHC Act for prior approval of the Federal Reserve. On [•], 2023, the Federal Reserve granted the requested waiver.

Immediately following the completion of the parent merger, Inland Bank will merge with and into Byline Bank, with Byline Bank as the resulting bank. The bank merger will be subject to approval by the Federal Deposit Insurance Corporation, which we refer to as the FDIC, and the Illinois Department of Financial and Professional Regulation, which we refer to as the IDFPR. Byline Bank submitted applications with the FDIC and the IDFPR on January 13, 2023 seeking the necessary approvals for the bank merger. The FDIC approved the bank merger on [•], 2023, and the IDFPR approved the bank merger on [•], 2023. The U.S. Department of Justice has authority to comment on the merger and the bank merger during the regulatory approval process of the FDIC and had fifteen (15) days following the approval by the FDIC on

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[•], 2023 to challenge the merger on antitrust grounds. [The U.S. Department of Justice did not challenge the merger or bank merger during such fifteen (15) day period.]

Neither Byline nor Inland is aware of any material governmental approvals or actions that are required for completion of the merger or bank merger other than those described above, all of which have been obtained. It is presently contemplated that if any such additional governmental approvals or actions are required, those approvals or actions will be sought. However, there can be no assurance that any additional approvals or actions will be obtained.

Conditions to Consummation of the Merger (page [•])

The respective obligation of each party to consummate the merger is subject to the fulfilment or written waiver at or prior to the closing of each of the following conditions:

•

approval of the merger proposal by Inland stockholders;

•

the receipt of regulatory approvals and the expiration of any applicable waiting periods;

•

the shares of Byline common stock to be issued in the merger having been approved for listing on the NYSE, subject to official notice of issuance;

•

the registration statement, of which this proxy statement/prospectus is a part, concerning the Byline common stock issuable pursuant to the merger agreement having been declared effective by the SEC and continuing to be effective as of the effective time; and

•

no order, injunction, decree, statute, rule, regulation or other legal restraint or prohibition preventing or making illegal the consummation of the merger, the bank merger or any of the other transactions contemplated by the merger agreement.

Inland’s obligation to consummate the merger is also subject to the fulfillment or written waiver of each of the following conditions:

•

the accuracy of representations and warranties of Byline in the merger agreement, subject to certain materiality standards;

•

performance by Byline in all material respects of its obligations under the merger agreement; and

•

receipt by Inland of an opinion of its counsel, in form and substance reasonably acceptable to Inland, dated as of the closing date, to the effect that, on the basis of facts, representations and assumptions described in such opinion, for U.S. federal income tax purposes, the merger and the parent merger, taken together, will be treated as a single integrated transaction that qualifies as a “reorganization” within the meaning of Section 368(a) of the Code.

Byline’s obligation to consummate the merger is also subject to the fulfilment or written waiver of each of the following conditions:

•

the accuracy of representations and warranties of Inland in the merger agreement, subject to certain materiality standards, including Inland’s representation and warranty that no material adverse effect with respect to Inland has occurred since [•], 2023;

•

performance by Inland in all material respects of its obligations under the merger agreement;

•

receipt by Byline of an opinion of its counsel, in form and substance reasonably acceptable to Byline, dated as of the closing date, to the effect that, on the basis of facts, representations and assumptions described in such opinion, for U.S. federal income tax purposes, the merger and the parent merger, taken together, will be treated as a single integrated transaction that qualifies as a “reorganization” within the meaning of Section 368(a) of the Code;

•

the holders of no more than 5% in the aggregate of the outstanding shares of Inland common stock electing to exercise their dissenters’ rights;

•

receipt by Inland of certain third party consents;

•

the delivery to Byline from Inland of the certificate or certificates representing the shares of common stock of Inland Bank held by Inland; and

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•

the disposition and winding up of certain Inland Bank assets, including the winding up of Inland Bank’s mortgage division, the disposition and sale of a certain loan previously originated by Inland Bank and the disposition and sale of a certain real estate parcel.

For more information, please see the section entitled “Description of the Merger Agreement — Conditions to Consummation of the Merger”.

Acquisition Proposals (page [•])

Under the terms of the merger agreement, Inland has agreed that it will not and will cause its subsidiaries and affiliates not to:

•

initiate, solicit, knowingly encourage or knowingly facilitate in any way inquiries or proposals with respect to an acquisition proposal; or

•

engage in any negotiations concerning, or provide any confidential nonpublic information to, or have any discussions with, any person relating to an acquisition proposal.

However, the above restriction does not prevent Inland or its board of directors from:

•

providing information in response to a request therefor by a person who has made an unsolicited bona fide written acquisition proposal if Inland receives from the person so requesting such information an executed confidentiality agreement on terms not less restrictive to the other party than those contained in the confidentiality agreement between Byline and Inland; or

•

engaging in any negotiations or discussions with any person who has made an unsolicited bona fide written acquisition proposal;

only if, however, in each case referred to in the bullet points above, (i) the Inland board concludes in good faith (after consultation with outside legal counsel and financial advisor) that (A) such acquisition proposal either constitutes a superior proposal (as defined in the section entitled “Description of the Merger Agreement — Acquisition Proposals”) or would reasonably be expected to result in a superior proposal and (B) the failure to take such action would reasonably be expected to violate the directors’ fiduciary duties under applicable law; and (ii) Inland has provided notice to Byline of its intention to provide information to the person who has made such acquisition proposal, and Inland has provided such information to Byline.

Further, the merger agreement provides that, unless the merger agreement is contemporaneously terminated in accordance with its terms, the Inland board will not cause or permit Inland to enter into any letter of intent, memorandum of understanding, agreement in principle, acquisition agreement, merger agreement or other agreement (other than a confidentiality agreement referred to above) relating to any acquisition proposal.

For more information, please see the section entitled “Description of the Merger Agreement — Acquisition Proposals”.

Termination of the Merger Agreement (page [•])

Byline and Inland may mutually agree in writing to terminate the merger agreement at any time prior to the effective time. Subject to certain conditions described in the merger agreement, either Byline or Inland may also terminate the merger agreement if:

•

Inland stockholders do not adopt the merger agreement by the conclusion of the special meeting;

•

any regulatory authority has denied approval of any of the transactions contemplated by the merger agreement and such denial has become final and non-appealable, or any application for a necessary regulatory approval has been withdrawn at the request of a regulatory authority and such regulatory authority would not accept the re-filing of such application, provided that this right to terminate is not available to a party whose failure to fulfill its covenants under the merger agreement has been the cause of the denial or withdrawal of regulatory approval; or

•

the merger is not completed by the outside date, which is June 30, 2023, or if the sole impediment to closing is receipt of required regulatory approvals, September 30, 2023, provided that this right to

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terminate is not available to a party whose failure to fulfill its covenants under the merger agreement has been the cause of, or materially contributed to, the failure of the merger to be completed before such date.

In addition, Inland may terminate the merger agreement if there is a breach of any of the covenants, agreements, representations or warranties of Byline such that the applicable conditions to Inland’s obligation to close the merger set forth in the merger agreement would not be satisfied, and such breach has not been, or cannot be, cured prior to the earlier of the outside date or thirty (30) days after notice to Byline from Inland.

In addition, Byline may terminate the merger agreement if there is a breach of any of the covenants, agreements, representations or warranties of Inland such that the applicable conditions to Byline’s obligation to close the merger set forth in the merger agreement would not be satisfied, and such breach has not been, or cannot be, cured prior to the earlier of the outside date or thirty (30) days after notice to Inland from Byline.

Byline may also terminate the merger agreement prior to the adoption of the merger agreement by the Inland stockholders, if:

•

the Inland board submits the merger agreement to its stockholders without a recommendation for approval or with material and adverse conditions on such approval, or otherwise withdraws or materially and adversely modifies such recommendation;

•

Inland recommends to its stockholders an acquisition transaction other than the merger;

•

Inland breaches its obligations under the merger agreement to convene the special meeting in accordance with its obligations under the merger agreement prior to the outside date;

•

Inland enters into a definitive agreement with respect to an acquisition proposal other than the merger or recommends to its stockholders an acquisition proposal other than the merger; or

•

Inland materially breaches its “no-shop” obligations under the merger agreement.

For more information, please see the section entitled “Description of the Merger Agreement — Termination of the Merger Agreement”.

Termination Fee (page [•])

Inland has agreed to pay to Byline a cash termination fee in an amount equal to $6,840,000 in the following circumstances:

•

Byline terminates the merger agreement prior to the adoption of the merger agreement by the Inland stockholders because (1) the Inland board (a) submits the merger agreement to its stockholders without a recommendation for approval or with material and adverse conditions on such approval, or otherwise withdraws or materially and adversely modifies such recommendation, (b) recommends to its stockholders an acquisition transaction other than the merger, (c) fails to convene a stockholder meeting to approve the merger agreement in accordance with its obligations under the merger agreement prior to the outside date or (d) enters into a definitive agreement with respect to an acquisition proposal or recommends to its stockholders an acquisition proposal other than the merger or (2) Inland materially breaches its “no shop” covenants set forth in the merger agreement; or

•

a bona fide acquisition proposal is publicly announced or otherwise made known to the Inland board prior to the event giving rise to termination of the merger agreement and (a) the merger agreement is terminated (1) by either Byline or Inland because the merger agreement is not approved by the requisite votes of Inland stockholders by the conclusion of the special meeting, (2) by Byline because Inland has breached a representation, warranty, covenant or agreement or (3) by Byline because closing has not occurred by the outside date and all conditions to Inland’s obligation to close the merger have been satisfied (other than the adoption of the merger agreement by the Inland stockholders and the receipt of the applicable tax opinion from its counsel) and (b) prior to the twelve month anniversary of such termination, Inland consummates, or enters into a definitive agreement to consummate, an acquisition transaction.

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For more information, please see the section entitled “Description of the Merger Agreement — Termination Fee”.

Voting Agreement (page [•])

Mr. Goodwin, in his capacity as a beneficial owner of shares of Inland common stock, has entered into a voting agreement with Byline pursuant to which he has agreed to vote all shares of Inland common stock that he beneficially owns and has the power to vote in favor of the merger proposal and any other matter that is required to be approved by the stockholders of Inland to facilitate the transactions contemplated by the merger agreement. Mr. Goodwin has also agreed to vote against any proposal made in opposition to the approval of the merger or in competition with the merger agreement and against any other acquisition proposal. As of the close of business on the record date, Mr. Goodwin beneficially owned, [24,922,465.50] shares of Inland common stock, allowing him to exercise approximately 74.11% of the voting power of Inland common stock.

For more information, please see the section entitled “Description of the Merger Agreement — Voting Agreement”.

Treatment of Inland Stock Options (page [•])

Accounting Treatment of the Merger (page [•])

For accounting and financial reporting purposes, the merger will be accounted for under the acquisition method of accounting for business combinations in accordance with accounting principles generally accepted in the United States, which we refer to as GAAP.

Material U.S. Federal Income Tax Consequences of the Integrated Merger (page [•])

The integrated merger is intended to constitute a single integrated transaction that for federal income tax purposes will qualify as a reorganization within the meaning of Section 368(a) of the Code. However, neither Inland nor Byline has requested or received a ruling from the Internal Revenue Service that the integrated merger will qualify as a reorganization. If the integrated merger qualifies as a reorganization for U.S. federal income tax purposes, a U.S. holder of Inland common stock who receives Byline common stock and cash (other than cash received in lieu of a fractional share of Byline common stock) in exchange for shares of Inland common stock pursuant to the merger, generally will recognize gain (but not loss) in an amount equal to the lesser of (1) the amount of gain realized (i.e., the excess of the sum of the amount of cash and the fair market value of the Byline common stock received pursuant to the merger over such holder’s adjusted tax basis in the shares of Inland common stock surrendered in the exchange) and (2) the amount of cash received pursuant to the merger (excluding any cash received in lieu of a fractional share of Byline common stock). In addition, a U.S. holder of Inland common stock generally will recognize gain or loss with respect to cash received in lieu of a fractional share of Byline common stock. It is a condition to the completion of the merger that Byline and Inland receive written opinions from their respective counsel to the effect that the integrated merger will qualify as a reorganization within the meaning of Section 368(a) of the Code.

Tax matters are complicated and the tax consequences of the integrated merger to each Inland stockholder may depend on such stockholder’s particular facts and circumstances. Inland stockholders are

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urged to consult their tax advisors to understand fully the tax consequences to them of the integrated merger. For more information, please see the section entitled “Material U.S. Federal Income Tax Consequences of the Integrated Merger”.

Comparison of Stockholders’ Rights (page [•])

The rights of Inland stockholders who continue as Byline stockholders after the merger will be governed by the DGCL, Byline’s amended and restated certificate of incorporation, which we refer to as Byline’s certificate of incorporation, and Byline’s amended and restated bylaws, which we refer to as Byline’s bylaws, rather than by the articles of incorporation and bylaws of Inland. For more information, please see the section entitled “Comparison of Stockholders’ Rights”.

The Parties (page [•])

Byline Bancorp, Inc.
180 North LaSalle Street, Suite 300
Chicago, Illinois 60601
Telephone: (773) 244-7000

Byline is a bank holding company incorporated in the state of Delaware and headquartered in Chicago, Illinois. Byline’s banking subsidiary, Byline Bank, an Illinois state-chartered bank, is a full service commercial bank, and has been a part of the Chicago banking community for over 100 years. Byline Bank offers a broad range of banking products and services to small and medium sized businesses, commercial real estate and financial sponsors and to consumers who generally live or work near its branches. Byline also offers online account opening to consumer and business customers through its website and provides trust and wealth management services to its customers. In addition to its traditional commercial banking business, Byline provides small ticket equipment leasing solutions through Byline Financial Group, a wholly-owned subsidiary of Byline Bank, headquartered in Bannockburn, Illinois, with sales offices in Illinois, and sales representatives in Illinois, Florida, Michigan, New Jersey, and New York. Byline also participates in U.S. government guaranteed lending programs and originate U.S. government guaranteed loans. Byline Bank was the fifth most active originator of Small Business Administration (“SBA”) loans in the country and the most active SBA lender in Illinois and Wisconsin, as reported by the SBA for the fiscal year ended September 30, 2022.

As of December 31, 2022, Byline had consolidated total assets of $7.4 billion, total gross loans and leases outstanding of $5.5 billion, total deposits of $5.7 billion, and total stockholders’ equity of $765.8 million.

Byline common stock is traded on the NYSE under the ticker symbol “BY”.

Inland Bancorp, Inc.
2805 Butterfield Road
Oak Brook, Illinois 60523
Telephone: (877) 908-6555

Inland is a one-bank holding company headquartered in Oak Brook, Illinois founded in 1977. Inland is incorporated under the laws of the State of Maryland. Inland is engaged in the banking business through its wholly- owned subsidiary, Inland Bank and Trust, a full service community bank that offers commercial and retail banking services through its headquarters in Oak Brook and 10 additional bank locations throughout the north and west Chicagoland area.

Inland Bank is principally engaged in the business of attracting deposits from the general public and using such deposits, together with borrowings and other funds, to originate commercial, consumer and mortgage loans. As a locally owned bank that creates financial solutions for individuals, businesses, and nonprofits, Inland Bank delivers the convenient services of a larger bank in a personal, friendly style that lets its customers know they are its top priority.

Inland Bank had total assets of approximately $1.2 billion, total loans of approximately $893.6 million and total deposits of approximately $997.1 million as of December 31, 2022.

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Risk Factors (page [•])

Before voting at the special meeting, you should carefully consider all of the information contained in or incorporated by reference into this proxy statement/prospectus, including the risk factors set forth in the section entitled “Risk Factors” or described in Byline’s Annual Report on Form 10-K for the year ended on December 31, 2021, Byline’s Quarterly Reports on Form 10-Q for the quarters ended March 31, 2022, June 30, 2022 and September 30, 2022, and other reports filed with the SEC, which are incorporated by reference into this proxy statement/prospectus. Please see “Where You Can Find More Information” and “Incorporation of Certain Documents by Reference”.

SELECTED HISTORICAL CONSOLIDATED FINANCIAL INFORMATION FOR BYLINE

The following table summarizes certain selected historical consolidated financial data of Byline for the periods and as of the dates indicated. You should read this in conjunction with Byline’s consolidated financial statements and the notes to the consolidated financial statements contained in reports that Byline has previously filed with the SEC. Historical financial information for Byline can be found in its Annual Report on Form 10-K for the year ended December 31, 2021 and, for the quarter and year-end December 31, 2022 (unaudited) in its Current Report on Form 8-K filed with the SEC on January 26, 2023. The 2018 to 2021 periods reflect the reclassification of the provision for unfunded commitments from other non-interest expense to provision for credit losses to conform to the current presentation. Please see the section entitled “Where You Can Find More Information” for instructions on how to obtain the information that has been incorporated by reference. You should not assume the results of operations for past periods indicate results for any future period. Byline’s management uses the non-GAAP financial measures set forth herein in its analysis of Byline’s performance. Byline believes that these non-GAAP financial measures provide useful information to management and investors, however, you should not view these disclosures as a substitute for results determined in accordance with GAAP financial measures.

	As of or for the year ended December 31,
(dollars in thousands, except share and per share data)	(Unaudited) 2022			2021			2020			2019			2018
Summary of Operations
Net interest income		$	265,330		$	236,387		$	214,978		$	216,285		$	178,605
Provision for credit losses			23,879			973			56,677			20,628			19,112
Non-interest income			57,314			74,253			62,060			55,548			49,575
Non-interest expense			184,082			185,455			168,694			173,910			153,628
Income before provision for income taxes			114,683			124,212			51,667			77,295			55,440
Provision for income taxes			26,729			31,427			14,200			20,293			14,247
Net income			87,954			92,785			37,467			57,002			41,193
Dividends on preferred shares			196			783			783			783			783
Income available to common stockholders			87,758			92,002			36,684			56,219			40,410
Earnings per Common Share
Basic earnings per common share		$	2.37		$	2.45		$	0.96		$	1.51		$	1.21
Diluted earnings per common share			2.34			2.40			0.96			1.48			1.18
Adjusted diluted earnings per share(1)(2)(3)			2.36			2.71			1.05			1.62			1.43
Weighted average common shares outstanding (basic)			36,972,972			37,609,723			38,031,250			37,290,486			33,292,619
Weighted average common shares outstanding (diluted)			37,476,120			38,369,067			38,312,608			37,986,463			34,179,754
Common shares outstanding			37,492,775			37,713,903			38,618,054			38,256,500			36,343,239

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	As of or for the year ended December 31,
(dollars in thousands, except share and per share data)	(Unaudited) 2022			2021			2020			2019			2018
Balance Sheet Data
Loans and leases held for investment, net before allowance for loan and lease losses(4)		$	5,421,258		$	4,537,128		$	4,340,535		$	3,785,661		$	3,501,626
Loans and leases held for sale			47,823			64,460			7,924			11,732			19,827
Allowance for credit losses – loans and leases (ACL)			81,924			55,012			66,347			31,936			25,201
Interest-bearing deposits in other banks			117,079			122,684			41,988			32,509			91,670
Investment securities			1,185,125			1,469,005			1,460,389			1,198,735			916,922
Assets held for sale			8,673			9,153			13,023			15,362			14,489
Other real estate owned, net			4,717			2,112			6,350			9,896			5,041
Goodwill and other intangibles			158,887			165,558			172,631			180,255			161,596
Servicing assets			19,172			23,744			22,042			19,471			19,693
Total assets			7,362,941			6,696,172			6,390,652			5,521,809			4,942,574
Total deposits			5,695,121			5,155,047			4,752,031			4,147,577			3,749,916
Total liabilities			6,597,125			5,859,790			5,585,188			4,771,694			4,291,902
Total stockholders’ equity			765,816			836,382			805,464			750,115			650,672
Deposits per branch			149,872			117,160			103,305			67,993			63,558
Book value per common share			20.43			21.90			20.59			19.33			17.62
Tangible book value per common share(1)			16.19			17.51			16.12			14.62			13.17
Key Ratios and Performance Metrics
Net interest margin			4.00%			3.84%			3.80%			4.47%			4.60%
Cost of deposits			0.36			0.09			0.35			0.91			0.60
Efficiency ratio(5)			54.99			57.42			58.14			61.13			64.86
Adjusted efficiency ratio(1)(5)			54.70			52.14			56.42			58.57			59.37
Non-interest expense to average assets			2.62			2.79			2.75			3.30			3.62
Adjusted non-interest expense to average assets(1)(2)			2.61			2.54			2.67			3.16			3.33
Return on average stockholders’ equity			11.33			11.31			4.78			8.05			7.34
Adjusted return on average stockholders’ equity(1)(2)(3)			11.43			12.77			5.21			8.77			8.85
Return on average assets			1.25			1.40			0.61			1.08			0.97
Adjusted return on average assets(1)(2)(3)			1.26			1.58			0.67			1.18			1.17
Non-interest income to total revenues(1)			17.76			23.90			22.40			20.43			21.73
Pre-tax pre-provision return on average assets(1)			1.97			1.88			1.76			1.86			1.76
Adjusted pre-tax pre-provision return on average assets(1)(2)			1.99			2.13			1.84			1.99			2.05
Return on average tangible common stockholders’ equity(1)			15.15			15.17			7.06			11.80			10.44

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	As of or for the year ended December 31,
(dollars in thousands, except share and per share data)	(Unaudited) 2022		2021		2020		2019		2018
Adjusted return on average tangible common stockholders’ equity(1)(2)(3)		15.28		17.04		7.63		12.78		12.44
Non-interest bearing deposits to total deposits		37.55		41.87		37.09		30.85		31.81
Loans and leases held for sale and loans and leases held for investment to total deposits		96.03%		89.26%		91.51%		91.56%		93.91%
Deposits to total liabilities		86.33		87.97		85.08		86.92		87.37
Asset Quality Ratios
Non-performing loans and leases to total loans and leases held for investment, net before ACL		0.66%		0.51%		0.95%		0.96%		0.74%
ACL to total loans and leases held for investment, net before ACL		1.51		1.21		1.53		0.84		0.72
Net charge-offs to average total loans and leases held for investment		0.16		0.28		0.51		0.37		0.35
Capital Ratios
Common equity to total assets		10.40%		12.33%		12.44%		13.40%		12.95%
Tangible common equity to tangible assets(1)		8.42		10.11		10.01		10.47		10.01
Leverage ratio		10.29		10.89		11.12		11.39		11.05
Common equity tier 1 capital ratio		10.20		11.39		12.20		12.36		11.85
Tier 1 capital ratio		10.85		12.37		13.36		13.67		13.30
Total capital ratio		13.00		14.70		16.18		14.43		13.99

(1)

Represents a non-GAAP financial measure. See ‘‘Reconciliation and Management Explanation of Non-GAAP Financial Measures” for a reconciliation of Byline’s Non-GAAP measures to the most directly comparable GAAP financial measure.

(2)

Calculation excludes impairment charges, merger-related expenses, and core system conversion expenses.

(3)

Calculation excludes incremental income tax expense or benefit related to changes incorporate income tax rates.

(4)

Represents loans and leases, net of acquisition accounting adjustments, unearned deferred fees and costs and initial indirect costs.

(5)

Represents non-interest expense less amortization of intangible assets divided by net interest income and non-interest income.

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GAAP RECONCILIATION AND MANAGEMENT EXPLANATION
OF NON-GAAP FINANCIAL MEASURES

Some of the financial measures included in “Selected Historical Consolidated Financial Information for Byline” are not measures of financial performance in accordance with GAAP. Byline’s management uses the non-GAAP financial measures set forth below in its analysis of Byline’s performance:

•

“Adjusted net income” and “adjusted diluted earnings per share” exclude certain significant items, which include incremental income tax benefit related to federal corporate income tax reductions, impairment charges on assets held for sale and right-of-use asset (‘‘ROU”), merger-related expenses, and core system conversion expenses adjusted for applicable income tax. Byline’s management believes the significant items are not indicative of or useful to measure Byline’s operating performance on an ongoing basis.

•

“Adjusted non-interest expense” is non-interest expense excluding certain significant items, which include impairment charges on assets held for sale and ROU, merger-related expenses, and core system conversion expenses.

•

“Adjusted efficiency ratio” is adjusted non-interest expense less amortization of intangible assets divided by net interest income and non-interest income. Management believes the metric is an important measure of Byline’s operating performance on an ongoing basis.

•

“Adjusted non-interest expense to average assets” is adjusted non-interest expense divided by average assets. Byline’s management believes the metric is an important measure of Byline’s operating performance on an ongoing basis.

•

“Adjusted return on average stockholders’ equity” is adjusted net income divided by average stockholders’ equity. Byline’s management believes the metric is an important measure of Byline’s operating performance on an ongoing basis.

•

“Adjusted return on average assets” is adjusted net income divided by average assets. Byline’s management believes the metric is an important measure of Byline’s operating performance on an ongoing basis.

•

“Non-interest income to total revenues” is non-interest income divided by net interest income plus non-interest income. Byline’s management believes that it is standard practice in the industry to present non-interest income as a percentage of total revenue. Accordingly, Byline’s management believes providing these measures may be useful for peer comparison.

•

“Pre-tax pre-provision net income” is pre-tax income plus the provision for credit losses. Byline’s management believes this metric is important due to the tax benefit resulting from the decrease in the federal corporate income tax rate. The metric demonstrates income excluding the tax provision and excludes the provision for credit losses.

•

“Adjusted pre-tax pre-provision net income” is pre-tax pre-provision net income excluding certain significant items, which include impairment charges on assets held for sale and ROU, merger-related expenses, and core system conversion expenses. Byline’s management believes the metric is an important measure of Byline’s operating performance on an ongoing basis.

•

“Pre-tax pre-provision return on average assets” is pre-tax income plus the provision for credit losses, divided by average assets. Byline’s management believes this ratio demonstrates profitability excluding the tax provision or benefit and excludes the provision for credit losses.

•

“Adjusted pre-tax pre-provision return on average assets” excludes certain significant items, which include impairment charges on assets held for sale and ROU, merger-related expenses, and core system conversion expenses.

•

“Tangible common equity” is defined as total stockholders’ equity reduced by preferred stock and goodwill and other intangible assets. Byline’s management does not consider servicing assets as an intangible asset for purposes of this calculation.

•

“Tangible assets” is defined as total assets reduced by goodwill and other intangible assets. Byline’s management does not consider servicing assets as an intangible asset for purposes of this calculation.

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•

“Tangible book value per common share” is calculated as tangible common equity, which is stockholders’ equity reduced by preferred stock and goodwill and other intangible assets, divided by total shares of common stock outstanding. Byline’s management believes this metric is important due to the relative changes in the book value per share exclusive of changes in intangible assets.

•

“Tangible common equity to tangible assets” is calculated as tangible common equity divided by tangible assets, which is total assets reduced by goodwill and other intangible assets. Byline’s management believes this metric is important to investors and analysts interested in relative changes in the ratio of total stockholders’ equity to total assets, each exclusive of changes in intangible assets.

•

“Tangible net income available to common stockholders” is net income available to common stockholders excluding after-tax intangible asset amortization.

•

“Adjusted tangible net income available to common stockholders” is tangible net income available to common stockholders excluding certain significant items. Byline’s management believes the metric is an important measure of Byline’s operating performance on an ongoing basis.

•

“Return on average tangible common stockholders’ equity” is tangible net income available to common stockholders divided by average tangible common stockholders’ equity. Byline’s management believes the metric is an important measure of Byline’s operating performance on an ongoing basis.

•

“Adjusted return on average tangible common stockholders’ equity” is adjusted tangible net income available to common stockholders divided by average tangible common stockholders’ equity. Byline’s management believes the metric is an important measure of Byline’s operating performance on an ongoing basis.

Byline believes that these non-GAAP financial measures provide useful information to its management and investors that is supplementary to its financial condition, results of operations and cash flows computed in accordance with GAAP; however, Byline acknowledges that its non-GAAP financial measures have a number of limitations. As such, you should not view these disclosures as a substitute for results determined in accordance with GAAP financial measures that Byline and other companies use. Byline’s management also uses these measures for peer comparison.

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The following reconciliation tables provide a more detailed analysis of the non-GAAP financial measures discussed herein:

	As of or for the year ended December 31,
(dollars in thousands, except share and per share data)	(Unaudited) 2022			2021			2020			2019			2018
Net income and earnings per share excluding significant items
Reported Net Income		$	87,954		$	92,785		$	37,467		$	57,002		$	41,193
Significant items:
Incremental income tax benefit attributed to federal income tax reform			—			—			—			—			(724)
Impairment charges on assets held for sale and ROU asset			372			16,430			4,769			569			628
Merger-related expense			538			—			—			4,340			2,056
Core system conversion expense			—			—			—			2,049			9,847
Tax benefit on significant items			(118)			(4,462)			(1,328)			(1,830)			(3,275)
Adjusted net income		$	88,746		$	104,753		$	40,908		$	62,130		$	49,725
Reported Diluted Earnings per Share		$	2.34		$	2.40		$	0.96		$	1.48		$	1.18
Significant items:
Incremental income tax benefit attributed to federal income tax reform		$	—		$	—		$	—		$	—		$	(0.02)
Impairment charges on assets held for sale and ROU asset			0.01			0.43			0.12			0.01			0.02
Merger-related expense			0.01			—			—			0.12			0.06
Core system conversion expense			—			—			—			0.05			0.29
Tax benefit on significant items			—			(0.12)			(0.03)			(0.04)			(0.10)
Adjusted Diluted Earnings per Share		$	2.36		$	2.71		$	1.05		$	1.62		$	1.43
Adjusted non-interest expense:
Non-interest expense		$	184,082		$	185,455		$	168,694		$	173,910		$	153,628
Less significant items:
Impairment charges on assets held for sale and ROU asset			372			16,430			4,769			569			628
Merger-related expense			538			—			—			4,340			2,056
Core system conversion expense			—			—			—			2,049			9,847
Adjusted non-interest expense		$	183,172		$	169,025		$	163,925		$	166,952		$	141,097
Adjusted non-interest expense excluding amortization of intangible assets:
Adjusted non-interest expense		$	183,172		$	169,025		$	163,925		$	166,952		$	141,097
Less: Amortization of intangible assets			6,671			7,073			7,624			7,737			5,629
Adjusted non-interest expense excluding amortization of intangible assets		$	176,501		$	161,952		$	156,301		$	159,215		$	135,468
Pre-tax pre-provision net income:
Pre-tax income		$	114,683		$	124,212		$	51,667		$	77,295		$	55,440
Add: Provision for credit losses			23,879			973			56,677			20,628			19,112
Pre-tax pre-provision net income		$	138,562		$	125,185		$	108,344		$	97,923		$	74,552

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	As of or for the year ended December 31,
(dollars in thousands, except share and per share data)	(Unaudited) 2022			2021			2020			2019			2018
Adjusted pre-tax pre-provision net income:
Pre-tax pre-provision net income		$	138,562		$	125,185		$	108,344		$	97,923		$	74,552
Impairment charges on assets held for sale and ROU asset			372			16,430			4,769			569			628
Merger-related expense			538			—			—			4,340			2,056
Core system conversion expense			—			—			—			2,049			9,847
Adjusted pre-tax pre-provision net income		$	139,472		$	141,615		$	113,113		$	104,881		$	87,083
Total revenues:
Net interest income		$	265,330		$	236,387		$	214,978		$	216,285		$	178,605
Add: Non-interest income			57,314			74,253			62,060			55,548			49,575
Total revenues		$	322,644		$	310,640		$	277,038		$	271,833		$	228,180
Tangible common stockholders’ equity:
Total stockholders’ equity		$	765,816		$	836,382		$	805,464		$	750,115		$	650,672
Less: Preferred stock			—			10,438			10,438			10,438			10,438
Less: Goodwill			148,353			148,353			148,353			148,353			128,177
Less: Core deposit intangibles and other intangibles			10,534			17,205			24,278			31,902			33,419
Tangible common stockholders’ equity		$	606,929		$	660,386		$	622,395		$	559,422		$	478,638
Tangible assets:
Total assets		$	7,362,941		$	6,696,172		$	6,390,652		$	5,521,809		$	4,942,574
Less: Goodwill			148,353			148,353			148,353			148,353			128,177
Less: Core deposit intangibles and other intangibles			10,534			17,205			24,278			31,902			33,419
Tangible assets		$	7,204,054		$	6,530,614		$	6,218,021		$	5,341,554		$	4,780,978
Average tangible common equity:
Average total stockholders’ equity		$	776,225		$	820,017		$	784,578		$	708,200		$	561,568
Less: Average preferred stock			2,459			10,438			10,438			10,438			10,438
Less: Average goodwill			148,353			148,353			148,353			140,087			97,349
Less: Average core deposit intangibles and other intangibles			13,850			20,689			28,095			34,004			27,679
Average tangible common stockholders’ equity		$	611,563		$	640,537		$	597,692		$	523,671		$	426,102
Average tangible assets:
Average total assets		$	7,018,779		$	6,642,131		$	6,140,143		$	5,277,042		$	4,238,602
Less: Average goodwill			148,353			148,353			148,353			140,087			97,349
Less: Average core deposit intangibles and other intangibles			13,850			20,689			28,095			34,004			27,679
Average tangible assets		$	6,856,576		$	6,473,089		$	5,963,695		$	5,102,951		$	4,113,574
Tangible net income available to common stockholders:
Income available to common stockholders		$	87,758		$	92,002		$	36,684		$	56,219		$	40,410
Add: After-tax intangible asset amortization			4,890			5,147			5,501			5,582			4,061
Tangible net income available to common stockholders		$	92,648		$	97,149		$	42,185		$	61,801		$	44,471

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	As of or for the year ended December 31,
(dollars in thousands, except share and per share data)	(Unaudited) 2022			2021			2020			2019			2018
Adjusted tangible net income available to common stockholders
Tangible net income available to common stockholders		$	92,648		$	97,149		$	42,185		$	61,801		$	44,471
Incremental income tax benefit attributed to federal income tax reform			—			—			—			—			(724)
Impairment charges on assets held for sale and ROU asset			372			16,430			4,769			569			628
Merger-related expense			538			—			—			4,340			2,056
Core system conversion expense			—			—			—			2,049			9,847
Tax benefit on significant items		$	(118)		$	(4,462)		$	(1,328)		$	(1,830)		$	(3,275)
Adjusted tangible net income available to common stockholders		$	93,440		$	109,117		$	45,626		$	66,929		$	53,003
Pre-tax pre-provision return on average assets:
Pre-tax pre-provision net income		$	138,562		$	125,185		$	108,344		$	97,923		$	74,552
Total average assets			7,018,779			6,642,131			6,140,143			5,277,042			4,238,602
Pre-tax pre-provision return on average assets			1.97%			1.88%			1.76%			1.86%			1.76%
Adjusted pre-tax pre-provision return on average assets:
Adjusted pre-tax pre-provision net income		$	139,472		$	141,615		$	113,113		$	104,881		$	87,083
Total average assets			7,018,779			6,642,131			6,140,143			5,277,042			4,238,602
Adjusted Pre-tax pre-provision return on average assets			1.99%			2.13%			1.84%			1.99%			2.05%
Non-interest income to total revenues:
Non-interest income		$	57,314		$	74,253		$	62,060		$	55,548		$	49,575
Total revenues			322,644			310,640			277,038			271,833			228,180
Non-interest income to total revenues			17.76%			23.90%			22.40%			20.43%			21.73%
Adjusted non-interest expense to average assets:
Adjusted non-interest expense		$	183,172		$	169,025		$	163,925		$	166,952		$	141,097
Total average assets			7,018,779			6,642,131			6,140,143			5,277,042			4,238,602
Adjusted non-interest expense to average assets			2.61%			2.54%			2.67%			3.16%			3.33%
Adjusted efficiency ratio:
Adjusted non-interest expense excluding amortization of intangible assets		$	176,501		$	161,952		$	156,301		$	159,215		$	135,468
Total revenues			322,644			310,640			277,038			271,833			228,180
Adjusted efficiency ratio			54.70%			52.14%			56.42%			58.57%			59.37%
Adjusted return on average assets:
Adjusted net income		$	88,746		$	104,753		$	40,908		$	62,130		$	49,725
Average total assets			7,018,779			6,642,131			6,140,143			5,277,042			4,238,602
Adjusted return on average assets			1.26%			1.58%			0.67%			1.18%			1.17%
Adjusted return on average stockholders’ equity:
Adjusted net income		$	88,746		$	104,753		$	40,908		$	62,130		$	49,725
Average stockholders’ equity			776,225			820,017			784,578			708,200			561,568
Adjusted return on average stockholders’ equity			11.43%			12.77%			5.21%			8.77%			8.85%

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	As of or for the year ended December 31,
(dollars in thousands, except share and per share data)	(Unaudited) 2022			2021			2020			2019			2018
Tangible common equity to tangible assets:
Tangible common equity		$	606,929		$	660,386		$	622,395		$	559,422		$	478,638
Tangible assets			7,204,054			6,530,614			6,218,021			5,341,554			4,780,978
Tangible common equity to tangible assets			8.42%			10.11%			10.01%			10.47%			10.01%
Return on average tangible common stockholders’ equity:
Tangible net income available to common stockholders		$	92,648		$	97,149		$	42,185		$	61,801		$	44,471
Average tangible common stockholders’ equity			611,563			640,537			597,692			523,671			426,102
Return on average tangible common stockholders’ equity			15.15%			15.17%			7.06%			11.80%			10.44%
Adjusted return on average tangible common stockholders’ equity:
Adjusted tangible net income available to common stockholders		$	93,440		$	109,117		$	45,626		$	66,929		$	53,003
Average tangible common stockholders’ equity			611,563			640,537			597,692			523,671			426,102
Adjusted return on average tangible common stockholders’ equity			15.28%			17.04%			7.63%			12.78%			12.44%
Tangible book value per share:
Tangible common equity		$	606,929		$	660,386		$	622,395		$	559,422		$	478,638
Common shares outstanding			37,492,775			37,713,903			38,618,054			38,256,500			36,343,239
Tangible book value per share		$	16.19		$	17.51		$	16.12		$	14.62		$	13.17

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COMPARATIVE MARKET INFORMATION

Byline Information

Byline common stock is traded on the NYSE under the symbol “BY”. You should obtain current price quotations for Byline common stock.

The following table sets forth the closing sale price per share of Byline common stock on November 29, 2022, the trading day prior to the day on which the public announcement of the signing of the merger agreement was made, and on [•], 2023, the latest practicable date before the date of this proxy statement/prospectus. The following table also includes the equivalent market value per share of Inland common stock on November 29, 2022 and [•], 2023, based on 33,628,162 shares of Inland common stock outstanding as of such dates, determined by adding $0.68 in cash plus the product of the share price of Byline common stock on such dates and the exchange ratio of 0.19.

	Byline Common Stock			Equivalent Market Value per Inland Common Share(1)
November 29, 2022		$	22.21		$	4.90
[•], 2023		$			$

(1)

The information presented does not reflect the actual value of the merger consideration that will be received by holders of Inland common stock in the merger. The exchange ratio is fixed (subject to potential adjustment, as described in “Description of the Merger Agreement — Merger Consideration”) and therefore the value of the merger consideration at the closing of the merger will be based on the price of Byline common stock on the date the merger is completed. The information presented above solely illustrates the implied value of the merger consideration based on the share price of Byline common stock on the dates set forth above.

Inland Information

There is no established public trading market for shares of Inland common stock and no broker makes a market in the stock.

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RISK FACTORS

In addition to the other information contained in or incorporated by reference into this proxy statement/ prospectus, including the matters addressed under the caption entitled “Cautionary Statement Regarding Forward-Looking Statements,” under “Item 1A. Risk Factors” in Byline’s Annual Report on Form 10-K for the year ended December 31, 2021 and under “Item 1A. Risk Factors” in Byline’s Quarterly Reports on Form 10-Q for the quarters ended March 31, 2022, June 30, 2022 and September 30, 2022, Inland stockholders should carefully consider the following factors in deciding whether to vote for Inland’s proposals. Please see the sections entitled “Where You Can Find More Information” and “Incorporation of Certain Documents by Reference”.

Risks Related to the Merger and Byline’s and
Inland’s Businesses upon Completion of the Merger

The value of the merger consideration that consists of Byline common stock will fluctuate based on the trading price of Byline common stock.

The number of shares of Byline common stock to be issued in the merger will not automatically adjust based on the trading price of Byline common stock, and the market value of those shares at the effective time may vary significantly from the current price of Byline common stock or the price of Byline common stock at the time of the special meeting. Accordingly, at the time of the special meeting, Inland stockholders will not know or be able to calculate the market value of the shares of Byline common stock they might receive upon the completion of the merger.

The market price of Byline common stock could be subject to significant fluctuations due to changes in sentiment in the market regarding Byline’s operations or business prospects, including market sentiment regarding Byline’s entry into the merger agreement. These risks may be affected by, among other things:

•

operating results that vary from the expectations of Byline’s management or of securities analysts and investors;

•

operating and securities price performance of companies that investors consider to be comparable to Byline;

•

announcements of strategic developments, acquisitions, dispositions, financings, and other material events by Byline or its competitors; and

•

changes in global financial markets and economies and general market conditions, such as interest or foreign exchange rates, stock, commodity, credit or asset valuations or volatility.

Stock price changes may also result from a variety of other factors, many of which are outside of the control of Byline and Inland, including changes in the business, operations or prospects of Byline or Inland, regulatory considerations, and general business, market, industry or economic conditions. For more information, see “Description of the Merger Agreement — Merger Consideration” and “Description of the Merger Agreement — Termination”.

The merger consideration may be adjusted only under certain limited circumstances as set forth in the merger agreement. In the event that Inland’s tangible common equity (as calculated pursuant to merger agreement and set forth on Inland’s final closing balance sheet) is less than $135.350 million, then the aggregate cash consideration will be reduced on a dollar-for-dollar basis by the amount of such shortfall.

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The market price of Byline common stock after the merger may be affected by factors different from those affecting the shares of Inland or Byline currently.

Upon completion of the merger, holders of Inland common stock will become holders of Byline common stock. Byline’s business differs from that of Inland. Accordingly, the results of operations of the combined company and the market price of Byline 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 Byline and Inland. For a discussion of the business and market of each of Byline and Inland and of some important factors to consider in connection with the business of each of Byline and Inland, please see “Information About the Companies”.

Inland stockholders will have a reduced ownership and voting interest after the merger and will exercise less influence over management.

Upon the completion of the merger, each former Inland stockholder will have a percentage ownership of Byline that is smaller than such stockholder’s current percentage ownership of Inland. Based on the number of issued and outstanding shares of Byline common stock and Inland common stock on [•], 2023, and assuming no adjustment in the number of shares of Byline common stock to be issued as merger consideration pursuant to the merger agreement, stockholders of Inland, as a group, will receive shares in the merger constituting approximately [•]% of Byline common stock expected to be outstanding immediately after the merger (without giving effect to any Byline common stock held by Inland stockholders prior to the merger). As a result, Inland stockholders, as a group, will have less influence on the board of directors, management and policies of Byline following the merger than they now have on the board of directors, management and policies of Inland.

Byline may fail to realize the anticipated benefits of the merger.

Byline and Inland have operated independently and will continue to do so until the completion of the merger. The success of the merger, including anticipated benefits and cost savings, will depend on, among other things, Byline’s ability to successfully combine the businesses of Byline and Inland, including by minimizing any disruptions to the existing customer relationships and business functions of Byline or Inland, and avoiding any inconsistencies in standards, controls, procedures and policies. If Byline is not able successfully to 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 Byline’s business, financial condition, operating results and prospects. Among the factors considered by the boards of directors of each of Byline and Inland in connection with their respective approvals of the merger agreement were the anticipated 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. To review the reasons for the merger in more detail, see “The Merger — Recommendation of the Inland Board of Directors and Inland’s Reasons for the Merger”.

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 bank regulatory agencies and other governmental authorities. In deciding whether to grant regulatory approval, the relevant governmental entities will consider a variety of factors, including the regulatory standing of each of the parties. An adverse condition or development in either party’s regulatory standing or other factors could prevent or delay the receipt of one or more of the required regulatory approvals. Even if granted, the terms and conditions of the approvals may impose requirements, limitations or costs or place restrictions on the conduct of the combined company’s business. Despite the parties’ commitments to use their reasonable best efforts to obtain regulatory approvals, under the terms of the merger agreement, Byline and Inland will not be required to complete the merger if any such approval imposes a burdensome condition. 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

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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. Additionally, the completion of the merger is subject to the satisfaction or waiver of certain other closing conditions, including the absence of certain orders, injunctions or decrees by any governmental authority that would prohibit or make illegal the completion of the merger. Please see the section entitled “Description of the Merger Agreement — Conditions to Consummation of the Merger”.

Because of the closing conditions in the merger agreement and the ability of either Byline or Inland to terminate the merger agreement in specific instances, there can be no assurance when or if the merger will be completed.

The merger agreement is subject to a number of conditions that must be satisfied or waived to complete the merger. Those conditions include, among other things, (i) the accuracy of the other party’s representations and warranties, subject to certain materiality standards, including the accuracy of the other party’s representation and warranty of the absence of a material adverse effect on the other party since December 31, 2021, (ii) the other party’s performance in all material respects of its obligations under the merger agreement, (iii) the adoption of the merger agreement and the transactions contemplated thereby by Inland stockholders, (iv) the absence of any proceeding in connection with, or that could prevent, delay, make illegal or interfere with, any of the transactions contemplated by the merger agreement, (v) the receipt of required regulatory approvals, including the approval of certain federal and state banking agencies, (vi) the effectiveness of the registration statement of which this proxy statement/prospectus forms a part, (vii) the receipt by each party of an opinion from such party’s counsel to the effect that the integrated merger qualifies as a “reorganization” within the meaning of Section 368(a) of the Code, and (viii) the approval for listing on the NYSE of the shares of Byline common stock issuable in the merger.

In addition, Byline’s obligation to complete the merger is subject to dissenters’ rights having been exercised by the holders of no more than 5% of Inland common stock, receipt by Inland of certain third party consents and the delivery to Byline from Inland of the certificate or certificates representing the shares of common stock of Inland Bank held by Inland. 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 the required Inland stockholder approval, or Byline or Inland may elect to terminate the merger agreement in certain other circumstances. Please see the section entitled “Description of the Merger Agreement — Termination”.

Termination of the merger agreement could negatively affect Inland.

If the merger agreement is terminated there may be various adverse consequences to Inland. For example, Inland’s business may have been adversely affected by the failure to pursue other beneficial opportunities due to the focus of management on the merger, without realizing any of the anticipated benefits of completing the merger. In addition, if the merger agreement is terminated and the Inland board seeks another merger or business combination, Inland stockholders cannot be certain that Inland will be able to find a party willing to offer equivalent or more attractive consideration than the consideration Byline has agreed to provide in the merger, or that such other merger or business combination will be completed. Additionally, if the merger agreement is terminated, under certain circumstances Inland may be required to pay Byline a termination fee of $6,840,000. Please see the section entitled “Description of the Merger Agreement — Termination Fee”.

Inland directors and executive officers have interests in the merger different from or in addition to the interests of Inland stockholders generally.

The interests of some of the directors and executive officers of Inland may be different from those of Inland stockholders generally. While the Inland board knew about and considered these interests when making its decision to approve the merger agreement and in recommending that Inland stockholders vote in favor of adopting the merger agreement, Inland stockholders should consider these interests when determining whether to vote to adopt the merger agreement. Please see the section entitled “The Merger — Interests of Inland Directors and Executive Officers in the Merger”.

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The merger agreement contains provisions that may discourage other companies from trying to acquire Inland for greater merger consideration.

The merger agreement contains provisions that may discourage a third party from submitting a business combination proposal to Inland that might result in greater value to Inland stockholders than the proposed merger with Byline or may result in a potential competing acquirer proposing to pay a lower per share price to acquire Inland than it might otherwise have proposed to pay absent such provisions. These provisions include a general prohibition on Inland from soliciting, or entering into discussions with any third party regarding, any acquisition proposal or offers for competing transactions, subject to certain exceptions relating to the exercise of fiduciary duties by the Inland board. In addition, Inland may be required to pay Byline a termination fee of $6,840,000 upon termination of the merger agreement in certain circumstances involving acquisition proposals for competing transactions. Please see the sections entitled “Description of the Merger Agreement — Termination” and “Description of the Merger Agreement — Termination Fee”.

The opinion of Inland’s financial advisor delivered to the Inland board prior to the signing of the merger agreement does not reflect changes in circumstances between the date of the opinion and the completion of the merger.

On November 14, 2022, the Inland board received an opinion from Piper Sandler, its financial advisor, as to the fairness, as of such date, from a financial point of view, to the holders of Inland’s outstanding common stock of the merger consideration to be received by such holders in the merger pursuant to the merger agreement, based upon and subject to the qualifications, assumptions and other matters considered in connection with the preparation of its opinion. Piper Sandler’s written opinion was delivered to the Inland board on November 14, 2022. Changes in the operations and prospects of Inland or Byline may significantly alter the value of Inland or the price of Byline common stock by the time the merger is completed. The opinion does not speak as of the date of this proxy statement/prospectus or the time the merger will be completed or as of any date other than the date of such opinion.

For a description of the opinion that Inland received from its financial advisor, please refer to the section entitled “The Merger — Opinion of Inland’s Financial Advisor”. A copy of Piper Sandler’s opinion is also attached to this proxy statement/prospectus as Appendix C.

Byline and Inland will incur transaction and integration costs in connection with the merger.

Each of Byline and Inland has incurred and expects that it will incur significant, nonrecurring costs in connection with consummating the merger. In addition, Byline will incur integration costs following the completion of the merger, 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 “— Byline may fail to realize the anticipated benefits of the merger”. Byline and Inland may also incur additional costs to maintain employee morale and to retain key employees. Byline and Inland 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 Byline common stock to be received by Inland stockholders in the merger will have different rights from the shares of Inland common stock.

Upon completion of the merger, Inland stockholders will receive merger consideration consisting, in part, of Byline common stock and will become Byline stockholders and their rights as stockholders will be governed by the DGCL and Byline’s certificate of incorporation and bylaws. The rights associated with Inland common stock are different from the rights associated with Byline common stock. Please see the section entitled “Comparison of Stockholders’ Rights” for a discussion of the different rights associated with Byline common stock.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This proxy statement/prospectus contains certain forward-looking information about Byline, Inland, and the combined corporation after the close of the merger, the anticipated benefits and related expenses to be incurred in connection with the merger and the integration of the companies’ businesses, as well as certain information about the businesses and strategies of Byline and Inland that is intended to be covered by the safe harbor for “forward-looking statements” provided by the Private Securities Litigation Reform Act of 1995. All statements other than statements of historical fact are forward-looking statements and forward looking statements can be identified by use of the words such as “will,” “believe,” “expect,” “intend,” “anticipate,” “estimate,” “project” or similar expressions. Such statements involve inherent risks, uncertainties and contingencies, many of which are difficult to predict and are generally beyond the control of Byline, Inland and the combined corporation. Readers are cautioned that a number of important factors could cause actual results to differ materially from those expressed in, or implied or projected by, such forward-looking statements. In addition to factors previously disclosed in reports filed by Byline with the SEC, risks and uncertainties for each institution and the combined institution include, but are not limited to:

•

the possibility that any of the anticipated benefits of the proposed transactions between Byline and Inland will not be realized or will not be realized within the expected time period;

•

the risk that integration of the operations of Inland with Byline will be materially delayed or will be more costly or difficult than expected;

•

deposit attrition, customer loss or revenue loss following the merger may occur or be greater than expected;

•

the inability to complete the proposed transactions due to the failure to obtain the Inland stockholder approval;

•

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

•

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

•

the effect of the announcement of the transaction on 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 potential risk of diverting management attention and resources from the operation of Byline’s business towards the completion of the merger and other integration efforts;

•

risks related to Byline’s acquisition strategy, including its ability to identify suitable acquisition candidates, exposure to potential asset and credit quality risks and unknown or contingent liabilities, the time and costs of integrating systems, procedures and personnel, the need for capital to finance such transactions, and possible failures in realizing the anticipated benefits from acquisitions;

•

business and economic conditions, particularly those affecting the financial services industry and those in the market areas of Byline and Inland;

•

the ability of Byline and Inland to successfully manage their respective credit risks and the sufficiency of their respective allowances for loan loss;

•

factors that can affect the performance of Byline and Inland’s respective loan portfolios, including real estate values and liquidity in primary market areas, the financial health of commercial borrowers and the success of construction projects that they finance, including any loans acquired in acquisition transactions;

•

compliance with governmental and regulatory requirements, including the Dodd-Frank Wall Street Reform and Consumer Protection Act and others relating to banking, consumer protection, securities and tax matters, and the ability to maintain licenses required in connection with SBA and other government lending programs;

•

legislative and regulatory changes;

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•

the ability to identify and address cyber-security risks, fraud and systems errors;

•

the ability of Byline effectively to execute its strategic plan and manage its growth;

•

the effects of the accounting treatment for loans acquired in connection with acquisitions;

•

changes in the senior management team and the ability to attract, motivate and retain qualified personnel;

•

monetary and fiscal policies of the U.S. government, including policies of the U.S. Department of the Treasury, referred to as the Treasury, and the Federal Reserve, and changes in market interest rates;

•

liquidity issues, including fluctuations in the fair value and liquidity of the securities held for sale and the ability to raise additional capital, if necessary;

•

effects of competition from a wide variety of local, regional, national and other providers of financial, banking, investment and insurance services and demand for financial services in the market areas of Byline and Inland;

•

changes in federal or state tax law or policy;

•

the quality or composition of Byline’s and Inland’s loan or investment portfolios and the valuation of those investment portfolios;

•

demand for loan products and deposit flows; and

•

accounting principles, policies and guidelines.

All forward-looking statements included in this proxy statement/prospectus are based on information available at the time of the proxy statement/prospectus. Projected or estimated numbers are used for illustrative purposes only and are not forecasts, and actual results may differ materially. A number of important factors could cause actual results to differ materially from those indicated in these forward-looking statements, including those factors identified in “Risk Factors” in “Item 1A. Risk Factors” of Byline’s 2021 Annual Report, which is incorporated by reference herein, as such factors may be updated from time to time in Byline’s filings with the SEC.

Byline and Inland are under no obligation to (and expressly disclaim any such obligation to) update or alter these forward-looking statements, whether as a result of new information, future events or otherwise except as required by law.

INLAND SPECIAL MEETING OF STOCKHOLDERS

Date, Time and Place

The special meeting will be held at 2:00 p.m., local time, on [•], [•], 2023, at 2901 Butterfield Road, Oak Brook, Illinois 60523. On or about [•], 2023, Inland commenced mailing of this proxy statement/prospectus and the enclosed form of proxy to its stockholders entitled to vote at the special meeting.

Purpose of the Special Meeting

At the special meeting, Inland stockholders will be asked to consider and vote upon the following proposals:

•

Merger Proposal. To approve the merger of merger sub with and into Inland with Inland as the surviving corporation, and wholly owned subsidiary of Byline, immediately followed by the merger of Inland with and into Byline, with Byline as the surviving corporation, pursuant to the merger agreement, dated as of November 30, 2022, by and among Byline, Butterfield Acquisition Corporation and Inland, as such agreement may be amended from time to time, a copy of which is attached as Appendix A to this proxy statement/prospectus; and

•

Adjournment Proposal. To approve one or more adjournments of the special meeting, if necessary or appropriate, including adjournments to permit further solicitation of proxies if there are insufficient votes at the time of the special meeting to approve the merger proposal.

Inland will transact no other business at the special meeting other than as listed above.

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Recommendation of the Inland Board of Directors

After careful consideration, the Inland board has unanimously approved the merger agreement and the transactions contemplated thereby, and unanimously determined that the merger agreement and the transactions contemplated thereby are fair to and in the best interests of Inland and its stockholders.

The Inland board recommends that you vote “FOR” the merger proposal and “FOR” the adjournment proposal. Please see the section entitled “The Merger — Recommendation of the Inland Board of Directors and Inland’s Reasons for the Merger”.

Record Date and Quorum

As of the close of business on the record date, there were 33,628,162 shares of Inland common stock outstanding and entitled to vote at the special meeting held by approximately 300 stockholders of record. Each share of Inland common stock entitles the holder to one vote on each proposal to be considered at the special meeting.

A majority of shares entitled to vote, represented in person or by proxy, constitutes a quorum for transacting business at the special meeting. Abstentions will be counted as represented at the special meeting for purposes of determining the presence or absence of a quorum for all matters voted on at the special meeting.

None of the proposals to be voted on at the special meeting are routine matters for which brokers may have discretionary authority to vote. Consequently, failure to provide instructions to your bank, broker or other nominee on how to vote will result in your shares not being counted as represented for purposes of establishing a quorum at the special meeting. Accordingly, such a failure would have an effect on the outcome of the vote if such failure prevents a quorum from being established. Please see “— Shares Held in ‘Street Name”‘ below for further information.

As of the close of business on the record date, directors and executive officers of Inland owned and were entitled to vote 27,296,753 shares of Inland common stock, representing approximately 81.17% of the shares of Inland common stock outstanding on that date. As of the close of business on the record date, Byline beneficially held no shares of Inland common stock.

Mr. Goodwin, in his capacity as a beneficial owner of shares of Inland common stock, has entered into a voting agreement with Byline in which Mr. Goodwin has agreed to vote all shares of Inland common stock that he beneficially owns and has the power to vote in favor of the merger proposal and any other matter that is required to be approved by the stockholders of Inland to facilitate the transactions contemplated by the merger agreement. Mr. Goodwin has also agreed to vote against any proposal made in opposition to the approval of the merger or in competition with the merger agreement and against any other acquisition proposal. As of the close of business on the record date, Mr. Goodwin beneficially owned, in the aggregate, [24,922,465.50] shares of Inland common stock, allowing him to exercise approximately 74.11% of the voting power of Inland common stock.

Required Vote

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Merger Proposal: Approval of the merger proposal requires the affirmative vote of holders of two-thirds of the outstanding shares of Inland common stock entitled to vote at the special meeting.

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Adjournment Proposal: The adjournment proposal requires the affirmative vote of the majority of the shares having voting power present in person or represented by proxy at a duly held meeting at which a quorum is present.

Treatment of Abstentions; Failure to Vote

For purposes of the special meeting, an abstention occurs when an Inland stockholder attends the special meeting, either in person or represented by proxy, but abstains from voting.

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Abstentions will be counted as represented at the special meeting for purposes of determining the presence or absence of a quorum for all matters voted on at the special meeting.

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For the merger proposal, if an Inland stockholder present in person at the special meeting abstains from voting, or responds by proxy with an “abstain” vote, it will have the same effect as a vote “AGAINST” the proposal. If an Inland stockholder is not present in person at the special meeting and does not respond by proxy, it will also have the same effect as a vote “AGAINST” the merger proposal.

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The adjournment proposal requires the affirmative vote of the majority of the shares having voting power present in person or represented by proxy at a duly held meeting at which a quorum is present. Accordingly, for purposes of the adjournment proposal, abstentions will affect the outcome as they will be counted as shares represented at the meeting, but not voted affirmatively in favor of the adjournment proposal.

Voting on Proxies; Incomplete Proxies

Giving a proxy means that a stockholder authorizes the persons named in the proxy to vote such holder’s shares at the special meeting in the manner such holder directs. An Inland stockholder may vote by proxy or in person at the special meeting.

The method of voting by proxy differs for shares held by stockholders of record and shares held in “street name”.

Stockholders of Record

If your shares of Inland common stock are registered directly in your name, you are considered the stockholder of record with respect to these shares. If you hold your shares in your name as a stockholder of record, you may submit your proxy before the special meeting by mail. You must complete, sign, date and return the proxy card in the enclosed envelope. The envelope requires no additional postage if mailed in the United States.

You may also cast your vote in person at the special meeting. Please see “— Attending the Special Meeting and Voting in Person” below for further information.

Inland

	Page
Questions and Answers		1
Summary		9
Selected Historical Consolidated Financial Information for Byline		17
GAAP Reconciliation and Management Explanation of Non-GAAP Financial Measures		20
Comparative Market Information		26
Risk Factors		27
Cautionary Statement Regarding Forward-Looking Statements		31
Inland Special Meeting of Stockholders		32
Information about the Companies		37
The Merger		39
Description of the Merger Agreement		62
Material U.S. Federal Income Tax Consequences of the Integrated Merger		77
Comparison of Stockholders’ Rights		80
Description of Byline’s Capital Stock		85
Security Ownership of Certain Beneficial Owners and Management		88
Experts		89
Legal Opinions		89
Inland Annual Meeting Stockholder Proposals		89
Incorporation of Certain Documents by Reference		90
Appendix A: Agreement and Plan of Merger		A-1
Appendix B: Sections 3-202 through 3-213 of the Maryland General Corporation Law		B-1
Appendix C: Opinion of Piper Sandler & Co		C-1
Part II – Information Not Required in Prospectus		II-1