8-K

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT
PURSUANT TO SECTION 13 OR 15(d)
OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): January 25, 2019

BYLINE BANCORP, INC.

(Exact Name of Registrant as Specified in Its Charter)

Delaware

(State or Other Jurisdiction of Incorporation)

001-3813936-3012593
(Commission File Number)(I.R.S. Employer Identification No.)180 North LaSalle Street, Suite 300
Chicago, Illinois60601
(Address of Principal Executive Offices)(Zip Code)

(773) 244-7000

Registrant’s Telephone Number, Including Area Code)

Not Applicable
(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter)

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 13(a) of the Exchange Act.     ☐

Item 7.01. Regulation FD Disclosure.

On January 25, 2019, the Company made available on its website a slide presentation regarding the Company’s fourth quarter 2018 financial results, which will be used as part of a publicly accessible conference call on January 25, 2019.  A copy of the slide presentation is attached as Exhibit 99.1 and is incorporated herein by reference.

The information in this Form 8-K and the attached exhibits is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in any such filing.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

Exhibit No.	Description
99.1	Slide Presentation regarding fourth 2018 financial results

Forward-Looking Statements

This communication contains forward-looking statements within the meaning of the U.S. federal securities laws. Forward-looking statements include, without limitation, statements concerning plans, estimates, calculations, forecasts and projections with respect to the anticipated future performance of the Company. These statements are often, but not always, made through the use of words or phrases such as ‘‘may’’, ‘‘might’’, ‘‘should’’, ‘‘could’’, ‘‘predict’’, ‘‘potential’’, ‘‘believe’’, ‘‘expect’’, ‘‘continue’’, ‘‘will’’, ‘‘anticipate’’, ‘‘seek’’, ‘‘estimate’’, ‘‘intend’’, ‘‘plan’’, ‘‘projection’’, ‘‘would’’, ‘‘annualized’’, “target” and ‘‘outlook’’, or the negative version of those words or other comparable words or phrases of a future or forward-looking nature. Forward-looking statements involve estimates and known and unknown risks, and reflect various assumptions and involve elements of subjective judgement and analysis, which may or may not prove to be correct, and which are subject to uncertainties and contingencies outside the control of Byline and its respective affiliates, directors, employees and other representatives, which could cause actual results to differ materially from those presented in this communication. No representations, warranties or guarantees are or will be made by Byline as to the reliability, accuracy or completeness of any forward-looking statements contained in this communication or that such forward-looking statements are or will remain based on reasonable assumptions. You should not place undue reliance on any forward-looking statements contained in this communication.

In addition, this communication contains forward-looking statements related to the pending merger of Byline and Oak Park River Forest Bankshares, Inc., including, but not limited to, with respect to the expected completion date, financial benefits and other effects of the transaction. Factors that could cause actual results to differ materially from those presented in this communication regarding the pending merger may include, but are not limited to, the reaction to the transaction of the companies’ customers, employees, and counterparties; customer disintermediation; inflation; expected synergies, costs savings, and other financial benefits of the proposed transaction that might not be realized within the expected timeframes or might be less than projected; the requisite Oak Park River Forest Bankshares, Inc. stockholder approval for the proposed transaction might not be obtained; credit and interest rate risks associated with Byline’s and Oak Park River Forest Bankshares, Inc.’s respective businesses, customers, borrowings, repayment, investment, and deposit practices; general economic conditions, either nationally or in the market areas in which Byline and Oak Park River Forest Bankshares, Inc. operate or anticipate doing business, are less favorable than expected; new regulatory or legal requirements or obligations, and other risks.

Certain risks and important factors that could affect Byline’s future results are identified in its Annual Report on Form 10-K and other reports filed with the Securities and Exchange Commission, including among other things under the heading “Risk Factors” in such Annual Report on Form 10-K.  Any forward-looking statement speaks

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only as of the date on which it is made, and Byline undertakes no obligation to update any forward-looking statement, whether to reflect events or circumstances after the date on which the statement is made, to reflect new information or the occurrence of unanticipated events, or otherwise unless required under the federal securities laws.

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Date: January 25, 2019 BYLINE BANCORP, INC. By:/s/ Alberto J. Paracchini
Name: Alberto J. Paracchini
Title: President and Chief Executive Officer

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EX-99.1

Q4 2018 Financial Results Exhibit 99.1

Forward-Looking Statements This communication contains forward-looking statements within the meaning of the U.S. federal securities laws. Forward-looking statements include, without limitation, statements concerning plans, estimates, calculations, forecasts and projections with respect to the anticipated future performance of the Company. These statements are often, but not always, made through the use of words or phrases such as ‘‘may’’, ‘‘might’’, ‘‘should’’, ‘‘could’’, ‘‘predict’’, ‘‘potential’’, ‘‘believe’’, ‘‘expect’’, ‘‘continue’’, ‘‘will’’, ‘‘anticipate’’, ‘‘seek’’, ‘‘estimate’’, ‘‘intend’’, ‘‘plan’’, ‘‘projection’’, ‘‘would’’, ‘‘annualized’’, “target” and ‘‘outlook’’, or the negative version of those words or other comparable words or phrases of a future or forward-looking nature. Forward-looking statements involve estimates and known and unknown risks, and reflect various assumptions and involve elements of subjective judgement and analysis, which may or may not prove to be correct, and which are subject to uncertainties and contingencies outside the control of Byline and its respective affiliates, directors, employees and other representatives, which could cause actual results to differ materially from those presented in this communication. No representations, warranties or guarantees are or will be made by Byline as to the reliability, accuracy or completeness of any forward-looking statements contained in this communication or that such forward-looking statements are or will remain based on reasonable assumptions. You should not place undue reliance on any forward-looking statements contained in this communication. In addition, this communication contains forward-looking statements related to the pending merger of Byline and Oak Park River Forest Bankshares, Inc., including, but not limited to, with respect to the expected completion date, financial benefits and other effects of the transaction. Factors that could cause actual results to differ materially from those presented in this communication regarding the pending merger may include, but are not limited to, the reaction to the transaction of the companies’ customers, employees, and counterparties; customer disintermediation; inflation; expected synergies, costs savings, and other financial benefits of the proposed transaction that might not be realized within the expected timeframes or might be less than projected; the requisite Oak Park River Forest Bankshares, Inc. stockholder approval for the proposed transaction might not be obtained; credit and interest rate risks associated with Byline’s and Oak Park River Forest Bankshares, Inc.’s respective businesses, customers, borrowings, repayment, investment, and deposit practices; general economic conditions, either nationally or in the market areas in which Byline and Oak Park River Forest Bankshares, Inc. operate or anticipate doing business, are less favorable than expected; new regulatory or legal requirements or obligations, and other risks. Certain risks and important factors that could affect Byline’s future results are identified in its Annual Report on Form 10-K and other reports filed with the Securities and Exchange Commission, including among other things under the heading “Risk Factors” in such Annual Report on Form 10-K. Any forward-looking statement speaks only as of the date on which it is made, and Byline undertakes no obligation to update any forward-looking statement, whether to reflect events or circumstances after the date on which the statement is made, to reflect new information or the occurrence of unanticipated events, or otherwise unless required under the federal securities laws. Additional Information and Where to Find It In connection with the proposed merger transaction involving Byline and Oak Park River Forest Bankshares, Inc. (“Oak Park”), Byline filed a registration statement on Form S 4 with the SEC, which includes a proxy statement of Oak Park and a prospectus of Byline, and Byline will file other documents regarding the proposed transaction with the SEC. The registration statement has not yet become effective. A definitive proxy statement/prospectus will also be sent to Oak Park stockholders seeking the required stockholder approval of the proposed transaction. Before making any voting or investment decision, investors and security holders of Oak Park are urged to carefully read the entire registration statement on Form S-4 initially filed by Byline on January 9, 2019 that includes a proxy statement/prospectus, as well as any amendments or supplements thereto and any other relevant documents that are filed or will be filed with the SEC, because they contain or will contain important information about the proposed transaction. The documents filed by Byline with the SEC may be obtained free of charge at the SEC’s website at www.sec.gov. In addition, the documents filed by Byline may be obtained free of charge at its website at http://www.bylinebancorp.com. Alternatively, these documents, when available, can be obtained free of charge from Byline upon written request to Byline Bancorp, Inc., Attn: Corporate Secretary, 180 North LaSalle Street, 3rd Floor, Chicago, Illinois 60601. Information regarding the interests of certain of Oak Park’s directors and executive officers and a description of their direct and indirect interests, by security holdings or otherwise, is included in the registration statement on Form S-4 initially filed by Byline on January 9, 2019. Participants in the Solicitation Byline, Oak Park River Forest Bankshares, Inc., their respective directors and executive officers and certain of their other members of management and employees may be deemed to be participants in the solicitation of proxies from Oak Park River Forest Bankshares’, Inc. stockholders in connection with the proposed transaction. Information about the directors and executive officers of Byline may be found in Byline’s Annual Report on Form 10-K for the year ended December 31, 2017, as amended by its Form 10-K/A filed with the SEC on April 30, 2018, a copy of which can be obtained free of charge from Byline or from the SEC’s website as indicated above. In addition, information about the directors and executive officers of Byline and Oak Park River Forest Bankshares, Inc. and other persons who may be deemed participants in the transaction will be included in the proxy statement/prospectus and other relevant materials when filed with the SEC.

Fourth Quarter 2018 Highlights Loan Production Earnings Revenue Deposits $164.9 million of loan and lease originations, compared with $218.1 million in prior quarter Net loan growth of $45.8 million, up 5.3% annualized Elevated payoff activity compared to 3Q18 Strong loan balance growth particularly in Commercial Banking Total revenue of $67.8 million, an increase of 6.4% from 3Q18, driven by loan volume and solid fee income levels Net interest income up 1.3% due to higher average loan balances, offset by decline in accretion income NIM (excluding accretion income) 1 increased 14 bps to 4.13% from 3.99% in 3Q18 Non-interest income increased 30.7% driven by an increase in gain on sale revenue as a result of higher volume of loans sold Total deposits of $3.7 billion, up $9.1 million versus 3Q18 Non interest bearing deposits increased $17.7 million for the quarter and accounted for 31.8% of total deposits Deposit balances at former First Evanston branches finished the year higher than at closing of merger Efficiency Net income of $17.1 million, or $0.46 per diluted share, a record since our initial public offering in 2017 Asset impairment charges, merger-related, and core system conversion expense impacted EPS by $0.03 ROAA of 1.39% and ROATCE of 15.49%1 Pre-tax pre-provision ROA1 of 2.23% compared to 2.13% in 3Q18 and 1.73% in 4Q17 Efficiency Ratio remained steady 56.81%; Adjusted Efficiency Ratio1 improved to 54.95% from 55.78% in 3Q18 and 63.23% in 4Q17 Revenue growth of 6.4% outstripped adjusted expense growth of 4.4% driving continued improvement in operating leverage Deposits per branch improved to $63.6 million from $43.6 million on a year over year basis Represents a non-GAAP financial measure. See “Non-GAAP Reconciliation” in the appendix.

Loan and Lease Trends Loan & Lease Portfolio December 31, 2017 December 31, 2018 ($ in millions) Originated and Acquired Loan & Lease Portfolio Total loans and leases were $3.5 billion at 4Q18, an increase of $45.8 million or 1.3% from the prior quarter and 53.7% from 4Q17 Originated portfolio increased by $171.6 million or 33.0% annualized Acquired portfolio decreased by $125.8 million Payoff activity increased by $12.2 million versus 3Q18 $110.7 million in 4Q18 compared to $98.5 million in 3Q18

Total deposits increased $9.1 million to $3.7 billion Growth in non-interest bearing deposits and jumbo CDs offset by declines in other deposit categories Total deposit costs increased to 75 bps from 64 bps in the prior quarter Cost of interest bearing deposits increased by 14 bps and slowed relative to previous two quarters Deposit Trends Average Non-Interest Bearing Deposits ($ in millions) Deposit Composition Cost of Interest Bearing Deposits

Net Interest Income and Net Interest Margin Trends Net interest income increased $668,000 to $53.3 million, primarily due to higher average balances of loans and leases and the rising interest rate environment Net interest margin decreased four basis points to 4.69% from 3Q18 due to 18 bps decline in accretion income Net interest margin (excluding accretion income)1 increased 14 basis points to 4.13%, primarily due to higher average loan yields Earning asset yields increased to 5.54%, up five bps from 3Q18 Net Interest Margin Net Interest Income Represents a non-GAAP financial measure. See “Non-GAAP Reconciliation” in the appendix. ($ in millions) (1)

Total Non-Interest Income Non-Interest Income Trends Non interest income increased $3.4 million from 3Q18 Higher net gains on sales of loans $2.9 million impairment charge to servicing asset due to higher prepayment speeds and a rising interest rate environment Other fee income line items remained stable for the quarter ($ in millions) Total SBC Closed Loan Commitments Net Gains on Sales of Loans $141.1 million in closed loan commitments in 4Q18, compared to $136.1 million in 3Q18 $87.4 million of loan sales in 4Q18, compared to $59.6 million in 3Q18 Average premium increased due to more favorable mix of loans sold Small Business Capital

Non-Interest Expense Trends Non-interest expenses were stable for the quarter Non-interest expense, excluding significant adjustment items(1), was $39.1 million, an increase 4.4% from 3Q18 Salary and employee benefit expenses stabilized during the quarter Higher loan and lease related expenses, professional fees, and occupancy Adjusted efficiency ratio(1) of 54.95%, an improvement from 55.78% in prior quarter and 63.23% in 4Q17 ($ in millions) Efficiency Ratio Non-Interest Expense Represents a non-GAAP financial measure. See “Non-GAAP Reconciliation” in the appendix. (1) (1)

Asset Quality Trends Non performing assets improved to 0.67% in 4Q18 compared to 0.71% in 3Q18 NPLs/ Total Loans & Leases decreased to 0.79% in 4Q18 from 0.87% in 3Q18, primarily due to decline in government guaranteed portions of NPLs NPLs/ Total Loans & Leases excluding government guaranteed portions stable at 0.66% Other real estate owned increased by $423,000 during the quarter Provision expense of $3.9 million decreased from $5.8 million in 3Q18, primarily due to a reduction in specific impairment in the unguaranteed portion of the government guaranteed portfolio NCOs declined to 0.24% of average loans and leases from 0.25% in 3Q18 ALLL/Loans and Leases increased to 0.72% in 4Q18 compared to 0.68% in 3Q18 Acquisition accounting adjustments on acquired loans stood at $34.0 million versus $42.4 in the prior quarter NPLs / Total Loans & Leases ALLL / Loans & Leases

2019 Outlook and Strategic Priorities Acquisition Updates Areas of Focus Systems conversion on track for completion during first quarter of 2019 All regulatory approvals received for Oak Park River Forest (OPRF) Opportunities to partner with OPRF team to gain share in Oak Park and River Forest markets Continue to analyze acquisition opportunities in our markets Focus on core deposit growth in targeted markets Capitalize on disruption in Chicago banking market by adding new customers and banking talent Continue to pursue disciplined loan growth opportunities Continue to enhance product capabilities post conversion Improved Profitability Fully realizing the synergies from First Evanston and OPRF acquisitions Disciplined expense management to drive additional operating leverage Continuing to evaluate and optimize the branch network Increase fees generated by growth in Wealth Management / Trust, and Treasury Management

Appendix

Five Quarter Financial Summary ($ in millions, except per share data) Represents a non-GAAP financial measure. See “Non-GAAP Reconciliation” in the appendix. For the Three Months Ended, December 31, 2018 September 30, 2018 June 30, 2018 March 31, 2018 December 31, 2017 Income Statement Net interest income $53.3 $52.6 $39.1 $33.7 $32.2 Provision 3.9 5.8 4.0 5.1 3.3 Non-interest income 14.6 11.1 14.5 11.4 12.6 Non-interest expense 40.4 38.0 45.8 31.9 30.4 Pretax income 23.6 19.9 3.8 8.1 11.1 Income taxes 6.4 5.4 1.1 1.3 11.9 Net income 17.1 14.5 2.8 6.8 (0.8) Dividends on preferred shares 0.2 0.2 0.2 0.2 0.2 Net income (loss) available attributable to common shareholders $16.9 $14.3 $2.6 $6.6 ($1.0) Diluted earnings (loss) per common share(1) $0.46 $0.39 $0.08 $0.22 ($0.03) Balance Sheet Total loans and leases $3,501.6 $3,455.8 $3,348.7 $2,280.4 $2,277.5 Total deposits 3,749.9 3,740.8 3,644.9 2,524.5 2,443.3 Tangible common equity(1) 479.3 456.6 441.3 381.9 376.8             Balance Sheet Metrics Loans and leases / deposits 93.91% 92.62% 92.03% 90.66% 93.43% Tangible common equity / tangible assets(1) 10.02 9.60 9.51 11.26 11.51 Key Performance Ratios Net interest margin 4.69% 4.73% 4.43% 4.45% 4.26% Efficiency ratio 56.81 56.57 83.35 69.04 66.06 Adjusted efficiency ratio(1) 54.95 55.78 63.48 68.77 63.23 Non-interest expense to average assets 3.27 3.13 4.75 3.85 3.64 Non-interest income to total revenues(1) 21.48 17.48 27.08 25.33 28.22 Return on average assets 1.39 1.20 0.29 0.82 (0.09) Adjusted return on average assets(1) 1.47 1.23 1.10 0.74 0.87 Tangible book value per share(1) $13.19 $12.59 $12.18 $12.99 $12.85 Byline Bancorp, inc. tm (1) Represents a non-GAAP financial measure. See “Non-GAAP Reconciliation” in the appendix.

Non-GAAP Reconciliation Byline Bancorp, inc. tm As of or For the Three Months Ended December 31, 2018 September 30, 2018 June 30, 2018 March 31, 2018 December 31, 2017 (dollars in thousands, except per share data) Net income (loss) and earnings per share excluding significant items Reported Net Income (Loss) $17,121 $14,536 $2,768 $6,768 $(766) Significant items: Incremental income tax benefit of state tax rate change — — — — — Incremental income tax (benefit) expense attributed to federal income tax reform — — — (724) 7,154 Impairment charges on assets held for sale 372 139 117 — — Merger-related expense 266 150 1,517 123 1,272 Core system conversion expense 625 213 9,009 — — Tax benefit on significant items (297) (112) (2,832) (34) (395) Adjusted Net Income $18,087 $14,926 $10,579 $6,133 $7,265 Reported Diluted Earnings (Loss) per Share $0.46 $0.39 $0.08 $0.22 $(0.03) Significant items: Incremental income tax benefit of state tax rate change — — — — — Incremental income tax (benefit) expense attributed to federal income tax reform — — — (0.02) 0.24 Impairment charges on assets held for sale 0.01 — — — — Merger-related expense 0.01 — 0.05 0.01 0.04 Core system conversion expense 0.02 0.01 0.28 — — Tax benefit on significant items (0.01) — (0.09) — (0.01) Adjusted Diluted Earnings (Loss) per Share $0.49 $0.40 $0.32 $0.21 $0.24

Non-GAAP Reconciliation (continued) Byline Bancorp, inc. tm As of or For the Three Months Ended As of or For the Year Ended December 31, 2018 September 30, 2018 June 30, 2018 March 31, 2018 December 31, 2017 December 31, 2018 December 31, 2017 (dollars in thousands, except share and per share data)(ratios annualized, where applicable) Adjusted non-interest expense: Non-interest expense $40,364 $37,956 $45,770 $31,919 $30,358 $156,009 $119,523 Less: significant items Impairment charges on assets held for sale 372 139 117 — — 628 951 Merger-related expense 266 150 1517 123 1,272 2,056 1,272 Core system conversion expense 625 213 9,009 — — 9,847 — Adjusted non-interest expense $39,101 $37,454 $35,127 $31,796 $29,086 $143,478 $117,300 Adjusted non-interest expense excluding amortization of intangible assets: Adjusted non-interest expense $39,101 $37,454 $35,127 $31,796 $29,086 $143,478 $117,300 Less: Amortization of intangible assets 1,834 1,898 1,130 767 767 5,629 3,074 Adjusted non-interest expense excluding amortization of intangible assets 37,267 35,556 33,997 31,029 28,319 137,849 114,226 Pre-tax pre-provision net income: Pre-tax income $23,581 $19,938 $3,832 $8,089 $11,085 $55,440 $40,794 Add: Provision for loan and lease losses 3,882 5,842 3,956 5,115 3,347 18,795 12,653 Pre-tax pre-provision net income $27,463 $25,780 $7,788 $13,204 $14,432 $74,235 $53,447 Adjusted pre-tax pre-provision net income: Pre-tax pre-provision net income $27,463 $25,780 $7,788 $13,204 $14,432 $74,235 $53,447 Impairment charges on assets held for sale 372 139 117 — — 628 951 Merger-related expense 266 150 1,517 123 1,272 2,056 1,272 Core system conversion expense 625 213 9,009 — — 9,847 — Adjusted pre-tax pre-provision net income $28,726 $26,282 $18,431 $13,327 $15,704 $86,766 $55,670 Total revenues: Net interest income $53,261 $52,593 $39,056 $33,695 $32,151 $178,605 $122,912 Add: non-interest income 14,566 11,143 14,502 11,428 12,639 51,639 50,058 Total revenues $67,827 $63,736 $53,558 $45,123 $44,790 $230,244 $172,970 Tangible common stockholders' equity: Total stockholders' equity $650,672 $629,861 $616,406 $462,936 $458,578 $650,672 $458,578 Less: Preferred stock 10,438 10,438 10,438 10,438 10,438 10,438 10,438 Less: Goodwill 127,536 127,536 127,536 54,562 54,562 127,536 54,562 Less: Core deposit intangibles and other intangibles 33,419 35,248 37,139 15,991 16,756 33,419 16,756 Tangible common stockholders' equity $479,279 $456,639 $441,293 $381,945 $376,822 $479,279 $376,822

Non-GAAP Reconciliation (continued) Byline Bancorp, inc. tm As of or For the Three Months Ended As of or For the Year Ended December 31, 2018 September 30, 2018 June 30, 2018 March 31, 2018 December 31, 2017 December 31, 2018 December 31, 2017 (dollars in thousands, except share and per share data)(ratios annualized, where applicable) Tangible assets: Total assets $4,942,574 $4,917,409 $4,805,280 $3,462,372 $3,366,130 $4,942,574 $3,366,130 Less: Goodwill 127,536 127,536 127,536 54,562 54,562 127,536 54,562 Less: Core deposit intangibles and other intangibles 33,419 35,248 37,139 15,991 16,756 33,419 16,756 Tangible assets $4,781,619 $4,754,625 $4,640,605 $3,391,819 $3,294,812 $4,781,619 $3,294,812 Average tangible common stockholders' equity: Average total stockholders' equity $639,885 $625,621 $518,547 $459,535 $463,301 $561,568 $427,339 Less: Average preferred stock 10,438 10,438 10,438 10,438 10,438 10,438 17,837 Less: Average goodwill 127,536 127,536 78,619 54,562 52,003 97,347 51,975 Less: Average core deposit intangibles and other intangibles 34,564 36,444 22,998 16,417 17,186 27,679 18,360 Average tangible common stockholders' equity $467,347 $451,203 $406,492 $378,118 $383,674 $426,104 $339,167 Average tangible assets: Average total assets $4,896,434 $4,809,939 $3,863,184 $3,362,071 $3,303,673 $4,238,602 $3,302,231 Less: Average goodwill 127,536 127,536 78,619 54,562 52,003 97,347 51,975 Less: Average core deposit intangibles and other intangibles 34,564 36,444 22,998 16,417 17,186 27,679 18,360 Average tangible assets $4,734,334 $4,645,959 $3,761,567 $3,291,092 $3,234,484 $4,113,576 $3,231,896 Tangible net income available (loss attributable) to common stockholders: Net income available (loss attributable) to common stockholders $16,925 $14,340 $2,570 $6,575 $(962) $40,410 $10,418 Add: After-tax intangible asset amortization 1,322 1,370 815 553 455 4,061 1,825 Tangible net income available (loss attributable) to common stockholders $18,247 $15,710 $3,385 $7,128 $(507) $44,471 $12,243 Adjusted Tangible net income available (loss attributable) to common stockholders: Tangible net income available (loss attributable) to common stockholders $18,247 $15,710 $3,385 $7,128 $(507) $44,471 $12,243 Incremental income tax benefit of state tax rate change — — — — — — (4,790) Incremental income tax (benefit) expense attributed to federal income tax reform — — — (724) 7,154 (724) 7,154 Impairment charges on assets held for sale 372 139 117 — — 628 951 Merger-related expense 266 150 1,517 123 1,272 2,056 1,272 Core system conversion expense 625 213 9,009 — — 9,847 — Tax benefit on significant items (297) (112) (2,832) (34) (395) (3,275) (781) Adjusted tangible net income available (loss attributable) to common stockholders $19,213 $16,100 $11,196 $6,493 $7,524 $53,003 $16,049

Non-GAAP Reconciliation (continued) Byline Bancorp, inc. tm As of or For the Three Months Ended As of or For the Year Ended December 31, 2018 September 30, 2018 June 30, 2018 March 31, 2018 December 31, 2017 December 31, 2018 December 31, 2017 (dollars in thousands, except share and per share data)(ratios annualized, where applicable) Net interest margin: Reported net interest margin 4.69% 4.73% 4.43% 4.45% 4.26% 4.60% 4.11% Effect of accretion income on acquired loans (0.56)% (0.74)% (0.41)% (0.31)% (0.30)% (0.53)% (0.29)% Net interest margin excluding accretion 4.13% 3.99% 4.02% 4.14% 3.96% 4.07% 3.82% Pre-tax pre-provision return on average assets: Pre-tax pre-provision net income $27,463 $25,780 $7,788 $13,204 $14,432 $74,235 $53,447 Total average assets 4,896,434 4,809,939 3,863,184 3,362,071 3,303,673 4,238,602 3,302,231 Pre-tax pre-provision return on average assets 2.23% 2.13% 0.81% 1.59% 1.73% 1.75% 1.62% Adjusted Pre-tax pre-provision return on average assets: Adjusted pre-tax pre-provision net income $28,726 $26,282 $18,431 $13,327 $15,704 $86,766 $55,670 Total average assets 4,896,434 4,809,939 3,863,184 3,362,071 3,303,673 4,238,602 3,302,231 Adjusted pre-tax pre-provision return on average assets 2.33% 2.17% 1.91% 1.61% 1.89% 2.05% 1.69% Non-interest income to total revenues: Non-interest income $14,566 $11,143 $14,502 $11,428 $12,639 $51,639 $50,058 Total revenues 67,827 63,736 53,558 45,123 44,790 230,244 172,970 Non-interest income to total revenues 21.48% 17.48% 27.08% 25.33% 28.22% 22.43% 28.94% Adjusted non-interest expense to average assets: Adjusted non-interest expense $39,101 $37,454 $35,127 $31,796 $29,086 $143,478 $117,300 Total average assets 4,896,434 4,809,939 3,863,184 3,362,071 3,303,673 4,238,602 3,302,231 Adjusted non-interest expense to average assets 3.17% 3.09% 3.65% 3.84% 3.49% 3.39% 3.55% Adjusted efficiency ratio: Adjusted non-interest expense excluding amortization of intangible assets $37,267 $35,556 $33,997 $31,029 $28,319 $137,849 $114,226 Total revenues 67,827 63,736 53,558 45,123 44,790 230,244 172,970 Adjusted efficiency ratio 54.95% 55.78% 63.48% 68.77% 63.23% 59.87% 66.04%

Non-GAAP Reconciliation (continued) Byline Bancorp, inc. tm As of or For the Three Months Ended As of or For the Year Ended December 31, 2018 September 30, 2018 June 30, 2018 March 31, 2018 December 31, 2017 December 31, 2018 December 31, 2017 (dollars in thousands, except share and per share data)(ratios annualized, where applicable) Adjusted return on average assets: Adjusted net income 18,087 14,926 10,579 6,133 7,265 49,725 25,501 Total average assets $4,896,434 $4,809,939 $3,863,184 $3,362,071 $3,303,673 $4,238,602 $3,302,231 Adjusted return on average assets 1.47% 1.23% 1.10% 0.74% 0.87% 1.17% 0.77% Adjusted return on average stockholders' equity: Adjusted net income $18,087 $14,926 $10,579 $6,133 $7,265 $49,725 $25,501 Average stockholders' equity 639,885 625,621 518,547 459,535 463,301 561,568 427,339 Adjusted return on average stockholders' equity 11.21% 9.47% 8.18% 5.41% 6.22% 8.85% 5.97% Tangible common equity to tangible assets: Tangible common equity $479,279 $456,639 $441,293 $381,945 $376,822 $479,279 $376,822 Tangible assets 4,781,619 4,754,625 4,640,605 3,391,819 3,294,812 4,781,619 3,294,812 Tangible common equity to tangible assets 10.02% 9.60% 9.51% 11.26% 11.51% 10.02% 11.51% Return on average tangible common stockholders' equity: Tangible net income available (loss attributable) to common stockholders $18,247 $15,710 $3,385 $7,128 $(507) $44,471 $12,243 Average tangible common stockholders' equity 467,347 451,203 406,492 378,118 383,674 426,104 339,167 Return on average tangible common stockholders' equity: 15.49% 13.81% 3.34% 7.65% (0.52)% 10.44% 3.61% Adjusted return on average tangible common stockholders' equity: Adjusted tangible net income available (loss attributable) to common stockholders $19,213 $16,100 $11,196 $6,493 $7,524 $53,003 $16,049 Average tangible common stockholders' equity 467,347 451,203 406,492 378,118 383,674 426,104 339,167 Adjusted return on average tangible common stockholders' equity 16.31% 14.16% 11.05% 6.96% 7.78% 12.44% 4.73% Tangible book value per share: Tangible common equity $479,279 $456,639 $441,293 $381,945 $376,822 $479,279 $376,822 Shares of common stock outstanding 36,343,239 36,279,600 36,218,955 29,404,048 29,317,298 36,343,239 29,317,298 Tangible book value per share $13.19 $12.59 $12.18 $12.99 $12.85 $13.19 $12.85