BYLINE BANCORP, INC. Stock Compensation Disclosure

Note 18—Share-Based Compensation

In June 2017, the Company's Board of Directors adopted, and the Company's stockholder approved, the 2017 Omnibus Incentive Compensation Plan (the "Omnibus Plan"). The Omnibus Plan provides for the grant of stock options, stock appreciation rights, restricted stock, restricted stock units, dividend equivalent rights and other equity-based, equity-related or cash-based awards. A total of 2,600,000 shares of our common stock have been reserved for issuance under the Omnibus Plan. As of December 31, 2025, there were 483,586 shares available for future grants under the Omnibus Plan.

The Company primarily grants time-based restricted share awards that vest over a one to four year period, subject to continued employment. The Company also grants performance-based restricted share awards. The number of shares which may be earned under the award is dependent upon the Company’s return on average assets, weighted equally over a three-year period, measured against a peer group consisting of publicly-traded bank holding companies. The value associated with the grant of restricted stock awards is determined by multiplying the fair market value of the Company's common stock on the grant date by the number of shares awarded.

During 2025, the Company granted 329,702 shares of restricted common stock, par value $0.01 per share. Of this total, 243,818 restricted shares will vest ratably over three years on each anniversary of the grant date, 6,678 restricted shares will cliff vest on the third anniversary of the grant date, and 10,240 restricted shares will vest on the first anniversary of the grant date, all subject to continued employment. In addition, 68,966 performance-based restricted shares were included in the 2025 grant. The number of performance-based shares which may be earned under the award is dependent upon the Company’s total stockholder return and return on average assets, weighted equally, over a three-year period ending December 31, 2027, measured against the KBW Regional Bank Index. Results will be measured cumulatively at the end of the three years, and any earned shares will vest on the third anniversary of the grant date.

A total of 336,592, 244,548, and 238,638 restricted shares vested during the years ended December 31, 2025, 2024, and 2023, respectively. The fair value of restricted shares that vested during the years ended December 31, 2025, 2024, and 2023 were $9.6 million, $5.2 million and $5.7 million, respectively.

The Company recognizes share-based compensation based on the estimated fair value of the restricted stock at the grant date. Share-based compensation expense is included in non-interest expense in the Consolidated Statements of Operations. The fair value of the total stockholder return performance-based awards granted in 2025 and 2024 were calculated based on a Monte Carlo simulation, using the following assumptions:

Note 18—Share-Based Compensation (continued)

The fair value of the unvested restricted stock awards at December 31, 2025 was $21.7 million.

In October 2014, the Company adopted the Byline Bancorp, Inc. Equity Incentive Plan ("BYB Plan"). The maximum number of shares available for grants under this plan was 2,476,122 shares. The Company granted 1,846,968 options to purchase shares under this plan. In June 2017, the Board of Directors terminated the BYB Plan and no future grants can be made under this plan. No options to purchase shares remain outstanding under the BYB Plan as of December 31, 2025.

The types of stock options granted under the BYB Plan were Time Options and Performance Options. The exercise price of each option was equal to the fair value of the stock as of the date of grant. These option awards had vesting periods ranging from one to five years and had 10-year contractual terms. Stock volatility was computed as the average of the volatilities of peer group companies.

The fair values of the stock options were determined using the Black-Scholes-Merton model for Time Options and a Monte Carlo simulation model for Performance Options.

Under the BYB plan, there were 334,423 and 434,141 stock options exercised during the year ended December 31, 2025, and 2024, respectively. No stock options were exercised during the year ended December 31, 2023. Proceeds from the exercise of stock options were $334,000 and $2.6 million with a related tax benefit of $1.3 million and $1.6 million, for the years ended December 31, 2025 and 2024, respectively. No stock options vested during the years ended December 31, 2025 or 2024, respectively. No stock option compensation expense was recognized for the years ended December 31, 2025, 2024, and 2023.

Pursuant to the terms of the Agreement and Plan of Merger with First Evanston and its subsidiaries, dated as of November 27, 2017 (the "First Evanston Merger Agreement"), each outstanding First Evanston option held by a participant in the First Evanston Bancorp, Inc. Stock Incentive Plan (the "FEB Plan") ceased to represent a right to acquire shares of First Evanston common stock and was assumed and converted automatically into a fully vested and exercisable adjusted option to purchase shares of Byline common stock (each an "Adjusted Option"). In accordance with the First Evanston Merger Agreement, the number of shares of Byline common stock to which each such Adjusted Option relates is equal to the product (rounded down to the nearest whole share of Byline common stock) of: (a) the number of shares of First Evanston common stock subject to the First Evanston option immediately prior to May 31, 2018, multiplied by (b) 4.725. Each Adjusted Option has an exercise price per share of Byline common stock equal to the quotient (rounded up to the nearest whole cent) of (x) the per share exercise price of such First Evanston option immediately prior to May 31, 2018, divided by (y) 4.725. The description of the conversion process is based on, and qualified by, the First Evanston Merger Agreement.

Note 18—Share-Based Compensation (continued)

Under the FEB plan, a total of 18,330, 57,686, and 59,153 stock options were exercised during the years ended December 31, 2025, 2024, and 2023, respectively. Proceeds from the exercise of stock options were $214,000, $675,000 and $659,000 with a related tax benefit of $83,000, $252,000 and $158,000, for the years ended December 31, 2025, 2024, and 2023, respectively.