BYLINE BANCORP, INC.

Note 1—Basis of Present ation

These unaudited interim condensed consolidated financial statements include the accounts of Byline Bancorp, Inc., a Delaware corporation (the "Company," "Byline," "we," "us," "our"), a bank holding company whose principal activity is the ownership and management of its Illinois state chartered subsidiary bank, Byline Bank (the "Bank"), based in Chicago, Illinois.

These unaudited interim condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP") for interim financial information and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X as promulgated by the Securities and Exchange Commission ("SEC"). In preparing these financial statements, the Company has evaluated events and transactions subsequent to June 30, 2025 for potential recognition or disclosure. In the opinion of management, all adjustments (consisting of normal recurring accruals) considered necessary for a fair presentation of the financial position and results of operations for the periods presented have been included. Certain information in footnote disclosures normally included in financial statements prepared in accordance with GAAP has been condensed or omitted pursuant to the rules and regulations of the SEC and the accounting standards for interim financial statements. These financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Company’s Consolidated Financial Statements as of December 31, 2024 and 2023.

The Company hasone reportable segment. The Company’s chief operating decision makers evaluate the operations of the Company using consolidated information for purposes of allocating resources and assessing performance. Refer to Note 21—Segment Information for additional disclosures.

In accordance with the Financial Accounting Standards Board ("FASB") Accounting Standards Codification ("ASC") Topic 855, "Subsequent Events," the Company’s management has evaluated subsequent events for potential recognition or disclosure through the date of the issuance of these Condensed Consolidated financial statements.

On August 7, 2025, the Company issued $75.0 million in 6.875% fixed-to-floating rate subordinated notes that mature on August 15, 2035. Refer to Note 13—Subordinated Notes and Junior Subordinated Debentures for additional discussion.

No other subsequent events were identified that would have required a change to the condensed consolidated financial statements or disclosure in the notes to the condensed consolidated financial statements.

Note 2—Accounting Pronouncements Recently Adopted or Issued

The following reflect recent accounting pronouncements that have been adopted or are pending adoption by the Company.

Adopted Accounting Pronouncements

Income Taxes – Improvements to Income Tax Disclosures (Topic 740) –In December 2023, the FASB issued ASU 2023-09 to provide additional transparency into an entity’s income tax disclosures primarily related to the rate reconciliation and income taxes paid information. The standard requires that public business entities disclose, on an annual basis, specific categories in the rate reconciliation and additional information for reconciling items meeting a certain quantitative threshold. The amendments also require that entities disclose on an annual basis: 1) income taxes paid (net of refunds received) disaggregated by federal (national), state, and foreign taxes and 2) the income taxes paid (net of refunds received) disaggregated by individual jurisdictions exceeding 5% of total income taxes paid (net of refunds received). The amendments are effective for public business entities for annual periods beginning after December 15, 2024. The Company has evaluated the disclosure requirements of this update and has concluded it will only impact certain limited annual disclosures with no material impact to the consolidated financial statements.

Issued Accounting Pronouncements Pending Adoption

Income Statement (Topic 220) – In November 2024, the FASB issued ASU 2024-03, Income Statement (Topic 220) – Reporting Comprehensive Income –Expense Disaggregation Disclosures, to address requests from investors for more detailed information about certain expense types. The standard requires that public business entities disclose disaggregated information about specific relevant natural expense categories underlying certain income statement expense line items. The ASU requires entities to disaggregate relevant expense caption presented on the face of the income statement within continuing operations into expense categories such as employee compensation, depreciation, and intangible asset amortization. The amendments are effective for public business entities for annual periods beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027. Entities are required to adopt prospectively. In January 2025, the FASB issued ASU 2025-01 to amend the effective date of ASU 2024-03 to clarify that all public business entities are required to adopt the guidance in annual reporting periods beginning after December 15, 2026, and interim periods within annual reporting periods beginning after December 15, 2027. The Company is evaluating the accounting and disclosure requirements of this update and does not expect them to have a material effect on the consolidated financial statements.

Note 3—Acquisition of a Business

On April 1, 2025 we acquired all of the outstanding common stock of First Security Bancorp, Inc., a Delaware corporation ("First Security"), and its wholly owned subsidiary, First Security Trust and Savings Bank pursuant to an Agreement and Plan of Merger, dated September 30, 2024 (the "First Security acquisition"). As a result of the acquisition, effective April 1, 2025, First Security Trust and Savings Bank was merged with and into Byline Bank.

At the effective time of the merger, each share of First Security's common stock was converted into the right to receive 2.3539 shares of Byline common stock. The value of the total merger consideration at closing was approximately $41.5 million.

The transaction resulted in goodwill of $147,000, which is nondeductible for tax purposes, as this acquisition was a nontaxable transaction. Goodwill represents the premium paid over the fair value of the net tangible and intangible assets acquired and reflects related synergies expected from the combined operations.

Merger-related expenses, including salaries and employee benefits of $3.5 million, acquisition advisory expenses of $597,000, core system conversion expenses of $251,000, and other non-interest expenses of $78,000 related to the acquisition are reflected in non-interest expense on the Condensed Consolidated Statements of Operations for thethree months ended June 30, 2025.

Merger-related expenses, including salaries and employee benefits of $3.5 million, acquisition advisory expenses of $788,000, core system conversion expenses of $696,000, and other non-interest expenses of $78,000 related to the acquisition are reflected in non-interest expense on the Condensed Consolidated Statements of Operations for thesix months ended June 30, 2025.

There wereno merger-related expenses in the three and six months ended June 30, 2024.

The acquisition was accounted for using the acquisition method of accounting in accordance with ASC Topic 805. Assets acquired, liabilities assumed, and consideration exchanged were recorded at their respective acquisition date fair values. Determining the fair value of assets and liabilities involves significant judgment regarding methods and assumptions used to calculate estimated fair values. All of the fair values are preliminary and subject to refinement for up to one year after the closing date of the acquisition as additional information regarding the closing date fair values become available.

The following table presents a summary of the preliminary estimates of the fair values of assets acquired and liabilities assumed as of the acquisition date:

The following table presents the fair value and gross contractual amounts receivable of acquired non-credit-deteriorated loans from the acquisition, and their respective expected contractual cash flows as of the acquisition date:

(1)Includes interest payments not expected to be collected due to loan prepayments as well as principal and interest payments not expected to be collected due to customer default.

The following table provides the unaudited pro forma information for the results of operations for thethree and six months ended June 30, 2024 and for the six months ended June 30, 2025, as if the acquisition had occurred on January 1, 2024. The pro forma results combine the historical results of First Security into the Company’s Consolidated Statements of Operations, including the impact of certain acquisition accounting adjustments, which includes loan discount accretion, intangible assets amortization, and deposit premium accretion. The pro forma results have been prepared for comparative purposes only and are not necessarily indicative of the results that would have been obtained had the acquisition actually occurred on January 1, 2024. No assumptions have been applied to the pro forma results of operations regarding possible revenue enhancements, provision for credit losses, expense efficiencies or asset dispositions. Recognized acquisition-related expenses and other adjustments related to the timing of expenses, are included in net income in the following table:

Theoperating results of the Company include the operating results generated by the acquired assets and assumed liabilities of First Security for the period from April 1, 2025 through June 30, 2025. Revenues and earnings of the acquired company since the acquisition date have not been disclosed as it is not practicable as First Security was merged into the Company and separate financial information is not readily available.

Note 4—Securities

The following tables summarize the amortized cost and fair values of securities available-for-sale and securities held-to-maturity as of the dates shown and the corresponding amounts of gross unrealized gains and losses:

(1)Basis adjustments represent the amount of fair value hedging adjustments included in the carrying amounts of fixed-rate investment securities designated in fair value hedging arrangements. Refer to Note 16—Derivative Instruments and Hedge Activities for additional discussion.

There wereno securities classified as held-to-maturity as of June 30, 2025. The Company did not classify securities as trading during the three and six months ended June 30, 2025 or during 2024.

The Company hedges the fair value of certain fixed-rate investment securities.

Gross unrealized losses and fair values, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of the dates presented, are summarized as follows:

Certain securities have fair values less than amortized cost and, therefore, contain unrealized losses. The Company evaluated the securities which had unrealized losses for potential credit losses and determined there were none. There were 298 securities available-for-sale with unrealized losses at June 30, 2025. There wasno allowance for credit losses for held-to-maturity debt securities at December 31, 2024. The evaluation for potential credit losses is based upon factors such as the creditworthiness of the issuers/guarantors, the underlying collateral, if applicable, and the continuing payment performance of the securities.

Accrued interest receivable on securities totaled$5.4 million at June 30, 2025 and$4.9 million at December 31, 2024, respectively, and are included in accrued interest receivable and other assets line item in the Condensed Consolidated Statement of Financial Condition. The amounts are excluded from the estimate of credit losses.

The Company anticipates full recovery of amortized cost with respect to these securities by maturity. The Company does not intend to sell these securities and it is not more likely than not that the Company will be required to sell them before recovery of their amortized cost basis, which may be at maturity.

The proceeds from all sales and calls of securities available-for-sale, and the associated gains and losses were as follows for the periods presented:

Securities posted and pledged as collateral for the following purpose or beneficiary as of the following dates:

At June 30, 2025 and December 31, 2024, there were no holdings of securities of any one issuer, other than the U.S. Government and its agencies, in an amount greater than 10% of stockholders’ equity.

At June 30, 2025, the amortized cost and fair value of debt securities are shown by contractual maturity. Expected maturities may differ from contractual maturities if borrowers have the right to call or prepay obligations with or without call or prepayment penalties. Securities not due at a single maturity date are shown separately.

Note 5—Loan and Lease Receivables and Allowance for Credit Losses

Loan and Lease Receivables

Outstanding loan and lease receivables as of the dates presented were categorized as follows:

Total loans and leases consist of originated loans and leases, purchased credit deteriorated ("PCD") and acquired non-credit-deteriorated loans and leases. Fair value adjustments for acquired loans are included in total loans and leases. At June 30, 2025 and December 31, 2024, total loans and leases included the guaranteed amount of U.S. government guaranteed loans of$105.5 million and$97.6 million, respectively. At June 30, 2025 and December 31, 2024, the discount on the unguaranteed portion of U.S. government guaranteed loans was $25.6 million for both periods, which is included in total loans and leases. At June 30, 2025 and December 31, 2024, commercial and industrial loans included overdraft deposits of $1.1 million and $1.0 million, respectively, which were reclassified as loans. At June 30, 2025 and December 31, 2024, loans and leases and loans held for sale pledged as security for borrowings were $1.9 billion and $2.0 billion, respectively. Accrued interest on loans and leases was $35.5 million and $35.2 million at June 30, 2025 and December 31, 2024, respectively, and is included in the accrued interest receivable and other assets line item on the Condensed Consolidated Statement of Financial Condition.

The minimum annual lease payments for lease financing receivables as of June 30, 2025 are summarized as follows:

Originated loans and leases represent originations excluding loans initially acquired in a business combination. However, once an acquired loan reaches its maturity date, and is re-underwritten and renewed, it is internally classified as an originated loan. PCD loans are those acquired from a business combination with evidence of credit quality deterioration and are accounted for under ASC Topic 326. Acquired non-credit-deteriorated loans and leases represent loans and leases acquired with an outstanding balance from a business combination without more than insignificant evidence of credit quality deteriorationand are accounted for under ASC Topic 310-20. The following tables summarize the balances for each respective loan and lease category as of the dates presented:

PCD loans—The unpaid principal balance and carrying amount of PCD loans excluding an allowance for credit losses - loans and leases of $4.4 million and $4.2 million as of the dates presented:

The following table is a reconciliation of acquired First Security PCD loans between their purchase price and their par value at the time of the acquisition. Refer to Note 3—Acquisition of a Business for further information.

Acquired non-credit-deteriorated loans and leases—The unpaid principal balance and carrying value for acquired non-credit deteriorated loans and leases, excluding an allowance for credit losses of $4.0 million and $3.4 million at June 30, 2025 and December 31, 2024, respectively, were as follows for the dates presented:

The Company hedges interest rates on certain loans using interest rate swaps through which the Company pays variable amounts and receives fixed amounts. Refer to Note 16—Derivative Instruments and Hedge Activities for additional discussion.

Allowance for Credit Losses

Loans and leases considered for inclusion in the allowance for credit losses include acquired non-credit-deteriorated loans and leases, purchased credit deteriorated loans, and originated loans and leases.

The Bank’s credit risk rating methodology assigns risk ratings from 1 to 10, where a higher rating represents higher risk. Risk ratings for all loans of $1.0 million or more are reviewed annually. The risk rating categories are described by the following groupings:

Pass—Ratings 1‑4 define the risk levels of borrowers and guarantors that offer a minimal to an acceptable level of risk.

Watch—A watch asset (rating of 5) has credit exposure that presents higher than average risk and warrants greater than routine attention by Bank personnel due to conditions affecting the borrower, the borrower’s industry or the economic environment.

Special Mention—A special mention asset (rating of 6) has potential weaknesses that deserve management’s close attention. If left uncorrected, these potential weaknesses may result in deterioration of the repayment prospects for the asset or in the Company’s credit position at some future date.

Substandard Accrual—A substandard accrual asset (rating of 7) has well‑defined weakness or weaknesses in cash flow and collateral coverage resulting in a distinct possibility that the Company will sustain some loss if the deficiencies are not corrected. This classification may be used in limited cases, where despite credit severity, the borrower is current on payments and there is an agreed plan for credit remediation.

Substandard Non‑Accrual—A substandard asset (rating of 8) has well‑defined weakness or weaknesses in cash flow and collateral coverage resulting in the distinct possibility that the Company will sustain some loss if the deficiencies are not corrected.

Doubtful—A doubtful asset (rating of 9) has all the weaknesses inherent in one classified substandard with the added characteristic that the weaknesses make collection or liquidation in full, on the basis of currently existing facts, conditions and values, highly questionable and improbable.

Loss—A loss asset (rating of 10) is considered uncollectible and of such little value that its continuance as a realizable asset is not warranted.

Revolving loans that are converted to term loans are treated as new originations and are presented by year of origination. Generally, existing term loans that are re-underwritten are reflected in the table in the year of renewal. During the six months ended June 30, 2025, there were $22.0 million of revolving loans that were converted to term loans. During the year ended December 31, 2024, $67.3 million of revolving loans that were converted to term loans.

The following tables summarize the risk rating categories of the loans and leases considered for inclusion in theallowance for credit losses - loans and leases calculation, as of the dates presented, and includes the gross charge-offs for the six months ended June 30, 2025 and year ended December 31, 2024:

At June 30, 2025 and at December 31, 2024, there were no loans or leases which were risk rated Doubtful or Loss.

The following tables summarize contractual delinquency information of the loans and leases considered for inclusion in theallowance for credit losses - loans and leases calculation as of the dates presented:

Total non-accrual loans without an allowance included $10.1 million of commercial real estate loans, $790,000 of residential real estate, and $10.9 million of commercial and industrial loans as of June 30, 2025. The Company recog nized $899,000 and $1.9 million of interest income on non-accrual loans and leases for thethree and six months ended June 30, 2025, respectively.

Total non-accrual loans without an allo wance included $6.0 million of commercial real estate loans, $790,000 of residential real estate loans, and $3.8 million of commercial and industrial loans, as of December 31, 2024. The Company recognized$1.1 million and $1.3 million of interest income on non-accrual loans and leases for the three and six months ended June 30, 2024, respectively.

The following table summarize the balance and activity within the allowance for credit losses - loans and leases, the components of the allowance for credit losses - loans and leases by loans and leases individually and collectively evaluated for impairment, and corresponding loan and lease balances by type for the periods presented:

The following table summarize the balance and activity within the allowance for credit losses - loans and leases, the components of the allowance for credit losses - loans and leases by loans and leases individually and collectively evaluated for impairment, loans acquired with deteriorated credit quality, and corresponding loan and lease balances by type for the periods presented:

The Company increased the allowance for credit losses - loans and leases by $7.3 million and $9.7 million for thethree and six months ended June 30, 2025, respectively. During the second quarter of 2025, a $3.2 million adjustment was made to the allowance for credit losses to account for acquired PCD loans, as a result of the First Security acquisition. The Company decreased the allowance for credit losses - loans and leases by $2.6 million and $2.0 million for thethree and six months ended June 30, 2024, respectively.

For loans individually evaluated for impairment, the Company increased the allowance for credit losses - loans and leases by $4.3 million and $2.8 million for thethree and six months ended June 30, 2025, and increased the allowance for credit losses for loans individually evaluated by $1.9 million and recaptured $3.7 million for thethree and six months ended June 30, 2024, respectively.

For loans and leases collectively evaluated for impairment, the allowance for credit losses increased by $3.0 million and $7.0 million for thethree and six months ended June 30, 2025, respectively. For loans and leases collectively evaluated for impairment, the allowance for credit losses decreased by $4.5 million and increased by $1.7 million for thethree and six months ended June 30, 2024, respectively.

The increase in the allowance for credit losses - loans and leases was mainly due to the PCD adjustment related to the First Security acquisition, increases in the collectively assessed portfolio, growth in the loan and lease portfolio, and worsening macroeconomic conditions.

The following table presents loans to borrowers experiencing financial difficulty and with modified terms for the periods presented:

The financial effect of the payment delay presented above reflects a six-month deferral of principal payments. The financial effect of the term modification presented above reflects a twelve month extension of maturity date and other miscellaneous term adjustments.

The financial effect of the loan modifications presented above for the three and six months ended June 30, 2024, reflects a three-months weighted average extension of maturity date.

The following table presents the amortized costs basis of loans that had a payment default as of the dates presented, and were modified in the twelve months prior to default:

Modified loans are either collectively assessed based on portfolio risk segment and risk rating or individually assessed for loans exceeding $500,000. Upon the Company’s determination that a modified loan has subsequently been deemed uncollectible, the loan (or a portion of the loan) is written off. Therefore, the amortized cost basis of the loan is reduced by the uncollectible amount and the allowance for credit losses is adjusted by the same amount.

There was $1.8 million and $2.1 million in outstanding commitments on modified loans as of June 30, 2025 and December 31, 2024.

The following table presents the amortized cost basis of collateral-dependent loans and leases, which are individually evaluated to determine expected credit losses as of the dates presented:

The following table presents the change in the balance of the allowance for credit losses - unfunded commitments as of the periods presented:

Note 6—Servicing Assets

Activity for servicing assets and the related changes in fair value for the periods presented was as follows:

Loans serviced for others are not included in the Condensed Consolidated Statements of Financial Condition. The unpaid principal balances of these loans serviced for others as of the dates presented were as follows:

Loan servicing revenue totaled$3.1 million and $3.2 million for thethree months ended June 30, 2025 and 2024, respectively. Loan servicing revenue totaled$6.1 million and $6.6 million for the six months ended June 30, 2025 and 2024, respectively.

Loan servicing asset revaluation, which represents the changes in fair value of servicing assets, resulted in a downward valuation adjustment of$2.1 million and $2.5 million for thethree months ended June 30, 2025 and 2024, respectively. Loan servicing asset revaluation resulted in a downward valuation adjustment of$3.2 million for each six months ended June 30, 2025 and 2024.

The fair value of servicing rights is highly sensitive to changes in underlying assumptions. Changes in secondary market premiums and prepayment speed assumptions have the most significant impact on the fair value of servicing rights. Generally, as interest rates rise on variable rate loans, loan prepayments increase due to an increase in refinance activity, which may result in a decrease in the fair value of servicing assets. Measurement of fair value is limited to the conditions existing and the assumptions used as of a particular point in time, and those assumptions may change over time. Refer to Note 15—Fair Value Measurement for further details.

Note 7—Other Real Estate Owned

Other real estate owned ("OREO") is included in accrued interest receivable and other assets in the Company's Condensed Consolidated Statements of Financial Condition. The following table presents the change in OREO for the periods presented:

At June 30, 2025 and December 31, 2024, the balance of real estate owned did not include any foreclosed residential real estate properties recorded as a result of obtaining physical possession of the property.

At June 30, 2025 and December 31, 2024, there was $1.4 million and $818,000 of consumer mortgage loans secured by residential real estate properties in foreclosure, respectively.

There wereno internally financed sales of OREO for thethree and six months ended June 30, 2025 or 2024.

Note 8—Leases

The Company enters into leases in the normal course of business primarily for its banking facilities and branches. The Company’s operating leases have varying maturity dates through year end 2036, some of which include renewal or termination options to extend the lease. In addition, the Company leases or subleases real estate to third parties. The Company includes lease extension and termination options in the lease term if, after considering relevant economic factors, it is reasonably certain the Company will exercise the option. In addition, the Company has elected to account for any non-lease components in its real estate leases as part of the associated lease component. The Company has also elected not to recognize leases with original lease terms of 12 months or less ("short-term leases") on the Company’s Condensed Consolidated Statements of Financial Condition.

Leases are classified at the lease commencement date. Lease expense for operating leases and short-term leases is recognized on a straight-line basis over the lease term. Right-of-use assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Right-of-use assets and lease liabilities are recognized at the lease commencement date based on the estimated present value of lease payments over the lease term.

The following table summarizes the amount and balance sheet line item for our operating lease right-of-use asset and liability as of the dates presented:

The Company uses its incremental borrowing rate at lease commencement to calculate the present value of lease payments when the rate implicit in a lease is not known. The Company’s incremental borrowing rate is based on the Federal Home Loan Bank ("FHLB") regular advance rate, adjusted for the lease term and other factors. At June 30, 2025, the weighted average discount rate of operating leases was 3.46% and the weighted average remaining life of operating leases was 4.9 years, compared to 3.19% and 5.0 years as of Dece mber 31, 2024.

The following table presents components of total lease costs included as a component of occupancy expense on the Condensed Consolidated Statements of Operations for the periods presented:

Operating cash flows paid for operating lease amounts included in the measure of lease liabilities were $976,000 and$1.2 million for the three months ended June 30, 2025 and 2024, respectively. Operating cash flows paid for operating lease amounts included in the measure of lease liabilities were $1.8 million and $2.1 million for thesix months ended June 30, 2025 and 2024, respectively.

During the six months ended June 30, 2024, the Company recorded $194,000 of impairment related to two branch facilities that were closed in the of the second quarter of 2024. Impairments were recognized on operating lease right-of-use assets and are reflected in other non-interest expense. There has been no impairment related to leases for the three or six months ended June 30, 2025.

The future minimum lease payments for operating leases, subsequent to June 30, 2025, as recorded on the Condensed Consolidated Statements of Financial Condition, are summarized as follows:

The total amount of minimum rentals to be received in the future on these subleases is approximately$1.2 million, and the leases have contractual lives extending through 2030. In addition to the above required lease payments, the Company has contractual obligations related primarily to information technology contracts and other maintenance contracts.

Note 9—Goodwill, Core Deposit Intangible and Other Intangible Assets

The following tables summarize the changes in the Company’s goodwill, core deposit intangible assets, and customer relationship intangible assets for the periods presented:

The Company added additional goodwill and core deposit intangible assets in conjunction with the First Security acquisition. Please refer to Note 3—Acquisition of a Business for further details.

The following table presents the estimated amortization expense for core deposit intangible and customer relationship intangible assets remaining at June 30, 2025:

Note 10—Income Taxes

The Company uses an estimated annual effective tax rate method in computing its interim tax provision. This effective tax rate is based on forecasted annual pre-tax income, permanent tax differences and statutory tax rates.

The effective tax rate for the six months ended June 30, 2025 and 2024 was 23.7% and 25.5%, respectively. The Company recorded discrete income tax benefit of$1.5 million and $564,000 related to the exercise of stock options and vesting of restricted shares for thesix months ended June 30, 2025 and 2024, respectively.

Net deferred tax assets increased to $57.1 million at June 30, 2025 compared to $56.5 million at December 31, 2024. The net increase in the total net deferred tax assets was primarily a result of the recognition of tax attributes from the First Security acquisition, offset by decreases in the unrealized losses on available-for-sale securities.

During the second quarter 2024, Illinois House Bill 4951 was enacted, which amends numerous Illinois tax law provisions, including a temporary limitation on Net Loss Deduction ("NLD") usage. For tax years 2024, 2025, and 2026, C Corporations are limited to applying a maximum of $500,000 of NLD to taxable income.

During July 2025, H.R. 1 was signed into law. The legislation includes several changes to federal tax law that generally allow for more favorable deductibility of certain business expenses beginning in 2025, including the restoration of immediate expensing of domestic R&D expenditures, reinstatement of 100% bonus depreciation, and more favorable rules for determining the limitation on business interest expense. These changes were not reflected in the income tax provision for the period ended June 30, 2025, as enactment occurred after the balance sheet date. The Company is currently evaluating the impact on future periods.

Note 11—Deposits

The composition of deposits was as follows as of the dates presented:

At June 30, 2025, the scheduled maturities of time deposits were:

The Company hedges interest rates on certain money market accounts using interest rate swaps through which the Company receives variable amounts and pays fixed amounts. Refer to Note 16—Derivative Instruments and Hedge Activities for additional discussion.

Note 12—Other Borrowings

The following is a summary of the Company’s other borrowings as of the dates presented:

Byline Bank has the capacity to borrow funds from the discount window of the Federal Reserve System. As of June 30, 2025 and December 31, 2024, there wereno outstanding advances under the Federal Reserve Bank ("FRB") discount window line. The Company pledges loans and leases as collateral for the FRB discount window borrowing. Refer to Note 5—Loan and Lease Receivables and Allowance for Credit Losses for additi onal discussion.

On January 17, 2024, the Company entered into a Letter Agreement with the FRB of Chicago that allowed the Bank to access the Bank Term Funding Program ("BTFP"). On January 22, 2024, the Company opened an advance of $200.0 million from the FRB as part of the BTFP. Under the terms of the BTFP, the Bank pledged securities to FRB Chicago as collateral for available advances. The advance carried a fixed interest rate of 4.91%. Advances under the BTFP were prepayable at any time without a prepayment penalty. On September 19, 2024, we repaid the BTFP advance in full.

At June 30, 2025, the Company had one $250.0 million variable-rate FHLB advance outstanding with an interest rate of 4.55% and maturity in September 2025. We also had one $130.0 million fixed-rate advance with an interest rate of 4.45% and maturity in July 2025. Advances from the FHLB are collateralized by residential real estate loans and commercial real estate loans. The Bank’s maximum borrowing capacity is limited to 35% of total assets. Required investment in FHLB stock is $4.50 for every $100 in advances thereafter.

Securities sold under agreements to repurchase represent a demand deposit product offered to customers that sweep balances in excess of the Federal Deposit Insurance Corporation insurance limit into overnight repurchase agreements. The Company pledges securities as collateral for the repurchase agreements. Refer to Note 4—Securities for additional discussion.

On October 13, 2016, we entered into a $30.0 million revolving credit agreement with a correspondent bank. Through subsequent amendments, the revolving credit agreement was reduced to $15.0 million. The amended revolving line of credit bears interest at either the Secured Overnight Financing Rate ("SOFR") plus 205 basis points or Prime Rate minus 75 basis points, not to be less than 2.00%, based on the Company’s election, which is required to be communicated at least three business days prior to the commencement of an interest period. If the Company fails to provide timely notification, the interest rate will be Prime Rate minus 75 basis points. At June 30, 2025 and December 31, 2024, the line of credit hadno outstanding balance.

On May 21, 2025, we entered into the Second Amendment to the Second Amended and Restated Term Loan and Revolving Credit Agreement with the lender, which is effective May 25, 2025, and provides for: (1) the renewal of the revolving line-of-credit facility of up to $15.0 million, and (2) extending its maturity date to May 24, 2026, subject to the existing Negative Pledge Agreement dated October 11, 2018, as amended.

The variable term loan was paid in full in January 2025, andat June 30, 2025, there wasno outstanding balance. At December 31, 2024, the variable term loan had an interest rate of 6.83% and an outstanding balance of $11.7 million.

The following table presents short-term credit lines, subject to collateral requirements, available for use as of the dates presented:

The Company hedges interest rates on borrowed funds using interest rate swaps through which the Company receives variable amounts and pays fixed amounts. Refer to Note 16—Derivative Instruments and Hedge Activities for additional discussion.

Note 13—Subordinated Notes and Junior Subordinated Debentures

Subordinated Notes

In 2020, the Company issued $75.0 million in fixed-to-floating rate subordinated notes that mature on July 1, 2030. The subordinated notes bear a fixed interest rate of 6.00% until July 1, 2025 and a floating interest rate equal to the three-month SOFR, plus 588 basis points thereafter until maturity. As of July 1, 2025, the floating rate was 10.17%. The transaction resulted in debt issuance costs of approximately $1.7 million that is being amortized over 10 years. The subordinated notes qualify as Tier 2 capital for regulatory capital purposes.

As of June 30, 2025, the net liability outstanding of the subordinated notes was $74.1 million, which is net of $873,000 of remaining debt issuance costs. The Company intends to redeem the notes on the next interest payment date, which is October 1, 2025, subject to approval of the Federal Reserve. Remaining debt issuance costs will be recognized upon redemption.

On August 7, 2025, the Company issued $75.0 million in aggregate principal amount of 6.875% fixed-to-floating rate subordinated notes that mature on August 15, 2035. The subordinated notes bear a fixed interest rate of 6.875% until August 15, 2030 and a floating interest rate equal to the then current three-month SOFR plus 322 basis points thereafter until maturity. The Company may, at its option, redeem the notes, in whole or in part, on a quarterly basis beginning on August 15, 2030, subject to obtaining the prior approval of the Federal Reserve to the extent such approval is then required. The subordinated notes are intended to qualify as Tier 2 capital for regulatory capital purposes. The transaction resulted in debt issuance costs of approximately $1.1 million that will be amortized over 10 years.

Junior subordinated debentures

Each of the junior subordinated debentures was issued to an underlying statutory trust (the "Trusts"), which issued trust preferred securities and used the proceeds from the issuance of the trust preferred securities to purchase the junior subordinated debentures of the Company. The debentures represent the sole asset of the Trusts. The Trusts are not consolidated with the Company. Accordingly, the Company reports the subordinated debentures held by the Trusts as liabilities. The Company owns all of the common securities of each trust and pays interest on each quarterly. The junior subordinated debentures qualify, and are treated as, Tier 1 regulatory capital of the Company subject to regulatory limitations. The trust preferred securities issued by each trust rank equally with the common securities in right of payment, except that if an event of default under the indenture governing the notes has occurred and is continuing, the preferred securities will rank senior to the common securities in right of payment.

As of the dates presented, the Company’s junior subordinated debentures by issuance were as follows:

(1)SOFR is three-month SOFR and the spread adjustment is 0.26161%

(2)Assumed as part of the Company's recapitalization of its predecessor.

(3)Assumed in May 2018 as part of an acquisition.

(4)Assumed in July 2023 as part of an acquisition

Note 14—Commitments and Contingent Liabilities

Legal contingencies—In the ordinary course of business, the Company and Bank have various outstanding commitments and contingent liabilities that are not recognized in the accompanying consolidated financial statements. In addition, the Company may be a defendant in certain claims and legal actions arising in the ordinary course of business. In the opinion of management, after consultation with legal counsel, the ultimate disposition of these matters is currently not expected to have a material adverse effect on the Company’s Consolidated Financial Statements.

Operating lease commitments—Refer to Note 8—Leases for discussion of operating lease commitments.

Commitments to extend credit—The Company is party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit and standby letters of credit. Those instruments involve, to varying degrees, elements of credit and interest rate risk in excess of the amount recognized in the Condensed Consolidated Statements of Financial Condition. The contractual or notional amounts of those instruments reflect the extent of involvement the Company has in particular classes of financial instruments.

The Company’s exposure to credit loss in the event of non-performance by the other party to the financial instrument for commitments to extend credit and letters of credit is represented by the contractual or notional amount of those instruments. The Company uses the same credit policies in making commitments and conditional obligations as it does for funded instruments. The Company does not anticipate any material losses as a result of the commitments and letters of credit. Refer to Note 5—Loans and Lease Receivables and Allowance for Credit Losses for additional discussion on the reserve for unfunded commitments.

The following table summarizes the contract or notional amount of outstanding loan and lease commitments at the dates presented:

Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since many of the commitments are expected to expire without being drawn upon, the total commitment amount does not necessarily represent future cash requirements. The Company evaluates each customer’s creditworthiness on a case-by-case basis. The amount of collateral obtained, if deemed necessary by the Company upon extension of credit, is based on management’s credit evaluation of the counterparty. Collateral is primarily obtained in the form of commercial and residential real estate (including income producing commercial properties).

Letters of credit are conditional commitments issued by the Company to guarantee the performance of a customer to a third party. Those guarantees are primarily issued to support public and private borrowing arrangements, bond financing and similar transactions. The credit risk involved in issuing letters of credit is essentially the same as that involved in extending loan facilities to customers.

Commitments to make loans are generally made for periods of 90 days or less. The fixed rate loan commitments have interest rates ranging from 2.69% to 15.00% and maturities up to 2046. Variable rate loan commitments have interest rates ranging from 3.50% to 17.75% and maturities up to 2048.

Note 15—Fair Value Measurement

Fair value is the exchange price that would be received for an asset or paid to transfer a liability (exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. In addition, the Company has the ability to obtain fair values for markets that are not accessible.

These types of inputs create the following fair value hierarchy:

Level 1—Quoted prices in active markets for identical assets or liabilities.

Level 2—Quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-derived valuations whose inputs are observable or whose significant value drivers are observable.

Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the asset or liability. Unobservable inputs are used to measure fair value to the extent that observable inputs are not available. The Company’s own data used to develop unobservable inputs may be adjusted for market considerations when reasonably available.

The categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to assets and liabilities.

The Company used the following methods and significant assumptions to estimate fair value for certain assets measured and carried at fair value on a recurring basis:

Securities available-for-sale—The Company obtains fair value measurements from an independent pricing service. Management reviews the procedures used by the third party, including significant inputs used in the fair value calculations. The fair value measurements consider observable data that may include dealer quotes, market spreads, cash flows, the U.S. Treasury yield curve, live trading levels, trade execution data, market consensus prepayment speeds, credit information and the bond’s terms and conditions, among other things. When market quotes are not readily accessible or available, alternative approaches are utilized, such as matrix or model pricing.

The Company’s methodology for pricing non-rated bonds focuses on three distinct inputs: equivalent rating, yield and other pricing terms. To determine the rating for a given non-rated municipal bond, the Company references a publicly issued bond by the same issuer if available as well as other additional key metrics to support the credit worthiness. Typically, pricing for these types of bonds would require a higher yield than a similar rated bond from the same issuer. A reduction in price is applied to the rating obtained from the comparable bond, as the Company believes if liquidated, a non-rated bond would be valued less than a similar bond with a verifiable rating. The reduction applied by the Company is one notch lower (i.e. a "AA" rating for a comparable bond would be reduced to "AA-" for the Company’s valuation). In 2025 and 2024, all of the ratings derived by the Company were "BBB-" or better with and without comparable bond proxies. All of the ratings of non-Agency backed bonds derived by the Company were investment grade. The fair value measurement of municipal bonds is sensitive to the rating input, as a higher rating typically results in an increased valuation. The remaining pricing inputs used in the bond valuation are observable. Based on the rating determined, the Company obtains a corresponding current market yield curve available to market participants. Other terms including coupon, maturity date, redemption price, number of coupon payments per year, and accrual method are obtained from the individual bond term sheets.

Equity and other securities—The Company utilizes the same fair value measurement methodology for equity and other securities as detailed in the securities available-for-sale portfolio above. The fair value of equity securities subject to contractual sale restrictions is measured on the basis of the market price of similar unrestricted equity securities. The fair value is only adjusted for the effect of the restrictions when the restriction of the sale is a characteristic of the equity itself and not based on the holder of the security.

Servicing assets—Fair value is based on a loan-by-loan basis taking into consideration the original term to maturity, the current age of the loan and the remaining term to maturity. The valuation methodology utilized for the servicing assets begins with generating estimated future cash flows for each servicing asset, based on their unique characteristics and market-based assumptions for prepayment speeds and costs to service. The present value of the future cash flows are then calculated utilizing market-based discount rate assumptions.

Derivative instruments—Interest rate derivatives are valued by a third party, using models that primarily use market observable inputs, such as yield curves, and are validated by comparison with valuations provided by the respective counterparties. Derivative financial instruments are included in accrued interest receivable and other assets, and accrued interest payable and other liabilities in the Condensed Consolidated Statements of Financial Condition.

The following tables summarize the Company’s financial assets and liabilities that were measured at fair value on a recurring basis at the dates presented:

The following table presents additional information about financial assets measured at fair value on recurring basis for which the Company used significant unobservable inputs (Level 3):

The Company didnot have any transfers to or from Level 3 of the fair value hierarchy during thesix months ended June 30, 2025 and 2024.

The following table presents additional information about the unobservable inputs used in the fair value measurements on recurring basis that were categorized within Level 3 of the fair value hierarchy as of June 30, 2025:

The Company used the following methods and significant assumptions to estimate fair value for certain assets measured and carried at fair value on anon-recurring basis:

Individually evaluated loans—The Company individually evaluates loans that do not share similar risk characteristics, including non-accrual loans. Specific allowance for credit losses is measured based on a discounted cash flow of ongoing operations, discounted at the loan's original effective interest rate, or a calculation of the fair value of the underlying collateral less estimated selling costs. Valuations of individually assessed loans that are collateral dependent are supported by third party appraisals in accordance with the Bank's credit policy. Accordingly, individually evaluated loans are classified as Level 3.

Assets held for sale—Assets held for sale consist of former branch locations and real estate previously purchased for expansion. Assets are considered held for sale when management has approved to sell the assets following a branch closure or other events. The properties are being actively marketed and transferred to assets held for sale based on the lower of carrying value or its fair value, less estimated costs to sell. The Company records assets held for sale on the Condensed Consolidated Statements of Financial Condition within accrued interest receivable and other assets.

Other real estate owned—Certain assets held within other real estate owned represent real estate or other collateral that has been adjusted to its estimated fair value, less cost to sell, as a result of transferring from the loan portfolio at the time of foreclosure or repossession and based on management’s periodic impairment evaluation. From time to time, non-recurring fair value adjustments to other real estate owned are recorded to reflect partial write-downs based on an observable market price or current appraised value of property.

Adjustments to fair value based on such non-recurring transactions generally result from the application of lower-of-cost-or-market accounting or write-downs of individual assets due to impairment. The following tables summarize the Company’s assets that were measured at fair value on a non-recurring basis, as of the dates presented:

The following methods and assumptions were used by the Company in estimating fair values of other assets and liabilities for disclosure purposes:

Cash and cash equivalents and interest bearing deposits with other banks—For these short-term instruments, the carrying amount is a reasonable estimate of fair value.

Securities held-to-maturity—The Company obtains fair value measurements from an independent pricing service. Management reviews the procedures used by the third party, including significant inputs used in the fair value calculations. The fair value measurements consider observable data that may include dealer quotes, market spreads, cash flows, the U.S. Treasury yield curve, live trading levels, trade execution data, market consensus prepayment speeds, credit information and the bond’s terms and conditions, among other things. When market quotes are not readily accessible or available, alternative approaches are utilized, such as matrix or model pricing.

Restricted stock—The fair value has been determined to approximate cost.

Loans held for sale—The fair value of loans held for sale are based on quoted market prices, where available, and determined by discounted estimated cash flows using interest rates approximating the Company’s current origination rates for similar loans adjusted to reflect the inherent credit risk.

Loan and lease receivables, net—For certain variable rate loans that reprice frequently and with no significant changes in credit risk, fair value is estimated at carrying value. The fair value of other types of loans is estimated using an exit price notion. It is estimated by discounting future cash flows, using current rates at which similar loans would be made to borrowers with similar credit ratings and for the same remaining maturities.

Deposits—The fair value of demand deposits, savings accounts, and certain money market deposits is the amount payable on demand at the reporting date. The fair value of fixed-maturity certificates of deposit is estimated by discounting future cash flows, using rates currently offered for deposits of similar remaining maturities.

Federal Home Loan Bank advances—The fair value of FHLB advances is estimated by discounting the agreements based on maturities using rates currently offered for FHLB advances of similar remaining maturities adjusted for prepayment penalties that would be incurred if the borrowings were paid off on the measurement date.

Securities sold under agreements to repurchase—The carrying amount approximates fair value due to maturities of less than ninety days.

Term Loan—The carrying amount approximates fair value given the variable interest rate and repricing of interest.

Subordinated notes—The fair value is based on available market prices.

Junior subordinated debentures—The fair value of junior subordinated debentures, in the form of trust preferred securities, is determined using rates currently available to the Company for debt with similar terms and remaining maturities.

Accrued interest receivable and payable—The carrying amount approximates fair value.

Commitments to extend credit and letters of credit—The fair values of these off-balance sheet commitments to extend credit and commercial and letters of credit are not considered practicable to estimate because of the lack of quoted market prices and the inability to estimate fair value without incurring excessive costs.

The estimated fair values of financial instruments not carried at fair value and levels within the fair value hierarchy are as follows:

Note 16—Derivative Instruments and Hedge Activities

As required by ASC 815, the Company records all derivatives on the Condensed Consolidated Statements of Financial Condition at fair value. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative, whether the Company has elected to designate a derivative in a hedging relationship and apply hedge accounting and whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. The Company records derivative assets and derivative liabilities on the Condensed Consolidated Statements of Financial Condition within accrued interest receivable and other assets and accrued interest payable and other liabilities, respectively. The following tables present the fair value of the Company’s derivative financial instruments and classification on the Condensed Consolidated Statements of Financial Condition as of the dates presented:

Interest rate swaps designated as cash flow hedges—Cash flow hedges of interest payments associated with certain financial instruments had notional amounts totaling $650.0 million as of June 30, 2025 and December 31, 2024, respectively. The Company assesses the effectiveness of each hedging relationship by comparing the changes in fair value of the derivatives hedging instrument with the fair value of the designated hedged transactions. As of June 30, 2025, the cash flow hedges aggregating $650.0 million in notional amounts are comprised of $400.0 million pay-fixed interest rate swaps associated with certain deposits and other borrowings, and $250.0 million receive-fixed interest rate swaps associated with certain variable rate loans.

As of June 30, 2025, pay-fixed interest rate swaps are comprised of five effective hedges. The receive-fixed interest rate swaps are comprised of four effective hedges with notional amounts comprised of $200.0 million. A $50.0 million forward starting receive-fixed interest rate swap associated with certain variable rate loans will become effective in March 2026.

For derivatives designated and that qualify as cash flow hedges of interest rate risk, the unrealized gain or loss on the derivatives is recorded in accumulated other comprehensive income (loss) and subsequently reclassified into interest income or expense in the same period during which the hedged transaction affects earnings. Amounts reported in accumulated other comprehensive income (loss) related to derivatives will be reclassified to interest income or expense as interest payments are made on the hedged instruments. Interest recorded on these swap transactions included $3.5 million and $4.7 million of interest income recorded for each of thethree months ended June 30, 2025 and 2024, and is reported as a component of interest expense on deposits and other borrowings. Interest recorded on these swap transactions included $7.2 million and $9.6 million of interest income recorded duringsix months ended June 30, 2025 and 2024, respectively, and is reported as a component of interest expense on deposits and other borrowings. As of June 30, 2025, the Company estimates $11.9 million of the net unrealized gain to be reclassified as a net decrease to interest expense during the next twelve months.

Accumulated other comprehensive income (loss) also includes the amortization of the remaining balance related to terminated interest rate swaps designated as cash flow hedges, which are over the original life of the cash flow hedge. In March 2023, the Company terminated interest rate swaps designated as cash flow hedges totaling $100.0 million, of which $50.0 million became effective in May 2023 and $50.0 million became effective in June 2023. The transaction resulted in a gain of $4.2 million, net of tax, which was the clean value at termination date and began amortizing as a decrease to interest expense on the effective dates. The remaining unamortized balance was $2.4 million and $2.9 million as of June 30, 2025 and December 31, 2024, respectively.

The following table reflects the cash flow hedges as of June 30, 2025:

Receive rates are determined at the time the swaps become effective. As of June 30, 2025, the weighted average pay rates of the five effective pay-fixed hedges for $400.0 million were 1.07% and the weighted average receive rates were 4.32%. As of June 30, 2025, the weighted average pay rates of the receive-fixed interest rate swaps of $200.0 million were 7.50% and the weighted average receive rates were 7.30%.

The following table reflects the net gains (losses) recorded in accumulated other comprehensive income (loss) and the Condensed Consolidated Statements of Operations relating to the cash flow and fair value derivative instruments for the periods presented:

Interest rate swaps designated as fair value hedges—A fair value hedge associated with certain fixed-rate investment securities had notional amounts totaling $100.0 million as of June 30, 2025. The Company assesses the effectiveness of the hedging relationship by comparing the changes in fair value of the derivatives hedging instrument with the fair value of the designated hedged securities.

The following table reflects the fair value hedge as of June 30, 2025:

At June 30, 2025, the amortized cost basis of the closed portfolios of available-for-sale securities used in this hedging relationship was $624.7 million, and included a cumulative basis adjustment associated with this hedging relationship of$18,000. This represents the amount of fair value hedging adjustments included in the carrying amounts of fixed-rate investment securities designated in fair value hedging arrangement. There were no interest rate swaps designated as fair value hedges at December 31, 2024.

Other interest rate derivatives—Derivatives not designated as hedges are not speculative and are used to manage the Company’s exposure to interest rate movements and other identified risks but do not meet the strict hedge accounting requirements and/or the Company has not elected to apply hedge accounting. Changes in the fair value of derivatives not designated in hedging relationships are recorded directly in earnings.

The total combined notional amount was $1.1 billion as of June 30, 2025 with maturities ranging from September 2025 to March 2033. The fair values of the interest rate derivative agreements are reflected in other assets and other liabilities with corresponding gains or losses reflected in non-interest income. During the three months ended June 30, 2025 and 2024, there were $1.1 million and $110,000 of net transaction fees, included in other non-interest income, related to these derivative instruments. During thesix months ended June 30, 2025 and 2024, there were$1.6 million and $114,000 of net transaction fees, included in other non-interest income, related to these derivative instruments.

These instruments are inherently subject to market risk and credit risk. Market risk is associated with changes in interest rates and credit risk relates to the Company’s risk of loss when the counterparty to a derivative contract fails to perform according to the terms of the agreement. Market and credit risks are managed and monitored as part of the Company’s overall asset-liability management process. The credit risk related to derivatives entered into with certain qualified borrowers is managed through the Company’s loan underwriting process. The Company’s loan underwriting process also approves the Bank’s swap counterparty used to mirror the borrowers’ swap. The Company has a bilateral agreement with each swap counterparty that provides that fluctuations in derivative values are to be fully collateralized with either cash or securities.

The following table reflects other interest rate derivatives as of June 30, 2025:

Other derivatives—The Company has entered into risk participation agreements with counterparty banks to assume a portion of the credit risk related to borrower transactions. As of June 30, 2025 and December 31, 2024, the notional amount of risk participated in was $9.1 million and $10.4 million, respectively, and the notional amount of risk participated out was $6.6 million and $6.8 million, respec tively. The credit risk related to these other derivatives is managed through the Company’s loan underwriting process. Additionally, the Company enters into foreign currency contracts to manage foreign exchange risk associated with certain customer foreign currency transactions. These transactions were not material to the consolidated financial statements as of June 30, 2025 and December 31, 2024. The fair values of the credit derivatives is reflected in accrued interest receivable and other assets and accrued interest payable and other liabilities with corresponding gains or losses reflected in non-interest income or other comprehensive income.

The Company has agreements with its derivative counterparties that contain a cross-default provision under which if the Company defaults on any of its indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender, then the Company could also be declared in default on its derivative obligations. The Company also has agreements with certain derivative counterparties that contain a provision where if the Company fails to maintain its status as a well or adequately capitalized institution, then the counterparty could terminate the derivative positions and the Company would be required to settle its obligations resulted in a net asset position.

The following table reflects amounts included in non-interest income in the Condensed Consolidated Statements of Operations relating to derivative instruments that are not designated in a hedging relationship for the periods presented:

The Company records interest rate derivatives subject to master netting agreements at their gross value and does not offset derivative asset and liabilities on the Condensed Consolidated Statements of Financial Condition. The table below summarizes the Company’s interest rate derivatives and offsetting positions as of the dates presented:

As of June 30, 2025, the fair value of derivatives in a net liability position, which includes accrued interest but excludes any adjustment for nonperformance risk, related to these agreements was $14.7 million. If the Company had breached any of these provisions at June 30, 2025, it could have been required to settle its obligations under the agreements at their termination value less offsetting positions of $4.2 million. For purposes of this disclosure, the amount of posted collateral by the Company and counterparties is limited to the amount offsetting the derivative asset and derivative liability.

Note 17 – 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 June 30, 2025, there were 477,301 shares available for future grants under the Omnibus Plan.

The Company primarily grants time-based restricted share awards that vest over aone tofour 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 and measured against a peer group consisting of publicly-traded bank holding companies. Results will be measured cumulatively at the end of the three years. Any earned shares will vest on the third anniversary of the grant date.

During 2025, the Company granted 327,951 shares of restricted common stock, par value $0.01 per share. Of this total,246,212 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 6,095 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 thethree years and any earned shares will vest on the third anniversary of the grant date.

The following table discloses the changes in restricted shares for thesix months ended June 30, 2025:

A total of 318,139 restricted shares vested during the six months ended June 30, 2025. A total of 244,548 restricted shares vested during the year ended December 31,2024. The fair value of restricted shares that vested during the six months ended June 30, 2025 was$9.1 million. The fair value of restricted shares that vested during the year ended December 31,2024 was $5.2 million.

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 Condensed Consolidated Statements of Operations. The fair value of the total stock return performance-based awards granted in 2025 and 2024 were calculated based on a Monte Carlo simulation, using the following assumptions:

The following table summarizes restricted stock compensation expense for the periods presented:

The fair value of the unvested restricted stock awards at June 30, 2025 was$20.5 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 andno future grants can be made under this plan.

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 fromone tofive years and have 10-year contractual terms. Stock volatility was computed as the average of the volatilities of peer group companies. All outstanding stock options were fully vested and exercised at June 30, 2025.

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.

The following table discloses the activity in shares subject to options and the weighted average exercise prices, in actual dollars, for thesix months ended June 30, 2025:

A total of 334,423 stock options were exercised during thesix months ended June 30, 2025. Proceeds from exercise of stock options were $334,000 and had a related tax benefit of $1.3 million for the six months ended June 30, 2025. There were 434,141 stock options exercised during the year ended December 31, 2024. Proceeds from the exercise of stock options were$2.6 million with a related tax benefit of $1.6 million for the year ended December 31, 2024. No stock option compensation expense was recognized for thesix months ended June 30, 2025 or the year ended December 31, 2024.

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.

The following table discloses the activity in shares subject to options under the FEB Plan and the weighted average exercise prices, in actual dollars, for thesix months ended June 30, 2025:

Under the FEB plan, no stock options were exercised during the six months ended June 30, 2025. A total of 57,686 stock options were exercised under the FEB plan during the during the year ended December 31, 2024, with proceeds of $675,000 and a related tax benefit of $252,000.

Note 18—Earnings per Share

A reconciliation of the numerators and denominators for earnings per common share computations is presented below. Incremental shares represent outstanding stock options for which the exercise price is less than the average market price of the Company’s common stock during the periods presented. Options to purchase 45,449 and 637,405 shares of common stock were outstanding as of June 30, 2025 and 2024, respectively. There were 768,776 and 768,246 restricted stock awards outstanding at June 30, 2025 and 2024, respectively. For the three and six months ended June 30, 2025 and 2024, there wereno anti-dilutive weighted average shares outstanding.

The following represent the calculation of basic and diluted earnings per share for the periods presented:

Note 19—Stockholders’ Equity

A summary of the Company’s preferred and common stock at the dates presented is as follows:

On December 6, 2023, we announced that our Board of Directors approved a stock repurchase program authorizing the purchase of up to an aggregate of 1,250,000 shares of the Company’s outstanding common stock. The program was in effect from January 1, 2024 until December 31, 2024. No shares were repurchased under this program.

On December 5, 2024, we announced that our Board of Directors approved a new stock repurchase program authorizing the purchase of up to an aggregate of 1,250,000 shares of the Company’s outstanding common stock. The program is in effect from January 1, 2025 until December 31, 2025, unless terminated earlier. The shares may, at the discretion of management, be repurchased from time to time in open market purchases as market conditions warrant or in privately negotiated transactions. The Company is not obligated to purchase any shares under the program, and the program may be discontinued at any time. The actual timing, number and share price of shares purchased under the repurchase program will be determined by the Company at its discretion and will depend on a number of factors, including the market price of the Company’s stock, general market and economic conditions and applicable legal requirements. The shares authorized to be repurchased represented approximately 2.8% of the Company’s outstanding common stock at December 31, 2024.

We purchased 543,599 and 569,599 shares under the stock repurchase program during the three and six months ended June 30, 2025, with costs of $13.1 million and $13.8 million, respectively. We didnot repurchase any shares under the stock repurchase program during the three and six months ended June 30, 2024.

On April 1, 2025 we issued 1,586,542 shares of our common stock in connection with the First Security acquisition. Please see Note 3—Acquisition of a Business for additional discussion.

On June 12, 2025, the Estate of Daniel L. Goodwin (the "Estate") and Equity Shares Investors, LLC, an affiliate of the Estate (the "Selling Stockholders"), completed their sale of 4,282,210 shares (the "Shares") of our common stock in a registered public offering (the "Offering") pursuant to the Company’s Registration Statement on Form S-3 filed under the Securities Act of 1933, as amended, that became automatically effective upon filing on June 10, 2025. The Shares were sold pursuant to an Underwriting Agreement, dated June 10, 2025 (the "Underwriting Agreement"), among the Company, the Selling Stockholders and J.P. Morgan Securities LLC, as sole underwriter for the Offering (the "Underwriter").

The Company did not receive any proceeds from the sale of the Shares by the Selling Stockholders. In addition, the Company purchased 418,235 of the Shares from the Underwriter (the "Stock Repurchase") at a price per share of $23.91, which was equal to the price per share paid by the Underwriter to the Selling Stockholders in the Offering. The Stock Repurchase was executed under the Company’s existing stock repurchase program authorized on January 1, 2025. Certain of the Company’s directors purchased an aggregate of $1.3 million of the Shares in the Offering at the public offering price and on the same terms as the other purchasers in the Offering.

Repurchased shares are recorded as treasury shares on the trade date using the treasury stock method, and the cash paid is recorded as treasury stock. Treasury stock acquired is recorded at cost and is carried as a reduction of stockholders’ equity in the Condensed Consolidated Statements of Financial Condition.

For the three months ended June 30, 2025 and 2024, cash dividends were declared and paid to stockholders of record of our common stock of $0.10 and $0.09 per share, respectively. For the six months ended June 30, 2025 and 2024, cash dividends were declared and paid to stockholders of record of our common stock of $0.20 and $0.18 per share, respectively.

On July 22, 2025, our Board of Directors declared a cash dividend of $0.10 per share payable on August 19, 2025 to stockholders of record of our common stock as of August 5, 2025.

Note 20—Consolidated Statements of Changes in Accumulated Other Comprehensive Income (Loss)

The following table summarizes the changes in accumulated other comprehensive income (loss) for the dates presented:

Note 21—Segment Information

The Company hasone reportable segment: banking operations. Loans and leases, securities, deposits, and non-interest income provide the revenues of the banking operation. Loan and lease products offered to customers generate a majority of the Company’s interest and fee income. Additionally, deposit products offered to customers generate fees and service charge income. Interest income earned on securities, and net gains on the sales of loans to third parties are other sources of revenue. Interest expense, provision for credit losses, salaries and employee benefits, and data processing provide the significant expenses in banking operations. These significant expenses are the same as those disclosed in the Company’s Consolidated Statements of Operations and Consolidated Statements of Cash Flows. Noncash items such as depreciation and amortization are also disclosed in the Company’s Consolidated Statements of Operations and Consolidated Statements of Cash Flows.

The Company’s chief operating decision makers are the Chief Executive Officer and the President. The chief operating decision makers are provided with consolidated balance sheets, income statements, and net interest margin analyses in order to evaluate revenue streams, significant expenses, and budget-to-actual results in assessing the Company’s segment and determining the allocation of resources. Additionally, the chief operating decision makers review performance of various components of banking operations, such as loan portfolio types, funding sources, and overhead, to assess product pricing and significant expenses and to evaluate return on assets. The chief operating decision makers use consolidated net income to benchmark the Company against its competitors. The benchmarking analysis coupled with monitoring budget-to-actual results are used in assessing performance and in establishing compensation.

The accounting policies of the banking operations are the same as those described in Note 1–Business and Summary of Significant Accounting Policies. Additional information about these policies can be found in Note 1 of our audited Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2024, which we filed with the SEC on February 28, 2025. All operations are domestic.

(1) Other segment items include: legal, audit, and other professional fees, other occupancy expense, regulatory assessments, and advertising and promotion expense.