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Summary of Significant Accounting Policies (Policies) | 12 Months Ended
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Dec. 31, 2024
Summary of Significant Accounting Policies |
Nature of Operations | Nature of Operations - Old Second Bancorp, Inc. (the “Company”) is a corporation organized under the laws of the State of Delaware in 1981 that serves as the bank holding company for its wholly-owned subsidiary bank, Old Second National Bank. Old Second National Bank (the “Bank”) is a national banking association headquartered in Aurora, Illinois, that operates through 53 banking centers located in Cook, DeKalb, DuPage, Kane, Kendall, LaSalle and Will counties in Illinois. The Bank is a full-service banking business, offering a broad range of deposit products, trust and wealth management services, and lending services, including commercial, residential and consumer loans. We also offer a full complement of electronic banking services, such as online and mobile banking and corporate cash management products. ​ The consolidated financial statements of the Company include the financial statements of the Bank and its wholly-owned subsidiaries, River Street Advisors, LLC, an investment advisory/management service company, Old Second Affordable Housing Fund, L.L.C., which provides down payment assistance for home ownership to qualified individuals, and Station I, LLC, Station II, LLC, and Station III, LLC, which hold property acquired by the Bank through foreclosure or in the ordinary course of collecting a debt previously contracted with borrowers. The Company uses the accrual basis of accounting for financial reporting purposes. Certain amounts in prior year financial statements have been reclassified to conform to the 2024 presentation.
Use of Estimates | Use of Estimates – The preparation of consolidated financial statements in conformity with generally accepted accounting principles (“GAAP”) and following general practices within the banking industry requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Although these estimates and assumptions are based on the best available information, actual results could differ from those estimates.
Principles of Consolidation | Principles of Consolidation – The accompanying consolidated financial statements include the accounts and results of operations of the Company and its subsidiaries after elimination of all significant intercompany accounts and transactions. Assets held in a fiduciary or agency capacity are not assets of the Company or its subsidiaries and are not included in the consolidated financial statements.
Segment Reporting | Segment Reporting –The Company has one operating segment, which is community banking. While our management monitors the revenue streams of our various products and services, the Company’s operations are managed and financial performance is evaluated on a company-wide basis. Accordingly, all of the Company’s operations are considered to be aggregated in one reportable segment.
Concentration of Credit Risk | Concentration of Credit Risk – Most of the Company’s business activity is with customers located within Cook, DeKalb, DuPage, Kane, Kendall, LaSalle and Will counties in Illinois. These banking centers surround or are within the Chicago metropolitan area. Therefore, the Company’s exposure to credit risk is significantly affected by changes in the economy in that market area since the Bank generally makes loans within this market. There are no significant concentrations of loans where the customers’ ability to honor loan terms is dependent upon a single economic sector.
Cash and Cash Equivalents | Cash and Cash Equivalents – For purposes of the Consolidated Statements of Cash Flows, management has defined cash and cash equivalents to include cash and due from banks, interest-earning deposits in other financial institutions, and other short-term investments, such as federal funds sold and securities purchased under agreements to resell. The classification of cash and cash equivalents includes those assets held in the form of cash or liquid instruments with an original maturity of 90 days or less.
Securities | Securities – All of the Company’s securities are classified as available-for-sale, and are carried at fair value, with unrealized gains or losses, net of tax, recorded in stockholders’ equity as a separate component of accumulated other comprehensive (loss) income. ​ Realized securities gains or losses, which are reported in securities losses, net, in the Consolidated Statements of Income, are recognized on a trade date basis and are determined using the specific identification method. Discounts are accreted into interest income over the estimated life of the related security and premiums are amortized into income to the earlier of the call date or estimated life of the related security using the level yield method. ​ The Company has made a policy election to exclude accrued interest income from the amortized cost basis of available-for-sale debt securities and report accrued interest separately in other assets in the Consolidated Balance Sheets. A debt security is placed on nonaccrual status at the time we no longer expect to receive all contractual amounts due, which is generally at 90 days past due. Accrued interest for a security placed on nonaccrual is reversed against interest income. Accordingly, we do not recognize an allowance for credit loss against accrued interest receivable. ​ ​ For available-for-sale debt securities in an unrealized loss position, we first assess whether we intend to sell, or it is more likely than not that we will be required to sell the security, prior to the recovery of its amortized cost basis. If either of the above criteria is met, the security’s amortized cost basis is written down to fair value through earnings. When the criteria above is not met, we evaluate whether the decline in fair value is the result of credit losses or other factors. In making this assessment, we review changes to the rating of the security by a rating agency, an increase in defaults on the underlying collateral, and the extent to which the securities are issued by the federal government or its agencies, including the amount of the guarantee issued by those agencies, among other factors. If this assessment indicates that a credit loss exists, we compare the present value of cash flows expected to be collected from the security with the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis for the security, a credit loss exists and an allowance for credit losses is recorded through earnings, limited to the amount that the fair value of the security is less than its amortized cost basis. Any impairment that has not been recorded through an allowance for credit losses is recognized in other comprehensive (loss) income, net of taxes. ​ Changes in the allowance for credit losses are recorded as a provision for (or reversal of) credit loss expense. Losses are charged against the allowance when management believes the uncollectibility of an available for sale debt security is confirmed or when either of the criteria regarding intent or requirement to sell is met.
Federal Home Loan Bank and Federal Reserve Bank Stock | Federal Home Loan Bank and Federal Reserve Bank Stock – The Company owns the stock of the Federal Home Loan Bank of Chicago (“FHLBC”) and the Federal Reserve Bank of Chicago (“FRBC”). Both of these entities require the Bank to invest in their nonmarketable stock as a condition of membership. The FHLBC is a governmental sponsored entity. The Bank continues to utilize the various products and services of the FHLBC and management considers this stock to be a long-term investment. FHLBC members are required to own a certain amount of stock based on the level of borrowings and other factors, and may invest in additional amounts. FHLBC stock is carried at cost, classified as a restricted security, and periodically evaluated for impairment based on ultimate recovery of par value. The Company’s ability to redeem the shares owned is dependent on the redemption practices of the FHLBC. The Company records dividends in income on the ex-dividend date. FRBC stock is redeemable at par, and therefore fair value equals cost.
Loans Held-for-Sale | Loans Held-for-Sale – The Bank originates residential mortgage loans, which consist of loan products eligible for sale to the secondary market. Residential mortgage loans eligible for sale in the secondary market are carried at fair market value. The fair value of loans held-for-sale is determined using quoted secondary market prices on similar loans. ​ Mortgage loans held for sale are generally sold with servicing rights retained. The carrying value of mortgage loans is reduced by the amount allocated to the servicing right. Gains and losses on sales of mortgage loans are based on the difference between the selling price and the carrying value of the related sold loan.
Loans | Loans – Loans held-for-investment are carried at the principal amount outstanding, net of premiums and discounts associated with acquisition date fair value adjustments on acquired loans, deferred loan fees and costs, and any direct principal charge-offs. The Company has made a policy election to exclude accrued interest from the amortized cost basis of loans and report accrued interest separately from the related loan balance in other assets in the Consolidated Balance Sheets. ​ Interest income on loans is accrued based on principal amounts outstanding. Loan and lease origination fees, commitment fees, and certain direct loan origination costs are deferred and amortized over the life of the related loans or commitments as a yield adjustment. Fees related to standby letters of credit, whose ultimate exercise is remote, are amortized into fee income over the estimated life of the commitment. Other related fees are recognized as fee income when earned. ​ Past Due and Nonaccrual Loans ​ Loans are considered past due or delinquent when the contractual principal or interest due in accordance with the terms of the loan agreement or any portion thereof remains unpaid after the due date of the scheduled payment. Generally, loans are placed on nonaccrual status (i) when either principal or interest payments become 90 days or more past due based on contractual terms unless the loan is sufficiently collateralized such that full repayment of both principal and interest is expected and is in the process of collection within a reasonable period or (ii) when an individual analysis of a borrower’s creditworthiness indicates a credit should be placed on nonaccrual status whether or not the loan is 90 days or more past due. When a loan is placed on nonaccrual status, unpaid interest credited to income is reversed. Interest received on such loans is accounted for on the cash-basis or cost recovery method, until qualifying for return to accrual. Under the cost-recovery method, interest income is not recognized until the loan balance is reduced to zero. Under the cash basis method, interest income is recorded when the payment is received in cash. Nonaccrual loans are returned to accrual status when the financial position of the borrower and other relevant factors indicate there is no longer doubt that the Company will collect all principal and interest due. ​ ​ ​ Purchase Credit Deteriorated (PCD) Loans ​ Purchased credit deteriorated loans (“PCD loans”) are purchased loans, that, as of the date of acquisition, have experienced a more-than-insignificant deterioration in credit quality since origination, as determined by the Company’s assessment. An allowance for credit losses is determined using the same methodology as other loans held for investment. The initial allowance for credit losses determined on an individual loan basis from an evaluation of each specific loan and its related credit metrics. The sum of the loan’s purchase price and initial allowance for credit losses becomes its initial amortized cost basis. The difference between the initial amortized cost basis and the par value of the loan is a noncredit discount or premium, which is accreted or amortized into interest income over the life of the loan. Expected cash flows in excess of the amount paid are recorded as interest income over the remaining life of the loans (accretable yield). The excess of the loan’s contractual principal and interest over expected cash flows is not recorded (nonaccretable difference). ​ Subsequent changes to the allowance for credit losses are recorded through provision for credit losses. Over the life of the loan, expected cash flows continue to be estimated. If the present value of expected cash flows is less than the carrying amount, a loss is recorded as a provision for credit losses. If the present value of expected cash flows is greater than the carrying value, it is recognized as part of future interest income. ​ Non-Purchase Credit Deteriorated (Non-PCD) Loans ​ Non-purchased credit deteriorated loans (“non-PCD loans”) are purchased loans, that, as of the date of acquisition, have not experienced a significant deterioration in credit quality since origination, as determined by the Company’s assessment. An allowance for credit losses is determined using the same methodology as other loans held for investment, and no allowance is established as a Day One fair valuation allowance. The sum of the loan’s purchase price net of any related credit and interest rate premium or discount becomes its initial amortized cost basis. The difference between the initial amortized cost basis and the par value of the loan is a discount or premium, which is comprised of an interest component and a credit component, and is accreted or amortized into interest income over the life of the loan. Expected cash flows in excess of the amount paid are recorded as interest income over the remaining life of the loans (accretable yield). The excess of the loan’s contractual principal and interest over expected cash flows is not recorded (nonaccretable difference). ​ A subsequent Day Two adjustment on non-PCD loans is recorded to the allowance for credit losses immediately after acquisition, which reflects the future estimated lifetime credit losses on the non-PCD loans, recorded through the provision for credit losses. Over the life of the loan, expected cash flows continue to be estimated. If the present value of expected cash flows is less than the carrying amount, a loss is recorded as a provision for credit losses. If the present value of expected cash flows is greater than the carrying value, it is recognized as part of future interest income.
Allowance for Credit Losses ("ACL") | Allowance for Credit Losses (“ACL”) ​ ACL on Loans ​ The ACL on loans is a valuation account that is deducted from the amortized cost basis of loans to present the net amount expected to be collected on loans. The Company’s estimate of the ACL for loans reflects losses expected over the remaining contractual life of the loans. The contractual term does not consider extensions, renewals or modifications. ​ Determination of the ACL on loans is inherently subjective in nature since it requires significant estimates and management judgment, and includes a level of imprecision given the difficulty of identifying and assessing the factors impacting loan repayment and estimating the timing and amount of losses. While management utilizes its best judgment and information available, the ultimate adequacy of the ACL is dependent upon a variety of factors beyond the Company’s direct control, including, but not limited to, the performance of the loan portfolio, consideration of current economic trends, changes in interest rates and property values, estimated losses on pools of homogeneous loans based on an analysis that uses historical loss experience for prior periods that are determined to have like characteristics with the current period such as pre-recessionary, recessionary, or recovery periods, portfolio growth and concentration risk, management and staffing changes, the interpretation of loan risk classifications by regulatory authorities and other credit market factors. While each component of the ACL on loans is determined separately, the entire balance is available for the entire loan portfolio. ​ The ACL methodology consists of measuring loans on a collective (pool) basis when similar risk characteristics exist. The type of credit composition and risk characteristics of each portfolio segment are as follows:
Lease financing receivables | Lease financing receivables – Lease financing receivables are subject to underwriting standards and processes similar to commercial loans. These loans are often secured by equipment or transportation assets, and are made based primarily on the historical and projected cash flow of the borrower and secondarily on the underlying collateral provided by the borrower. The cash flows of borrowers, however, may not behave as forecasted and collateral securing loans may fluctuate in value due to economic or individual performance factors. The Company’s historical loss rates are utilized from the prior periods which align to the current unemployment projections for the next twelve months.
Premises and Equipment | Premises and Equipment – Premises, furniture, equipment, and leasehold improvements are stated at cost less accumulated depreciation and amortization. Depreciation expense is determined by the straight-line method over the estimated useful lives of the assets. Leasehold improvements are amortized on a straight-line basis over the shorter of the life of the asset or the lease term including anticipated renewals. Rates of depreciation are generally based on the following useful lives: buildings, 25 to 40 years; building improvements, 3 to 15 years or longer under limited circumstances; and furniture and equipment, 3 to 10 years. Fixed Assets Held for Sale totaling $1.4 million are reported within other assets in the Consolidated Balance Sheets. Gains and losses on dispositions are included in other noninterest expense in the Consolidated Statements of Income. Maintenance and repairs are charged to operating expenses as incurred, while improvements that conform to definitions of tangible property improvements are capitalized and depreciated over the estimated remaining life. ​ Whenever events or changes in circumstances dictate, the Company tests its long-lived assets for impairment by determining whether the sum of the estimated undiscounted future cash flows attributable to a long-lived asset or asset group is less than the carrying value of the long-lived asset or asset group through a probability-weighted approach. In the event the carrying amount of the long-lived asset or asset group is not recoverable, an impairment loss is measured as the amount by which the carrying amount of the long-lived asset or asset group exceeds its fair value. ​ ​ All of the Company’s leases are classified as operating leases at inception. The Company leases certain branch locations and equipment; leased equipment is primarily Automated Teller Machines (ATMs). The Company records leases on the balance sheet in the form of a lease liability at the present value of future minimum payments under the terms of the lease and as a right-of-use asset equal to the lease liability adjusted for items such as deferred or prepaid rent, lease incentives, and any impairment of the right-of-use asset if it should arise. The discount rate used in determining the lease liability is based on the incremental borrowing rates the Company could obtain for similar loans as of the date of the commencement or renewal. The Company does not record short-term leases with an initial lease term of one year or less on the Consolidated Balance Sheets. ​ At lease inception, the Company determines the lease term by considering the noncancelable lease term and all option renewal periods the Company deems reasonably certain to renew. The lease term is also used to calculate the straight-line basis. Leasehold improvements are amortized over the shorter of the useful life or the estimated lease term. ​ Operating lease expense consists of a single lease cost allocated over the remaining lease term on a straight-line basis, and any impairment of the right-of-use asset. Lease expense is included in occupancy, furniture, and equipment on the Company’s Consolidated Statements of Income. The Company’s variable lease expense includes items such as common area maintenance, utilities, parking, and property taxes, which are reported within occupancy, furniture, and equipment on the Consolidated Statements of Income.
Other Real Estate Owned ("OREO") | Other Real Estate Owned (“OREO”) – Real estate assets acquired in settlement of loans are recorded at the fair value of the property when acquired, less estimated costs to sell, establishing a new cost basis. Physical possession of residential real estate property collateralizing a consumer mortgage loan occurs when legal title is obtained upon foreclosure or when the borrower conveys all interest in the property to satisfy the loan through completion of a deed in lieu of foreclosure or through a similar legal agreement. Any deficiency between the net book value and fair value at the foreclosure or deed in lieu date is charged to the ACL. Any reduction in OREO carrying value within 90 days of transfer to OREO would be charged to the ACL. If the fair value of the property when acquired, less estimated costs to sell, is greater than the net book value of the loan, a gain on transfer is recorded. If a determination is made more than 90 days after the transfer to OREO that the fair value for the OREO property has declined, an OREO valuation allowance is established for the decrease between the recorded value and the updated fair value less costs to sell. Such declines are included in other noninterest expense in the Consolidated Statements of Income. A subsequent reversal of an OREO valuation adjustment can occur, but the resultant carrying value cannot exceed the cost basis established at transfer of the loan to OREO. Operating costs after acquisition are also expensed. ​
Mortgage Servicing Rights ("MSRs") | Mortgage Servicing Rights (“MSRs”) – The Bank is also involved in the business of servicing mortgage loans. Servicing activities include collecting principal, interest, and escrow payments from borrowers, making tax and insurance payments on behalf of the borrowers, monitoring delinquencies, executing foreclosure proceedings, and accounting for and remitting principal and interest payments to the investors. MSRs represent the right to a stream of cash flows and an obligation to perform specified residential mortgage servicing activities. ​ Mortgage loans that the Company is servicing for others aggregated to $709.1 million and $737.2 million at December 31, 2024, and 2023, respectively. Mortgage loans that the Company is servicing for others are not included in the Consolidated Balance Sheets. Fees received in connection with servicing loans for others are recognized as earned. Loan servicing costs are charged to expense as incurred. ​ Servicing rights are recognized separately as assets when they are acquired through sales of loans and servicing rights are retained. Servicing rights are initially recorded at fair value with the effect recorded in net gains on sales of mortgage loans in the Consolidated Statements of Income. Fair value is based on market prices for comparable mortgage servicing contracts, when available, or alternatively, is based on a valuation model that calculates the present value of estimated future net servicing income. The valuation model incorporates assumptions that market participants would use in estimating future net servicing income, such as the cost to service, the discount rate, the custodial earnings rate, an inflation rate, ancillary income, prepayment speeds and default rates and losses. ​ Servicing fee income, which is included in the Consolidated Statements of Income as mortgage servicing income, is recorded for fees earned for servicing loans. The fees are based on a contractual percentage of the outstanding principal or a fixed amount per loan and are recorded as income when earned. ​ Under the fair value measurement method, the Company measures mortgage servicing rights at fair value at each reporting date, reports changes in fair value of servicing assets in earnings in the period in which the changes occur, and includes these changes in MSRs mark to market values in the Consolidated Statements of Income. The fair values of MSRs are subject to significant fluctuations as a result of interest rates, changes in estimated and actual prepayment speeds and default rates and losses. ​ ​ ​ Transfers of Financial Assets – The Company accounts for transfers and servicing of financial assets in accordance with FASB ASC 860, Transfers and Servicing. Transfers of financial assets are accounted for as sales only when control over the assets has been surrendered. Control over transferred assets is deemed to be surrendered when (1) the assets have been isolated from the Company, (2) the transferee obtains the right (free from conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets and (3) the Company does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity. ​ Transfers of a portion of a loan must meet the criteria of a participating interest. If it does not meet the criteria of a participating interest, the transfer must be accounted for as a secured borrowing. In order to meet the criteria for a participating interest, all cash flows from the loan must be divided proportionately, the rights of each loan holder must have the same priority, and the loan holders must have no recourse to the transferor other than standard representations and warranties and no loan holder has the right to pledge or exchange the entire loan. ​ The Company sells financial assets in the normal course of business, the majority of which are related to residential mortgage loan sales through established programs, and commercial loan sales through participation agreements. In accordance with accounting guidance for asset transfers, the Company considers any ongoing involvement with transferred assets in determining whether the assets can be derecognized from the balance sheet. With the exception of servicing and certain performance-based guarantees, the Company’s continuing involvement with financial assets sold is minimal and generally limited to market customary representation and warranty clauses. ​ When the Company sells financial assets, it may retain servicing rights and/or other interests in the financial assets. The gain or loss on sale depends on the previous carrying amount of the transferred financial assets, the servicing right recognized, the consideration received, and any liabilities incurred in exchange for the transferred assets. Upon transfer, any servicing assets and other interests held by the Company are carried at the lower of cost or fair value, with the exception of mortgage servicing rights related to sales of residential mortgage loans, which are carried at fair value.
Bank-Owned Life Insurance ("BOLI") | Bank-Owned Life Insurance (“BOLI”) – BOLI represents life insurance policies on the lives of certain Company employees (both current and former) for which the Company is the sole owner and beneficiary. These policies are recorded as an asset on the Consolidated Balance Sheets at their cash surrender value (“CSV”) or the amount that could be realized upon immediate liquidation. The change in CSV is recorded as an increase in cash surrender value of BOLI in the Consolidated Statements of Income in noninterest income. In addition, insurance proceeds received, net of the original premium investment, are recorded as death benefit realized on BOLI in the Consolidated Statements of Income in noninterest income.
Goodwill and Core Deposit Intangible | Goodwill and Core Deposit Intangible – Goodwill is the excess of an acquisition’s purchase price over the fair value of identified net assets acquired in an acquisition and is evaluated at least annually for impairment. The Company performs its annual evaluation for goodwill impairment at November 30 each year and may elect to perform a quantitative or qualitative analysis or first conduct a qualitative analysis to determine if a quantitative analysis is necessary. In addition, the Company evaluates goodwill impairment on an interim basis if events or changes in circumstances indicate the asset might be impaired. The factors reviewed by the Company when completing a qualitative analysis include, but are not limited to, macroeconomic data, industry specific data, current market conditions, and the Company’s overall financial performance. ​ The Company performed a qualitative assessment of goodwill as of November 30, 2024 which resulted in the fair value of the Company exceeding the carrying value; therefore, it was determined goodwill was not impaired at December 31, 2024. On November 30, 2023, the Company performed a qualitative assessment of goodwill from which we concluded it was more likely than not that goodwill was not impaired as of December 31, 2023. A quantitative assessment is performed every third year as a matter of periodic practice rather than as a response to a qualitative assessment or triggering event. ​ The core deposit intangible (“CDI”) is being amortized on an accelerated method over a ten year estimated useful life. As of December 31, 2024, CDI totaled $22.0 million compared to $11.2 million at December 31, 2023. The total CDI amount reflects the transaction with First Merchants Bank in 2024, the acquisition of West Suburban in 2021 as well as ABC Bank in 2018, and the Talmer Bank branch purchase in 2016. Total CDI amortization expense of $2.4 million, $2.5 million, and $2.6 million was recorded in 2024, 2023, and 2022, respectively. The expected future annual amortization expense for each of the next five years (2025-2029) is approximately $4.1 million, $3.7 million, $3.3 million, $2.9 million, and $2.6 million, respectively.
Debt Issuance Costs | Debt Issuance Costs – Costs associated with the issuance of debt are presented in the Consolidated Balance Sheets as a direct reduction from the carrying value of that debt liability. The deferred issuance costs are amortized over the life of the related debt instrument, and included within the debt’s interest expense.
Loss Contingencies | Loss Contingencies – Loss contingencies, including claims and legal actions arising in the ordinary course of business, are recorded as liabilities when the likelihood of loss is probable and an amount or range of loss can be reasonably estimated. Management does not believe there are such matters that will have a material effect on the financial statements.
Noninterest Income | Noninterest Income – The Company recognizes revenue when the performance obligations related to the transfer of goods or services are satisfied. Certain obligations are satisfied at one point in time, while other obligations may be satisfied over a period of time. Revenues are segregated based on the nature of the product or service offered. Wealth management fees, service charges on deposits and card related income are included as components of noninterest income in the Consolidated Statements of Income. ​ Wealth management – includes fees generated from personal, commercial and institutional clients. The Company also provides asset management services, cash management services and income tax reporting. Revenue is recognized over the period of time in which these services are performed. ​ Service charges on deposits – includes fees and income received by the Company for performing various services, such as deposit account maintenance fees, overdraft coverage and processing fees, stop payment charges, and other deposit account related services. Revenue is recognized based on the service agreement in place, and is recorded when the service is provided to the customer. This item is net of any service charge refunds or return charge refunds. ​ Card related income – includes interchange fees earned on debit cards and credit cards, ATM/ITM related fee income, and gift card related income. Annual fees and interest income on card-related products are recognized within interest income in accordance with ASC 310. The Company recognizes card related income when the cardholder’s transaction with the merchant or ATM/ITM occurs, thus satisfying the performance obligation. Card related expenses, such as disbursements to the payment network, reward program costs, and other operational costs are carried within card related expense, as a component of noninterest expense, on the Consolidated Statements of Income.
Advertising Costs | ​ Advertising Costs – All advertising costs incurred by the Company are expensed in the period in which they are incurred.
Equity Incentive Plan | Equity Incentive Plan – Compensation cost is recognized for stock options and restricted stock awards issued to employees based upon the fair value of the awards at the date of grant. A binomial model is utilized to estimate the fair value of stock options, which utilizes assumptions for expected volatilities based on the previous five-year historical volatilities of the Company's common stock. Historical data is used to estimate option exercise rates and post-vesting termination behavior, and the risk-free interest rate for the expected term of the option is based on the Treasury yield curve in effect at the time of grant. The market price of the Company’s common stock at the date of grant is used for restricted stock awards, which include restricted stock units. Compensation cost is recognized over the required service period, generally defined as the vesting period, and is net of a 5% forfeiture assumption for group grants. Upon vesting, compensation costs for the award expense is trued up based on actual forfeitures incurred. Once the award is settled, the Company would determine whether the cumulative tax deduction exceeded the cumulative compensation cost recognized in the Consolidated Statements of Income. The cumulative tax deduction would include both the deductions from the dividends and the deduction from the exercise or vesting of the award. If the tax benefit received from the cumulative deductions exceeds the tax effect of the recognized cumulative compensation cost, the excess would be recognized as a credit to income tax expense.
Income Taxes | Income Taxes – The Company files income tax returns in the U.S. federal jurisdiction, and in the states of Illinois, Arizona, California, Florida, Indiana, Michigan, New Hampshire, Ohio, Pennsylvania, Tennessee, Texas, and Wisconsin. The provision for income taxes is based on income in the consolidated financial statements, rather than amounts reported on the Company’s income tax return. Income tax expense is the total of the current year income tax due or refundable and the change in deferred tax assets and liabilities. Any change in tax rates will be recorded in the period in which the law is enacted. ​ Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using the enacted tax rates that are expected to apply to taxable income in years in which those temporary differences are expected to be recovered or settled. ​ As of December 31, 2024 and 2023, the Company evaluated tax positions taken for filings with the Internal Revenue Service and all state jurisdictions in which it operates. The Company believes that income tax filing positions will be sustained under examination and does not anticipate any adjustments that would result in a material adverse effect on the Company’s financial condition, results of operations, or cash flows. Accordingly, the Company has not recorded any material reserves or related accruals for interest and penalties for uncertain tax positions at December 31, 2024 and 2023. The Company is no longer subject to examination by the Internal Revenue Service for tax years prior to 2021. State statutes vary, but generally, the Company is no longer subject to state tax examinations for tax years ended prior to 2020.
Earnings Per Common Share ("EPS") | Earnings Per Common Share (“EPS”) – Basic EPS is computed by dividing net income applicable to common stockholders by the weighted-average number of common shares outstanding for the period. Diluted EPS is computed by dividing net income applicable to common stockholders by the weighted-average number of common shares outstanding plus the number of additional common shares that would have been outstanding if the dilutive potential shares had been issued. The Company’s potential common shares represent shares issuable under its long-term incentive compensation plans.
Treasury Stock | ​ Treasury Stock – Treasury stock acquired is recorded at cost and is carried as a reduction of stockholders’ equity in the Consolidated Balance Sheets. Treasury stock issued is valued based on the “last in, first out” inventory method. The difference between the consideration received upon issuance and the carrying value is charged or credited to additional paid-in capital.
Derivative Financial Instruments | Derivative Financial Instruments – The Company occasionally enters into derivative financial instruments as part of its interest rate risk management strategies. These derivative financial instruments consist primarily of interest rate swaps. The Company records all derivatives on the balance sheet at fair value. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative and whether the Company has elected to designate a derivative as a hedging relationship and apply hedge accounting. A further consideration involves a determination on whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. Derivatives designated and qualifying as a hedge of the exposure to changes in the fair value of an asset, liability, or firm commitment attributable to a particular risk, such as interest rate risk, are considered fair value hedges. Hedge accounting generally provides for the matching of the timing of gain or loss recognition on the hedging instrument with the recognition of the changes in the fair value of the hedged asset or liability that are attributable to the hedged risk in a fair value hedge or the earnings effect of the hedged forecasted transactions in a cash flow hedge. The Company may enter into derivative contracts that are intended to economically hedge certain risks, even though hedge accounting does not apply or the Company elects not to apply hedge accounting. ​ If it is determined that the derivative instrument is not highly effective as a hedge, hedge accounting is discontinued, and the adjustment to fair value of the derivative instrument is recorded in earnings. For a derivative used to hedge changes in cash flows associated with forecasted transactions, the gain or loss on the effective portion of the derivative is deferred and reported as a component of accumulated other comprehensive income, which is a component of stockholders’ equity, until such time the hedged transaction affects earnings. For derivative instruments not accounted for as hedges, changes in fair value are recognized in noninterest income/expense. Counterparty risk with loan customers is managed through loan covenant agreements and, as such, does not have a significant impact on the fair value of the swaps. Counterparty risk with other banks is managed through bilateral collateralization agreements. Deferred gains and losses from derivatives not accounted for as hedges and that are terminated are amortized over the shorter of the original remaining term of the derivative or the remaining life of the underlying asset or liability.
Comprehensive Income | Comprehensive Income – Comprehensive income is the total of reported earnings for all other revenues, expenses, gains, and losses that are not reported in earnings under GAAP. The Company includes the following items, net of tax, in other comprehensive income in the Consolidated Statements of Comprehensive Income (Loss): (i) changes in unrealized gains or losses on securities available-for-sale, and (ii) the effective portion of a derivative used to hedge cash flows.
Recent Accounting Pronouncements | Recent Accounting Pronouncements – The following is a summary of recent accounting pronouncements that have impacted or could potentially affect the Company: ​ ASU 2023-06 – On October 9, 2023, the FASB issued ASU 2023-06 “Disclosure Improvements: Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative”. The amendments in the ASU modify the disclosure or presentation requirements of a variety of topics in the codification. Certain of the amendments represent clarifications to, or technical corrections of, the current requirements. Each amendment in the ASU will only become effective if the SEC removes the related disclosure or presentation requirement from its existing regulations by June 30, 2027. The amendments in this ASU are not expected to have a material impact on the financial statements of the Company. ​ ASU 2023-09 – On December 14, 2023, the FASB issued ASU 2023-09 “Income Taxes (Topic 740): Improvements to Income Tax Disclosures”. The amendments require that public business entities on an annual basis (1) disclose specific categories in the rate reconciliation, and (2) provide additional information for reconciling items that meet a quantitative threshold (if the effect of those reconciling items is equal to or greater than 5 percent of the amount computed by multiplying pretax income (or loss) by the applicable statutory income tax rate). The amendments require that all entities disclose on an annual basis the following information about income taxes paid: (1) The amount of income taxes paid (net of refunds received) disaggregated by federal (national), state, and foreign taxes, and (2) The amount of income taxes paid (net of refunds received) disaggregated by individual jurisdictions in which income taxes paid (net of refunds received) is equal to or greater than 5 percent of total income taxes paid (net of refunds received). The amendments also require that all entities disclose the following information: (1) Income (or loss) from continuing operations before income tax expense (or benefit) disaggregated between domestic and foreign, and (2) Income tax expense (or benefit) from continuing operations disaggregated by federal (national), state, and foreign. The ASU is effective for public business entities for annual periods beginning after December 15, 2024. Early adoption is permitted for annual financial statements that have not yet been issued or made available for issuance. The amendments should be applied on a prospective basis. Retrospective application is permitted. The Company will adopt this ASU for the reporting period beginning January 1, 2025, and does not expect the amendments to have a material impact to the financial statements of the Company. ​ ​ ASU 2024-01 – On March 21, 2024, the FASB issued ASU 2024-01 “Compensation - Stock Compensation (Topic 718) - Scope Application of Profits Interest and Similar Awards”, which clarifies how an entity determines whether a profits interest or similar award is within the scope of Topic 718 or is not a share-based payment arrangement and, therefore is within the scope of other guidance. ASU 2024-01 provides an illustrative example with multiple fact patterns and also amends certain language in the “Scope” and “Scope Exceptions” sections of Topic 718 to improve its clarity and operability without changing the guidance. Entities can apply the amendments either retrospectively to all prior periods presented in the financial statements or prospectively to profits interest and similar awards granted or modified on or after the date of adoption. If prospective application is elected, an entity must disclose the nature of and reason for the change in accounting principle. ASU 2024-01 was effective January 1, 2025, including interim periods, and is not expected to have a material impact on the financial statements of the Company. ​ ASU 2024-02 – On March 29, 2024, the FASB issued ASU 2024-02 “Codification Improvements – Amendments to Remove References to the Concepts Statements”, which amends the codification to remove references to various concept statements and impacts a variety of topics in the codification. The amendments apply to all reporting entities within the scope of the affected accounting guidance, but in most instances the references removed are extraneous and not required to understand or apply the guidance. Generally, the amendments in ASU 2024-02 are not intended to result in significant accounting changes for most entities. ASU 2024-02 was effective January 1, 2025, and is not expected to have a material impact the financial statements of the Company. ​ ASU 2024-03 – On November 4, 2024, the FASB issued ASU 2024-03 “Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses”. This ASU requires public companies to disclose, in the notes to financial statements, specified information about certain costs and expenses at each interim and annual reporting period. Specifically, they will be required to: (1) Disclose the amounts of (a) purchases of inventory; (b) employee compensation; (c) depreciation; (d) intangible asset amortization; and (e) depreciation, depletion, and amortization recognized as part of oil- and gas-producing activities (or other amounts of depletion expense) included in each relevant expense caption. Include certain amounts that are already required to be disclosed under current generally accepted accounting principles (GAAP) in the same disclosure as the other disaggregation requirements. (2) Disclose a qualitative description of the amounts remaining in relevant expense captions that are not separately disaggregated quantitatively. (3) Disclose the total amount of selling expenses and, in annual reporting periods, an entity’s definition of selling expenses. ASU 2024-03 is effective for public business entities for annual reporting periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027, and is not expected to have a material impact on the financial statements of the Company.
Subsequent Events | Subsequent Events ​ On January 21, 2025, the Company’s Board of Directors declared a cash dividend of $0.06 per share payable on February 10, 2025, to stockholders of record as of January 31, 2025. On February 24, 2025, Old Second and Bancorp Financial, Inc. (“Bancorp Financial”) entered into an Agreement and Plan of Merger (the “merger agreement”). The merger agreement provides that, upon the terms and subject to the conditions set forth therein, Bancorp Financial will merge with and into Old Second, with Old Second continuing as the surviving entity (the “merger”). Immediately following the merger, Evergreen Bank Group (“Evergreen Bank”), an Illinois state-chartered bank and wholly-owned subsidiary of Bancorp Financial, will merge with and into Old Second National Bank, a national banking association and wholly-owned subsidiary of Old Second, with Old Second National Bank continuing as the surviving bank (the “bank merger”). ​ Subject to the terms and conditions of the merger agreement, at the effective time of the merger, each Bancorp Financial stockholder will receive 2.5814 shares of Old Second common stock and $15.93 in cash for each share of Bancorp Financial common stock owned by the stockholder. Holders of Bancorp Financial common stock, subject to certain exceptions, will also be entitled to receive cash in lieu of fractional shares of Old Second common stock. ​ The parties to the merger expect to complete the merger in the third quarter of 2025, subject to satisfaction of closing conditions, including receipt of customary required regulatory approvals and the approval of the merger agreement by the Bancorp Financial stockholders.
Mortgage Banking Derivatives. |
Summary of Significant Accounting Policies |
Derivative Financial Instruments | Mortgage Banking Derivatives – As part of the ongoing residential mortgage business, the Company enters into mortgage banking derivatives such as forward contracts and interest rate lock commitments. The derivatives and loans held-for-sale are carried at fair value with the changes in fair value recorded in current earnings. The net gain or loss on mortgage banking derivatives is included in net gains on sales of loans in the Consolidated Statements of Income.
Commercial |
Summary of Significant Accounting Policies |
Loans | Commercial loans – Such credits typically comprise working capital loans, loans for physical asset expansion, asset acquisition loans and other commercial and industrial business loans. Loans to closely held businesses will generally be guaranteed in full or for a meaningful amount by the businesses’ major owners. Commercial loans are made based primarily on the historical and projected cash flow of the borrower and secondarily on the underlying collateral provided by the borrower. The cash flows of borrowers, however, may not behave as forecasted and collateral securing loans may fluctuate in value due to economic or individual performance factors. Minimum standards and underwriting guidelines have been established for all commercial loan types. The Company classifies five different risk levels for this segment to assign a loss rate based on historical losses, and may utilize qualitative overlays to align historical loss experience with expectations during the forecast period.
Real estate - commercial loans |
Summary of Significant Accounting Policies |
Loans | Real estate - commercial loans – Real estate - commercial loans are subject to underwriting standards and processes similar to commercial and industrial loans. These are loans secured by mortgages on real estate collateral. Commercial real estate loans are viewed primarily as cash flow loans and the repayment of these loans is largely dependent on the successful operation of the property. Loan performance may be adversely affected by factors impacting the general economy or conditions specific to the real estate market, such as geographic location and/or property type. The real estate – commercial segments utilized for the ACL on loans are:
| ● | CRE owner occupied – the Company classifies five different risk levels within this segment to assign a loss rate based on historical losses, as well as utilizing a forecasted average unemployment rate and Gross Domestic Product (“GDP”) for the next twelve months as a loss driver.
| ● | CRE investor – the Company classifies five different risk levels within this segment to assign a loss rate based on historical losses, as well as utilizing a forecasted average unemployment rate and GDP for the next twelve months as a loss driver. The primary difference between this segment and CRE owner occupied is within the slightly elevated historical loss rates.
Real estate - residential loans |
Summary of Significant Accounting Policies |
Loans | Real estate - residential loans – These are loans that are extended to purchase or refinance family residential dwellings. Residential real estate loans are considered homogenous in nature. Homes may be the primary or secondary residence of the borrower or may be investment properties of the borrower. The real estate – residential segments utilized for the ACL on loans are:
| ● | Residential owner-occupied – these loans are secured by 1-4 family residential dwellings that are primary or secondary residences and the Company holds a first lien position. The Company applies historical loss rates from periods with like characteristics as the current period, with a longer remaining life than other segments, due to the often longer-term nature of these loans.
| ● | Residential investor – these loans are secured by 1-4 family residential dwellings that are not a primary or secondary residence and the Company holds a first lien position. The Company applies historical loss rates from periods with like characteristics as the current period, with a slightly longer remaining life than other segments, but shorter duration than residential owner-occupied.
| ● | Multifamily – these loans are secured by 5+ unit residential dwellings and the Company typically holds a first lien position. The Company classifies five different risk levels within this segment to assign a loss rate based on historical losses, as well as utilizing a forecasted average unemployment rate and GDP for the next twelve months as a loss driver.
Consumer |
Summary of Significant Accounting Policies |
Loans | Home equity lines of credit (“HELOCs”) – These are lines of credit that are extended to refinance 1-4 family residential dwellings, or to finance the borrower’s needs and collateralized by the borrower’s residence. These lines may be fixed or variable in nature, and the home serving as collateral may also have a first lien outstanding. The Company’s historical loss rates are utilized from the prior periods which align to the current unemployment projections for the next twelve months. ​ Consumer loans – Consumer loans include loans extended primarily for consumer and household purposes. These also include overdrafts and other items not captured by the definitions above. The primary loss driver for this segment is the unemployment rate forecast for the next twelve months. ​ The methodologies used for calculating the ACL on each loan segment include (i) a migration analysis for commercial, CRE owner occupied, CRE investor, and multifamily segments; (ii) a static pool analysis for construction, leases, residential investor, residential owner occupied and the HELOC segments; and (iii) a WARM (weighted average remaining maturity) methodology is used for consumer segments. The forecast period used for each segment calculation was one year, with an immediate reversion to historical loss rates following this one year period. In addition, the Company applies qualitative adjustments to each different loan, as described below. ​ ​ ​ The qualitative factors applied to each loan portfolio consist of the impact of other internal and external qualitative and credit market factors as assessed by management through a detailed loan review, ACL analysis and credit discussions. These internal and external qualitative and credit market factors include:
| ● | changes in lending policies and procedures, including changes in underwriting standards and collections, charge-offs and recovery practices;
| ● | changes in international, national, regional, and local conditions (specific factors which impact portfolios or discrepancies with national economic factors which are utilized within the economic forecast);
| ● | changes in the experience, depth and ability of lending management;
| ● | changes in the volume and severity of past due loans and other similar loan conditions;
| ● | changes in the nature and volume of the loan portfolio and terms of loans;
| ● | the existence and effect of any concentrations of credit and changes in the levels of such concentrations (this characteristic requires any portfolio exceeding 25% of capital to have a factor considered unless the pool is otherwise well diversified or holds a relatively low inherent risk);
| ● | effects of other external factors, such as competition, legal or regulatory factors, on the level of estimated credit losses;
| ● | changes in the quality of our loan review functions; and
| ● | changes in the value of underlying collateral for collateral dependent loans.
​ The impact of the above listed internal and external qualitative and credit market risk factors is assessed within predetermined ranges to adjust the ACL totals calculated. Changes in the above factors are assessed no less than quarterly, and directly impact the total estimated credit losses recorded. ​ Loans that do not share risk characteristics are evaluated on an individual basis. Such loans evaluated individually are not also included in the collective evaluation. The amount of expected credit loss is measured based upon the present value of expected future cash flows discounted at the loan’s effective interest rate or the fair value of the underlying collateral less applicable selling costs. When management determines that foreclosure is probable, the amount of credit loss is determined using the fair value of collateral, less costs to sell. ​ Loans are charged off against the ACL when management believes the uncollectibility of a loan balance is confirmed, while recoveries of amounts previously charged-off are credited to the ACL. Expected recoveries do not exceed the aggregate of amounts previously charged-off and expected to be charged off. Approved releases from previously established ACL reserves authorized under our ACL methodology also reduce the ACL. Additions to the ACL are established through the provision for credit losses on loans, which is charged to expense. The Company’s ACL methodology is intended to reflect all loan portfolio risk, but management recognizes the inability to accurately depict all future credit losses in a current ACL estimate, as the impact of various factors cannot be fully known. Accrued interest receivable on loans is excluded from the amortized cost basis of financing receivables for the purpose of determining the allowance for credit losses. ​ ACL on Unfunded Loan Commitments ​ The Company estimates expected credit losses over the contractual period in which the Company is exposed to credit risk by a contractual obligation to extend credit, unless that obligation is unconditionally cancellable by the Company. The ACL related to off-balance sheet credit exposures, which is within other liabilities on the Company’s Consolidated Balance Sheets, is estimated at each balance sheet date under the CECL model, and is adjusted as determined necessary through the provision for credit losses on the income statement. The estimate for ACL on unfunded loan commitments includes consideration of the likelihood that funding will occur and an estimate of expected credit losses on commitments expected to be funded over its estimated life.
Real estate - construction | Real estate - commercial loans |
Summary of Significant Accounting Policies |
Loans | Real estate - construction loans – The Company defines real estate - construction loans as loans where the loan proceeds are controlled by the Company and used exclusively for the improvement or development of real estate in which the Company holds a mortgage. Due to the inherent risk in this type of loan, they are subject to other industry specific policy guidelines outlined in the Company’s Credit Risk Policy and are monitored closely. The Company’s historical loss rates are utilized from the prior periods which align to the current unemployment projections for the next twelve months.

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