Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2026
Summary of Significant Accounting Policies
Loans	Loans Loans that management has originated and has the intent and ability to hold for the foreseeable future or until maturity or pay off generally are reported at their unpaid principal balances, less unearned income and net of any deferred loan fees and costs, including unamortized fair value discount or premium. Unearned income on installment loans is recognized as income over the terms of the loans by methods that generally approximate the interest method. Interest on other loans is calculated by using the simple interest method on daily balances of the principal amount outstanding. If the loan is prepaid, the remaining unamortized fees and costs are charged or credited to interest income. Amortization ceases for non-accrual loans. We place loans on nonaccrual once reasonable doubt exists about the collectability of all principal and interest due. Generally, this occurs when principal or interest is 90 days or more past due, unless the loan is well secured and in the process of collection and excludes factored receivables. For factored receivables, which are commercial trade credits rather than promissory notes, the Company’s practice, in most cases, is to charge-off unpaid recourse receivables when they become 240 days past due from the invoice due date and the non-recourse receivables when they become 240 days past due from the statement due date. Past due status is based on the contractual terms of the loan. In all cases, loans are placed on non-accrual or charged-off at an earlier date if collection of principal or interest is considered doubtful.
Allowance for Credit Losses ("ACL")	Allowance for Credit Losses (“ACL”) – Investment Securities Management monitors the held to maturity securities portfolio to determine whether a valuation account should be recorded. Management evaluates impairment where there has been a decline in fair value below the amortized cost basis of a security to determine whether there is a credit loss associated with the decline in fair value at least quarterly, and more frequently when economic or market concerns warrant such evaluation. The Company’s methodology on how the ACL is calculated is disclosed in Note 1 — Summary of Significant Accounting Policies, under the “ACL – Investment Securities” section, of our Annual Report for the year ended December 31, 2025. As of March 31, 2026 and December 31, 2025, the Company had $2.0 billion of held to maturity securities and no related valuation account. The Company follows its nonaccrual policy by reversing interest income in the income statement when the Company determines the interest for held to maturity securities is uncollectible. Therefore, management excludes the accrued interest receivable balance from the amortized cost basis in measuring expected credit losses on the investment securities and does not record an allowance for credit losses on accrued interest receivable. As of March 31, 2026 and December 31, 2025, the accrued interest receivables for all investment securities recorded in Other Assets were $42.0 million and $38.9 million, respectively. ACL – Loans and Certain Off-Balance-Sheet Credit Exposures The ACL for loans held for investment reflects management’s estimate of credit losses that will result from the inability of our borrowers to make required loan payments. The Company makes adjustments to the ACL by recording a provision for or recovery of credit losses through earnings. Loans charged off are recorded as reductions to the ACL on the balance sheet and subsequent recoveries of loan charge-offs are recorded as increases to the ACL when they are received. Management estimates the allowance balance using relevant available information, from internal and external sources, relating to past events, current conditions, and reasonable and supportable forecasts. Historical credit loss experience provides the basis for the estimation of expected credit losses. Adjustments to historical loss information are made for differences in current loan-specific risk characteristics such as differences in underwriting standards, portfolio mix, credit quality, or term, as well as for changes in macroeconomic conditions, such as changes in unemployment rates, gross domestic product, property values, or other relevant factors. Acquired portfolios may be supported by separate credit models using loss histories relevant to those portfolios. The Company’s estimate of its ACL involves a high degree of judgment; therefore, management’s process for determining expected losses may result in a range of expected losses. The Company’s ACL recorded in the balance sheet reflects management’s best estimate within the range of expected losses. The Company recognizes in net income the amount needed to adjust the ACL for management’s current estimate of expected losses. The Company generally uses an eight-quarter forecast period, based on a single forecast scenario or a blend of multiple forecast scenarios, using variables management believes are most relevant to each portfolio segment. For periods beyond which management is able to develop reasonable and supportable forecasts, the Company reverts to the average historical loss rate, reflecting historical default probabilities and loss severities, using a reversion speed that approximates four quarters. The forecast period and scenarios used are reviewed on a quarterly basis and may be adjusted based on management's view of the current economic conditions and level of predictability the forecast can provide. While quantitative allowance methodologies strive to reflect all risk factors, any estimate involves assumptions and uncertainties resulting in some level of imprecision. Imprecision exists in the estimation process due to the inherent time lag between obtaining information, performing the calculation, as well as variations between estimates and actual outcomes. As a result, amounts determined under the methodologies described above are adjusted by management to consider the potential impact of other qualitative factors not captured in the quantitative model adjustments which include, but are not limited to, the following: imprecision or conditions not captured in economic scenario assumptions, emerging risks related to either changes in the internal or external environment that are affecting specific portfolios, trends in loan or portfolio level credit metrics not captured in quantitative modeling, or model imprecision adjustments. The consideration of these items results in adjustments to allowance amounts included in the Company’s allowance for credit losses for each loan portfolio. The Company’s ACL is calculated using collectively evaluated and individually evaluated loans. Even though portions of the allowance may be allocated to specific loans or pools of loans, the entire allowance is available for any credit that, in management’s judgment, should be charged off. When a loan no longer shares similar risk characteristics with its segment, the asset is assessed to determine whether it should be included in another pool or should be individually evaluated. The Company’s threshold for individually evaluated loans includes all non-accrual loans with a net book balance in excess of $1.0 million. During an acquisition, the Company may identify accruing loans that do not share similar risk characteristics as pooled loans and therefore be individually evaluated. These loans are identified during the credit review process, have unique characteristics or circumstances, and identified as purchased credit-deteriorated (“PCD”) loans, though the loans may remain on accrual status. Management will monitor the credit environment and make adjustments to this threshold in the future if warranted. Based on the threshold above, consumer financial assets will generally remain in pools unless they meet the dollar threshold. The expected credit losses on individually evaluated loans will be estimated based on discounted cash flow analysis unless the loan meets the criteria for use of the fair value of collateral, either by virtue of an expected foreclosure or through meeting the definition of collateral-dependent. Accruing individually evaluated loans will remain in this status until 1) the loan is upgraded to pass, or 2) the loan is downgraded to non-accrual and follow the non-accrual individually evaluated process. Financial assets that have been individually evaluated can be returned to a pool for purposes of estimating the expected credit loss insofar as their credit profile improves and that the repayment terms were not considered to be unique to the asset. Management measures expected credit losses over the contractual term of a loan. When determining the contractual term, the Company considers expected prepayments but is precluded from considering expected extensions, renewals, or modifications. Loans modified to a borrower experiencing financial difficulty are reviewed by the Bank to determine if an interest rate reduction, a term extension, an other-than-insignificant payment delay, a principal forgiveness, or any combination of these has occurred. The ACL includes expected losses from modifications of receivables to borrowers experiencing financial difficulty. Losses on modifications of non-accrual loans over $1 million to borrowers experiencing financial difficulty are estimated on an individual basis. Because the effect of the remainder of modifications made to borrowers experiencing financial difficulty is already incorporated into the measurement methodologies used to estimate the allowance, they are accounted for as pooled loans. PCD assets are defined as acquired individual financial assets (or acquired groups of financial assets with similar risk characteristics) 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. The Company records acquired PCD loans by adding the expected credit losses (i.e., allowance for credit losses) to the purchase price of the financial assets rather than recording through the provision for credit losses in the income statement. The expected credit loss, as of the acquisition day, of a PCD loan is added to the allowance for credit losses. The non-credit discount or premium is the difference between the unpaid principal balance and the amortized cost basis as of the acquisition date. Subsequent to the acquisition date, the change in the ACL on PCD loans is recognized through the Provision for Credit Losses in the Consolidated Statements of Income. The non-credit discount or premium is accreted or amortized, respectively, into interest income over the remaining life of the PCD loan on a level-yield basis. The Company follows its nonaccrual policy by reversing contractual interest income in the income statement when the Company places a loan on nonaccrual status. Therefore, management excludes the accrued interest receivable balance from the amortized cost basis in measuring expected credit losses on the portfolio and does not record an allowance for credit losses on accrued interest receivable. As of March 31, 2026 and December 31, 2025, the accrued interest receivables for loans recorded in Other Assets were $189.2 million and $186.5 million, respectively. The Company has a variety of assets that have a component that qualifies as an off-balance sheet exposure. These primarily include undrawn portions of revolving lines of credit and standby letters of credit. The expected losses associated with these exposures within the unfunded portion of the expected credit loss are recorded as a liability on the balance sheet. Management has determined that a majority of the Company’s off-balance sheet credit exposures are not unconditionally cancellable. Management completes funding studies based on internal historical data to estimate the percentage of unfunded loan commitments that will ultimately be funded to calculate the reserve for unfunded commitments. Management applies this funding rate, along with the loss factor rate determined for each pooled loan segment, to unfunded loan commitments, excluding unconditionally cancellable exposures and letters of credit, to arrive at the reserve for unfunded loan commitments. As of March 31, 2026 and December 31, 2025, the liabilities recorded for expected credit losses on unfunded commitments were $69.2 million and $69.6 million, respectively. The current adjustment to the reserve for unfunded commitments is recognized through the Provision for Credit Losses in the Consolidated Statements of Income. The methodology used in the estimation of the allowance, which is performed at least quarterly, is designed to be dynamic and responsive to changes in portfolio credit quality and forecasted economic conditions. Changes are reflected in the pool-basis allowance and in reserves assigned on an individual basis as the collectability of classified loans is evaluated with new information. As the Company’s portfolio has matured, historical loss ratios have been closely monitored. The review of the appropriateness of the allowance is performed by executive management and presented to the Audit and Risk Committees of the Board of Directors for their review. The committees report to the board as part of the board's quarterly review of the Company’s consolidated financial statements.
Reclassification and Correction	Reclassification and Correction Certain amounts previously reported have been reclassified to conform to the current quarter’s presentation. Such reclassifications had no effect on net income and shareholders’ equity.

Disclosure of accounting policy for credit loss on financial instrument measured at amortized cost basis, net investment in lease, off-balance sheet credit exposure, and available-for-sale debt security. Includes, but is not limited to, methodology used to estimate allowance for credit loss, how writeoff of uncollectible amount is recognized, and determination of past due status and nonaccrual status.

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SouthState Bank Corp 10-Q