Accounting Policies Recently Adopted

Trustmark has consistently applied its accounting policies to all periods presented in the accompanying consolidated financial statements.

Pending Accounting Pronouncements

ASU 2024-03, “Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses.” Issued in November 2024, ASU 2024-03 with the objective of providing investors with more decision-useful information regarding a public business entity's expenses by enhancing disclosures on income statement expenses. Investor feedback indicated a strong preference for the disclosure of disaggregated financial reporting information as a top priority for the FASB. Detailed knowledge of an entity's expenses is crucial for understanding its prospects for future cash flows and for making performance comparisons over time and with other entities. Investors emphasized that information regarding cost of sales, selling, general, and administrative expenses, employee compensation costs, depreciation and amortization, and research and development expenditure would enhance their comprehension of an entity's cost structure and ability to forecast future cash flows. The ASU applies exclusively to public business entities and mandates additional disclosures about specific expense categories on both annual and interim bases in the notes to financial statements that are not currently required. The amendments do not alter or eliminate existing expense disclosure requirements nor change requirements for presenting expenses on the face of the income statement. However, they do specify that certain existing disclosures must now appear in the same tabular format as the new disaggregation requirements. The FASB issued ASU 2025-01 in January 2025, clarifying that the amendments in ASU 2024-03 are effective for public business entities for annual reporting periods beginning after December 15, 2026, and for interim reporting periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted. Trustmark intends to adopt the amendments of ASU 2024-03 effective

January 1, 2027, and will include the required annual disclosures in its Annual Report on Form 10-K for the year ending December 31, 2027, and required interim disclosures in its Quarterly Report on Form 10-Q for the period ending March 31, 2028. Trustmark is currently evaluating the changes to disclosures required by ASU 2024-03; however, adoption of ASU 2024-03 is not expected to have a material impact to Trustmark’s consolidated financial statements or results of operations.

ASU 2025-06, “Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software.” Issued in September 2025, ASU 2025-06 seeks to update the guidance on accounting for software due to changes in how software is generally developed. When software accounting guidance was first issued, companies developing software generally followed a prescriptive and sequential development method (e.g., waterfall). Since then, many companies have adopted a more incremental and iterative development method (i.e., agile). As a result, many stakeholders noted the challenges of applying current internal-use software accounting requirements that do not specifically address software developed using an incremental and iterative method, which has led to diversity in practice in determining when to begin capitalizing software costs. The amendments of ASU 2025-06 remove all references to a prescriptive and sequential software development method (referred to as "project stages") throughout FASB ASC Subtopic 350-40, and require an entity to start capitalizing software costs when both of the following occur: (1) Management has authorized and committed to funding the software project; and (2) it is probable that the project will be completed and the software will be used to perform the function intended (referred to as the "probable-to-complete recognition threshold"). In evaluating the probable-to-complete recognition threshold, a company is required to consider whether there is significant uncertainty associated with the development activities of the software. ASU 2025-06 is effective for all entities for annual reporting periods beginning after December 15, 2027, and for interim reporting periods within those annual reporting periods. Early adoption is permitted as of the beginning of an annual reporting period. Trustmark intends to adopt the amendments of ASU 2025-06 effective January 1, 2028. Trustmark is currently evaluating the impact the amendments of ASU 2025-06 will have in regards to its internal-use software; however, adoption of ASU 2025-06 is not expected to have a material impact to Trustmark’s consolidated financial statements or results of operations.

ASU 2025-08, “Financial Instruments—Credit Losses (Topic 326): Purchased Loans.” Issued in November 2025, ASU 2025-08 expands the gross-up approach for accounting for credit losses on acquired financial assets, addressing complexity and comparability issues caused by previous distinctions between purchased financial assets with credit deterioration (PCD assets) and non-PCD assets. ASU 2025-08 requires loans (excluding credit cards) acquired without significant credit deterioration and deemed "seasoned" to be accounted for using the gross-up approach. For these purchased seasoned loans (loans, excluding credit cards, debt securities and trade receivables, acquired through a business combination accounted for using the acquisition method or other loans acquired through transfers not accounted for as business combinations purchased at least 90 days after origination and not originated by the acquirer), the initial ACL is added to the purchase price to determine the amortized cost basis. Entities can elect to measure this ACL using the amortized cost basis if not employing a discounted cash flow method, with elections being irrevocable. ASU 2025-08 clarifies that purchased seasoned loans are subject to the same accrual policies as originated assets and are not subject to the guidance that permits interest income accrual on PCD assets when there is a reasonable expectation for amounts to be collected or recovery limitations. ASU 2025-08 also amends disclosure requirements for the rollforward of the ACL to present the initial allowance recognized on such loans separately. ASU 2025-08 is effective for annual periods after December 15, 2026, and for interim reporting periods within those annual reporting periods, with early adoption allowed and prospective application required. Trustmark intends to adopt the amendments of ASU 2025-08 on January 1, 2027; however, as the amendments of this ASU must be applied on a prospective basis, adoption of this ASU will have no impact to Trustmark's consolidated financial statements or results of operations until an acquisition occurs.

ASU 2025-09, “Derivatives and Hedging (Topic 815): Hedge Accounting Improvements.” Issued in November 2025, ASU 2025-09 updates hedge accounting guidance to address global reference rate reform and better align hedge accounting with entities' risk management practices. Key changes include broadening eligible hedged risks for cash flow hedges via a "similar risk exposure" test, introducing an optional operable model for hedge accounting on choose-your-rate debt instruments, permitting hedge accounting for forecasted spot and forward transactions in nonfinancial assets if price components are clearly related and removing the net written option test for certain derivatives. The amendments of ASU 2025-09 also resolve recognition mismatches in dual hedge strategies involving foreign-currency-denominated debt. The amendments of ASU 2025-09 are effective for annual reporting periods beginning after December 15, 2026, and for interim reporting periods within those annual reporting periods, and should be applied on a prospective basis for all hedging relationships. Early adoption is permitted. Entities may also modify certain critical terms of existing hedging relationships without de-designating the hedge upon adoption. Trustmark intends to adopt the amendments of ASU 2025-09 effective January 1, 2027. Trustmark is currently evaluating the impact the amendments of ASU 2025-09 will have in regard to its derivative and hedging instruments; however, adoption of ASU 2025-09 is not expected to have a material impact to Trustmark’s consolidated financial statements or results of operations.