Trustmark Corporation

ITEM 1A. RISK FACTORS

Trustmark and its subsidiaries could be adversely impacted by various risks and uncertainties, which are difficult to predict. As a financial institution, Trustmark has significant exposure to market risks, including interest rate risk, liquidity risk and credit risk. This

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section includes a description of the risks, uncertainties and assumptions identified by Management that could, individually or in combination, materially affect Trustmarks financial condition and results of operations, as well as the value of Trustmarks financial instruments in general, and Trustmark common stock, in particular. Additional risks and uncertainties that Management currently deems immaterial or is unaware of may also impair Trustmarks financial condition and results of operations. This report is qualified in its entirety by the risk factors that are identified below.

Risks Related to Trustmarks Business

Interest Rate Risks

Trustmarks largest source of revenue (net interest income) is subject to interest rate risk.

Trustmarks profitability depends to a large extent on net interest income, which is the difference between income on interest-earning assets, such as loans and investment securities, and expense on interest-bearing liabilities, such as deposits and borrowings. Trustmark is exposed to interest rate risk in its core banking activities of lending and deposit taking, since assets and liabilities reprice at different times and by different amounts as interest rates change. Trustmark is unable to predict changes in market interest rates, which are affected by many factors beyond Trustmarks control, including inflation, recession, unemployment, money supply, domestic and international events and changes in the United States and other financial markets. Market interest rates began to riseremained elevated during most of 2022 after an extended period at historical lows. Starting in March4. The FRB maintained the target federal funds rate at a range of 5.25% to 5.50% from July 2023 through September 2024. In September 20224, the FRB began raisilowering the target federal funds rate for the first time in three years and continued withmaking multiple indecreases throughout 2022 andduring the fourth quarter of 2023, up4 to a range of 54.25% to 54.50% as of December 2023. In addition,4, based on its confidence that inflation was moving substantially toward 2.00% and that the risks to achieving the FRB increased t's employment and inflation goals were roughly balanced. In addition, the FRB mainterestained thate rate it paysid on reserves multiple times duringat 5.40% from July 2023 through September 2022 and4. In September 2023 from 0.10% to 54, the FRB made the first of multiple declines in the rate it pays on reserves, lowering the rate to 4.40% as of December 2023. As interest4. Prior period rates have increases increased, so hav the competitive pressures on the deposit cost of funds. This has been exacerbWhile rated by the bank failures in the first half of 2023 and the cuts potentially resulting heightenedduce those competition for deposits, which has also affected theve pressures, they increase pressure on Trustmark's net interest that Trustt mark pays on deposigin, a key component to its financial results. It is not possible to predict the pace and magnitude of changes in interest rates, or the impact rate changes will have on Trustmark's results of operations.

Financial simulation models are the primary tools used by Trustmark to measure interest rate exposure. Using a wide range of scenarios, Management is provided with extensive information on the potential impact to net interest income caused by changes in interest rates. Models are structured to simulate cash flows and accrual characteristics of Trustmarks balance sheet. Assumptions are made about the direction and volatility of interest rates, the slope of the yield curve and the changing composition of Trustmarks balance sheet, resulting

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from both strategic plans and customer behavior. In addition, the model incorporates Managements assumptions and expectations regarding such factors as loan and deposit growth, pricing, prepayment speeds and spreads between interest rates. Trustmarks simulation model using static balances at December 31, 20234, estimated that in the event of a hypothetical 200 basis point increase in interest rates, net interest income may increase 0.58%, while a hypothetical 100 basis point increase in interest rates, may increase net interest income 0.34%. In the event of a hypothetical 100 basis point decrease in interest rates using static balances at December 31, 20234, it is estimated net interest income may decrease by 0.41.2%, while a hypothetical 200 basis point decrease in interest rates, may decrease net interest income 13.0%.

Net interest income is Trustmarks largest revenue source, and it is important to discuss how Trustmarks interest rate risk may be influenced by the various factors shown below:

In general, for a given change in interest rates, the amount of the change in value (positive or negative) is larger for assets and liabilities with longer remaining maturities. The shape of the yield curve may affect new loan yields, funding costs and investment income differently.

The remaining maturity of various assets or liabilities may shorten or lengthen as payment behavior changes in response to changes in interest rates. For example, if interest rates decline sharply, fixed-rate loans may pre-pay, or pay down, faster than anticipated, thus reducing future cash flows and interest income. Conversely, if interest rates increase, depositors may cash in their certificates of deposit prior to term (notwithstanding any applicable early withdrawal penalties) or otherwise reduce their deposits to pursue higher yielding investment alternatives. Repricing frequencies and maturity profiles for assets and liabilities may occur at different times. For example, in a falling rate environment, if assets reprice faster than liabilities, there will be an initial decline in earnings. Moreover, if assets and liabilities reprice at the same time, they may not be by the same increment. For instance, if the federal funds rate increased 50 basis points, rates on demand deposits may rise by 10 basis points, whereas rates on prime-based loans will instantly rise 50 basis points.

Financial instruments do not respond in a parallel fashion to rising or falling interest rates. This causes asymmetry in the magnitude of changes in net interest income, net economic value and investment income resulting from the hypothetical increases and decreases in interest rates. Therefore, Management monitors interest rate risk and adjusts Trustmarks investment, funding and hedging strategies to mitigate adverse effects of interest rate shifts on Trustmarks balance sheet.

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Trustmark utilizes derivative contracts to hedge the mortgage servicing rights (MSR) in order to offset changes in fair value resulting from changes in interest rate environments. In spite of Trustmarks due diligence in regard to these hedging strategies, significant risks are involved that, if realized, may prove such strategies to be ineffective, which could adversely affect Trustmarks financial condition or results of operations. Risks associated with these strategies include the risk that counterparties in any such derivative and other hedging transactions may not perform; the risk that these hedging strategies rely on Managements assumptions and projections regarding these assets and general market factors, including prepayment risk, basis risk, market volatility and changes in the shape of the yield curve, and that these assumptions and projections may prove to be incorrect; the risk that these hedging strategies do not adequately mitigate the impact of changes in interest rates, prepayment speeds or other forecasted inputs to the hedging model; and the risk that the models used to forecast the effectiveness of hedging instruments may project expectations that differ from actual results. In addition, increased regulation of the derivative markets may increase the cost to Trustmark to implement and maintain an effective hedging strategy.

Trustmark closely monitors the sensitivity of net interest income and investment income to changes in interest rates and attempts to limit the variability of net interest income as interest rates change. Trustmark makes use of both on- and off-balance sheet financial instruments to mitigate exposure to interest rate risk.

Trustmark may be adversely affected by the transition from the London Interbank Offered Rate (LIBOR) as a reference rate.

In 2017, the United Kingdoms Financial Conduct Authority (FCA), which regulates LIBOR, announced that after the end of 2021 it would no longer compel banks to submit the rates required to calculate LIBOR. On March 5, 2021, the FCA confirmed that the publication of most LIBOR term rates would end on June 30, 2023 (excluding one-week U.S. LIBOR and two-month U.S. LIBOR, the publication of which ended on December 31, 2021). The Alternative Reference Rates Committee (ARRC), a committee of U.S. financial market participants, identified the Secured Overnight Financing Rate (SOFR) as the reference rate that represents best practice as the alternative to LIBOR for use in derivatives and other financial contracts that are currently indexed to USD-LIBOR. However, there are conceptual and technical differences between LIBOR and SOFR. The federal banking agencies encouraged banking organizations to cease entering into new contracts that use US$ LIBOR as a reference rate by no later than December 31, 2021, and to ensure existing contracts have robust fallback language that includes a clearly defined alternative reference rate.

On December 16, 2022, the FRB adopted a final rule that implemented the Adjustable Interest Rate (LIBOR) Act by identifying benchmark rates based on SOFR that will replace LIBOR in certain financial contracts after June 30, 2023. Following the LIBOR

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cessation date of June 30, 2023, the nationwide process for replacing LIBOR in financial contracts that mature thereafter and that do not provide for an effective means to replace LIBOR upon its cessation took effect pursuant to the Adjustable Interest Rate (LIBOR) Act. For contracts in which a party has the discretion to identify a replacement rate, the Adjustable Interest Rate (LIBOR) Act also provides a safe harbor to parties if they choose the SOFR-based benchmark replacement rate to be identified by the FRB. Trustmark transitioned to SOFR for new variable rate loans, derivative contracts, borrowings and other financial instruments as of January 1, 2022.

Trustmark had a significant number of loans, derivative contracts, borrowings and other financial instruments with attributes that were either directly or indirectly dependent on LIBOR. As of December 31, 20234, all of Trustmarks LIBOR exposure was remediated or in the process of being remediated. The transition from LIBOR has resulted in and could continue to result in added costs and employee efforts and could present additional risk. Since alternative reference rates are calculated differently than LIBOR, payments under contracts referencing new alternative reference rates will differ from those referencing LIBOR. Trustmark cannot predict what the ultimate impact of the transition from LIBOR will be; however, Trustmark has implemented various measures to manage the transition and mitigate risks.

Credit and Lending Risks

Trustmark is subject to lending risk, which could impact the adequacy of the allowance for credit losses and results of operations.

There are inherent risks associated with Trustmarks lending activities. If trends in the housing and real estate markets were to revert to or decline below recession levels, Trustmark may experience higher than normal delinquencies and credit losses. Moreover, if the United States economy returns to a recessionary state, Management expects that it could severely affect economic conditions in Trustmarks market areas and that Trustmark could experience significantly higher delinquencies and credit losses. In addition, bank regulatory agencies periodically review Trustmarks allowance for credit losses and may require an increase in the provision for credit losses or the recognition of further charge-offs, based on judgments different from those of Management. As a result, Trustmark may elect, or be required, to make further increases in its provision for credit losses in the future, particularly if economic conditions deteriorate.

Additionally, Trustmark may rely on information furnished by or on behalf of customers and counterparties in deciding whether to extend credit or enter into other transactions. This information could include financial statements, credit reports, business plans, and

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other information. Trustmark may also rely on representations of those customers, counterparties or other third parties, such as independent auditors, as to the accuracy and completeness of that information. Reliance on inaccurate or misleading financial statements, credit reports or other information could have a material adverse impact on Trustmarks business, financial condition and results of operations.

Trustmark is subject to environmental liability risk associated with lending activities.

A significant portion of Trustmarks loan portfolio is secured by real property. During the ordinary course of business, Trustmark forecloses on and takes title to properties securing certain loans. In doing so, there is a risk that hazardous or toxic substances could be found on these properties. If hazardous or toxic substances are found, Trustmark may be liable for remediation costs, as well as for personal injury and property damage, civil fines and criminal penalties regardless of when the hazardous conditions or toxic substances first affected any particular property. Environmental laws may require Trustmark to incur substantial expenses and may materially reduce the affected propertys value or limit Trustmarks ability to use or ability to sell the affected property or to repay the indebtedness secured by the property. In addition, future laws or more stringent interpretations or enforcement policies with respect to existing laws may increase Trustmarks exposure to environmental liability. Environmental reviews of nonresidential real estate before initiating foreclosure actions may not be sufficient to detect all potential environmental hazards. The remediation costs and any other financial liabilities associated with an environmental hazard could have a material adverse effect on Trustmarks business, financial condition and results of operations.

Declines in asset values may result in credit losses and adversely affect the value of Trustmarks investments.

Trustmark maintains an investment portfolio that includes, among other asset classes, obligations of states and municipalities, agency debt securities and agency mortgage-related securities. The market value of investments in Trustmarks investment portfolio may be affected by factors other than interest rates or the underlying performance of the issuer of the securities, such as ratings downgrades, adverse changes in the business climate and a lack of pricing information or liquidity in the secondary market for certain investment securities. In addition, government involvement or intervention in the financial markets or the lack thereof or market perceptions regarding the existence or absence of such activities could affect the market and the market prices for these securities.

On a quarterly basis, Trustmark evaluates investments and other assets for expected credit losses. At December 31, 20234, gross unrealized losses on securities for which an allowance for credit losses has not been recorded totaled $196.130.0 million. Trustmark may be required to record credit loss expense if these investments suffer a decline in value that is the result of a credit loss. If Trustmark

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determines that a credit loss exists, the credit portion of the allowance would be measured using a discounted cash flow (DCF) analysis using the effective interest rate as of the securitys purchase date. The amount of credit loss Trustmark may record is limited to the amount by which the amortized cost exceeds the fair value, which could have a material adverse effect on results of operations in the period in which a credit loss, if any, occurs.

Liquidity Risk

Trustmark is subject to liquidity risk, which could disrupt its ability to meet its financial obligations.

Liquidity refers to Trustmarks ability to ensure that sufficient cash flow and liquid assets are available to satisfy current and future financial obligations, including demand for loans and deposit withdrawals, funding operating costs and other corporate purposes. Liquidity risk arises whenever the maturities of financial instruments included in assets and liabilities differ or when assets cannot be liquidated at fair market value as needed. Trustmark obtains funding through deposits and various short-term and long-term wholesale borrowings, including federal funds purchased and securities sold under repurchase agreements, the Federal Reserve Discount Window (Discount Window) and Federal Home Loan Bank (FHLB) advances. Any significant restriction or disruption of Trustmarks ability to obtain funding from these or other sources could have a negative effect on Trustmarks ability to satisfy its current and future financial obligations, which could materially affect Trustmarks financial condition or results of operations.

In addition to the risk that one or more of the funding sources may become constrained due to market conditions unrelated to Trustmark, there is the risk that Trustmarks credit profile may decline such that one or more of these funding sources becomes partially or wholly unavailable to Trustmark.

Trustmark attempts to quantify such credit event risk by modeling bank specific and systemic scenarios that estimate the liquidity impact. Trustmark estimates such impact by attempting to measure the effect on available unsecured lines of credit, available capacity from secured borrowing sources and securitizable assets. To mitigate such risk, Trustmark maintains available lines of credit with the Federal Reserve Bank of Atlanta (FRBA) and the FHLB of Dallas that are secured by loans and investment securities. Management continuously monitors Trustmarks liquidity position for compliance with internal policies.

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External and Market-Related Risks

Trustmarks business may be adversely affected by conditions in the financial markets and economic conditions in general.

Economic activity improved slightmoderately during 20234; however, economic concerns remain as a result of the cumulative weight of uncertainty regarding the potential economic impact of geopolitical developments, such as the conflicts in Ukraine and the Middle East, inflation, the consequences of bank failures and oother economic and industry volatility, the 2024 political cycle in thecurrent United States, supply chain issu presidential administration's policies, higher energy prices and broader price pressures. Doubts surrounding the near-term direction of global markets, and the potential impact of these trends on the United States economy, are expected to persist for the near term. While Trustmarks customer base is wholly domestic, international economic conditions affect domestic conditions, and thus may have an impact upon Trustmarks financial condition or results of operations. Strategic risk, including threats to business models from riincreasing rates anpressures on net interest margins and modest economic growth, remains high. Managements ability to plan, prioritize and allocate resources in this environment will be critical to Trustmarks ability to sustain earnings that will attract capital. Because of the complexities presented by current economic conditions, Management will continue to be challenged in identifying alternative sources of revenue, prudently diversifying assets, liabilities and revenue and effectively managing the costs of compliance.

Market interest rates began to rise during 2022 after an extended periodremained elevated until September 2024, at historical lows and continued to rise in 2023. As interestwhich time interest rates began to decline. Prior period rates have increases increased, so hav the competitive pressures on the deposit cost of funds. This has been exacerbWhile rated by bank failures and cuts potentially reduce the resulting heightenedose competition for deposits, which has also affected theve pressures, they increase pressure on Trustmark's net interest that Trustmark pays on deposigin, a key component to its financial results. It is not possible to predict the pace and magnitude of changes to interest rates, or the impact rate changes will have on Trustmarks results of operations.

Trustmark does not assume that current uncertain conditions in the economy will improve significantly in the near future. A weakened economy could affect Trustmark in a variety of substantial and unpredictable ways. In particular, Trustmark may face the following risks in connection with these events:

Market developments and the resulting economic pressure on consumers may affect consumer confidence levels and may cause increases in delinquencies and default rates, which, among other effects, could further affect Trustmarks charge-offs and provision for credit losses.

Loan performance could experience a significantly extended deterioration or loan default levels could accelerate, foreclosure activity could significantly increase, or Trustmarks assets (including loans and investment securities) could materially decline in value, any one of which, or any combination of more than one of which, could have a material adverse effect on Trustmarks financial condition or results of operations.

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Managements ability to measure the fair value of Trustmarks assets could be adversely affected by market disruptions that could make valuation of assets more difficult and subjective. If Management determines that a significant portion of its assets have values that are significantly below their recorded carrying value, Trustmark could recognize a material charge to earnings in the quarter during which such determination was made, Trustmarks capital ratios would be adversely affected by any such charge, and a rating agency might downgrade Trustmarks credit rating or put Trustmark on credit watch.

The rising interest rate environment during 2022 and 2023, the resulting industry-wide reduction in the fair value of securities portfolios and the bank runs that led to the failures of some financial institutions in March 2023, among other events, have resulted in a current state of volatility and uncertainty with respect to the health of the United States banking system. There is heightened awareness around liquidity, uninsured deposits, deposit composition, unrecognized investment losses and capital. It is difficult to predict the extent to which these challenging economic conditions will persist or whether recent progress in the economic recovery will instead shift to the potential for further decline. If the economy does weaken in the future, it is uncertain how Trustmarks business would be affected and whether Trustmark would be able to successfully mitigate any such effects on its business. Accordingly, these factors in the United States (and, indirectly, global) economy could have a material adverse effect on Trustmarks financial condition and results of operations.

Trustmark operates in a highly competitive financial services industry.

Trustmark faces substantial competition in all areas of its operations from a variety of different competitors, many of which are larger and may have greater financial resources. Such competitors primarily include banks, as well as community banks operating nationwide and regionally within the various markets in which Trustmark operates. Trustmark also faces competition from many other types of financial institutions, including savings and loans, credit unions, finance companies, brokerage firms, insurance companies, factoring companies and other financial intermediaries. Additionally, fintech developments, such as blockchain and other distributed ledger technologies, have the potential to disrupt the financial industry and change the way banks do business. The financial services industry could become even more competitive as a result of legislative, regulatory and technological changes and continued consolidation.

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Some of Trustmarks competitors have fewer regulatory constraints and may have lower cost structures. Additionally, due to their size, many of Trustmarks larger competitors may be able to achieve economies of scale and, as a result, may offer a broader range of products and services as well as better pricing for those products and services than Trustmark.

Trustmarks ability to compete successfully depends on a number of factors, including: the ability to develop, maintain and build upon long-term customer relationships based on top quality service, high ethical standards and safe, sound assets; the ability to continue to expand Trustmarks market position through organic growth and acquisitions; the scope, relevance and pricing of products and services offered to meet customer needs and demands; the rate at which Trustmark introduces new products and services relative to its competitors; and industry and general economic trends. Failure to perform in any of these areas could significantly weaken Trustmarks competitive position, which could adversely affect Trustmarks financial condition or results of operations.

The soundness of other financial institutions could adversely affect Trustmark.

Financial services institutions are interrelated as a result of trading, clearing, counterparty or other relationships. As a result, defaults by, or questions or rumors about, one or more financial services institutions or the financial services industry in general, could lead to market-wide liquidity problems, which could, in turn, lead to defaults or losses by Trustmark and by other institutions. Trustmark has exposure to many different industries and counterparties, and routinely executes transactions with counterparties in the financial services industry, including commercial banks, brokers and dealers, investment banks, mutual funds, and other institutional clients. Many of these transactions expose Trustmark to credit risk in the event of default of its counterparty or client. In addition, Trustmarks credit risk may be exacerbated when the collateral it holds cannot be realized upon or is liquidated at prices not sufficient to recover the full amount of the credit or derivative exposure owed to Trustmark. Losses related to these credit risks could materially and adversely affect Trustmarks results of operations.

Compliance and Regulatory Risks

Trustmark is subject to extensive government regulation and supervision and possible enforcement and other legal actions.

Trustmark, primarily through TNB and certain nonbank subsidiaries, is subject to extensive federal and state regulation and supervision, which vests a significant amount of discretion in the various regulatory authorities. Banking regulations are primarily intended to protect depositors funds, federal deposit insurance funds and the banking system as a whole, not security holders. These regulations and supervisory guidance affect Trustmarks lending practices, capital structure, investment practices, dividend policy and growth, among other things. Congress and federal regulatory agencies continually review banking laws, regulations and policies for possible changes. Changes to statutes, regulations or regulatory policies or supervisory guidance, including changes in interpretation or implementation or statutes, regulations, policies and supervisory guidance, could affect Trustmark in substantial and unpredictable ways. Such changes

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could subject Trustmark to additional costs, limit the types of financial services and products Trustmark may offer and/or increase the ability of nonbanks to offer competing financial services and products, among other things. Failure to comply with laws, regulations, policies or supervisory guidance could result in enforcement and other legal actions by Federal or state authorities, including criminal and civil penalties, the loss of FDIC insurance, the revocation of a banking charter, civil money penalties, other sanctions by regulatory agencies and/or reputational damage. In this regard, government authorities, including bank regulatory agencies, continue to pursue enforcement agendas with respect to compliance and other legal matters involving financial activities, which heightens the risks associated with actual and perceived compliance failures. Any of the foregoing could have a material adverse effect on Trustmarks financial condition or results of operations.

Trustmark is subject to numerous laws designed to protect consumers, including fair lending laws, and failure to comply with these laws could lead to a wide variety of sanctions.

The Equal Credit Opportunity Act, the Fair Housing Act and other fair lending laws and regulations impose nondiscriminatory lending requirements on financial institutions. The Department of JusticeOJ and other federal agencies are responsible for enforcing these laws and regulations. A successful regulatory challenge to an institutions performance under fair lending laws and regulations could result in a wide variety of direct or indirect negative consequences, including damages and civil money penalties, injunctive relief, restrictions on mergers and acquisitions activity, restrictions on geographic expansion and restrictions on entering new business lines. Private parties may also have the ability to challenge an institutions performance under fair lending laws in private class action litigation. Such actions could have a material adverse effect on Trustmarks business, financial condition or results of operations. In 2021, TNB settled a fair lending enforcement action with the Department of JusticeOJ, the OCC and the CFPB and incurred a one-time settlement expense of $5.0 million and made other commitments to enhance credit opportunities to residents of majority-Black and Hispanic neighborhoods in the Memphis metropolitan statistical area. Trustmark and TNB could be subject to other enforcement actions in the future.

In addition, financial institutions face scrutiny on actions and policies that are deemed to adversely impact consumers under the Dodd-Frank Acts prohibition against unfair, deceptive or abusive acts and practices and Section 5 of the Federal Trade Commission Acts

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prohibition against unfair or deceptive acts and practices. Bank regulators and the CFPB are responsible for enforcing these prohibitions against banking organizations. These prohibitions have been applied to prohibit perceived customer abuse in connection with a range of products, services, and practices, including account openings and fees charged where inadequate or no services are rendered for which charges were imposed, as well as other instances where consumers may have been misled through bank disclosures. In addition, the enforcement priorities of the agencies enforcing consumer protection laws have evolved over time and may continue to do so.

TNB's CRA rFailure by Trustmark to perform sating of "Needs to Improve"sfactorily on its CRA evaluations could make it more difficult for Trustmarks business to grow.

The performance of a bank under the CRA in meeting the credit needs of its community is a factor that must be taken into consideration when the federal banking agencies evaluate applications related to mergers and acquisitions, as well as branch opening and relocations. As of its last examination, TNB received a CRA rating of Needs to ImproveOutstanding, which is downgradedrepresented an improvement from its prior rating of Satisfactory. Theevious CRA rating of Needs to Improve adversely affects. TNBs abilityfailure to obmaintain regulatat least a Satisfactory approvals to engageCRA rating in certain expansionarthe future could adversely activities, including certain mergers andffect its ability to complete the acquisitions of and othe establishment of bank branches. These limitar financial institutions will remain in place until or open a new branch. If TNB receives a n overall CRA rating of at leastss than Satisfactory following a subsequent CRA examination. The precise timin the future, the OCC would not re-evaluate its rating of the completion of that until TNBs next CRA examination and any results therefrom will not be known until later, which may not occur for several more years, and it is possible that TNBs currenta low CRA rating would not improve in the next examinationfuture.

Trustmark is subject to stringent capital requirements.

Under the regulatory capital rules of the FRB, OCC, and FDIC that implement a set of capital requirements issued by the Basel Committee on Banking Supervision known as Basel III, Trustmark and TNB are required to maintain a common equity Tier 1 capital to risk-weighted assets ratio of at least 7.0% (a minimum of 4.5% plus a capital conservation buffer of 2.5%), a Tier 1 capital to risk-weighted assets ratio of at least 8.5% (a minimum of 6.0% plus a capital conservation buffer of 2.5%), a total capital to risk-weighted assets ratio of at least 10.5% (a minimum of 8.0% plus a capital conservation buffer of 2.5%) and a leverage ratio of Tier 1 capital to total consolidated assets of at least 4.0%. In addition, for TNB to be well-capitalized under the banking agencies prompt corrective action framework, it must have a common equity Tier 1 capital ratio of at least 6.5%, a Tier 1 capital ratio of at least 8.0%, a total capital ratio of at least 10.0% and a leverage ratio of at least 5.0%, and must not be subject to any written agreement, order or capital directive, or prompt corrective action directive issued by its primary federal regulator to meet and maintain a specific capital level for any capital measure.

The capital rules also include stringent criteria for capital instruments to qualify as Tier 1 or Tier 2 capital. For instance, the rules effectively disallow newly issued trust preferred securities to be a component of a holding companys Tier 1 capital. Trustmark will continue to count $60.0 million in outstanding trust preferred securities issued by the Trust as Tier 1 capital up to the regulatory limit, as permitted by a grandfather provision in the capital rules, but this grandfather provision may cease to apply if Trustmark consummates an acquisition of a depository institution holding company and the resulting organization has $15 billion of more in total assets.

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Financial Accounting Standards Board (FASB) Accounting Standard Codification (ASC) Topic 326, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments, requires Trustmark to recognize all expected credit losses over the life of a loan based on historical experience, current conditions and reasonable and supportable forecasts. FASB ASC Topic 326 generally is expected to results in earlier recognition of credit losses, which would increase reserves and decrease capital. Additionally, the allowance for credit losses model could be materially impacted by changes in current and forecasted macroeconomic conditions. It is not possible to predict the timing or magnitude of changes in macroeconomic conditions or the impact such changes could have on Trustmarks allowance for credit losses; however, material changes in the allowance for credit losses could have a material impact on Trustmarks reserves and capital.

The regulatory capital rules applicable to Trustmark and TNB may continue to evolve as a result of new requirements established by the Basel Committee on Banking Supervision or legislative, regulatory or accounting changes in the United States. Management cannot predict the effect that any changes to current capital requirements would have on Trustmark and TNB.

Trustmarks use of third-party service providers and Trustmarks other ongoing third-party business relationships are subject to increasing regulatory requirements and attention.

Trustmark regularly uses third-party service providers and subcontractors as part of its business. Trustmark also has substantial ongoing business relationships with partners and other third-parties and relies on certain third-parties to provide products and services necessary to maintain day-to-day operations. These types of third-party relationships are subject to increasingly demanding regulatory requirements and attention by regulators, including the FRB, OCC, CFPB and FDIC. Under regulatory guidance, Trustmark is required to apply stringent due diligence, conduct ongoing monitoring and maintain effective control over third-party service providers and subcontractors and other ongoing third-party business relationships. These regulatory expectations may change, and potentially become more rigorous in certain ways, due to an interagency effort to replace existing guidance on the risk management of third-party

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relationships with new guidance. Trustmark expects that the regulators will hold Trustmark responsible for deficiencies in its oversight and control of its third-party relationships and in the performance of the parties with which Trustmark has these relationships. Trustmark maintains a system of policies and procedures designed to ensure adequate due diligence is performed and to monitor vendor risks. While Trustmark believes these policies and procedures effectively mitigate risk, if the regulators conclude that Trustmark has not exercised adequate oversight and control over third-party service providers and subcontractors or other ongoing third-party business relationships or that such third-parties have not performed appropriately, Trustmark could be subject to enforcement actions, including civil monetary penalties or other administrative or judicial penalties or fines as well as requirements for customer remediation.

Operational Risks

There may be risks resulting from the extensive use of models in Trustmarks business.

Trustmark relies on statistical and quantitative models to measure risks and to estimate certain financial values. Models may be used in such processes as determining the pricing of various products, assessing potential acquisition opportunities, developing presentations made to market analysts and others, creating loans and extending credit, measuring interest rate and other market risks, predicting losses, assessing capital adequacy, calculating regulatory capital levels and estimating the fair value of financial instruments and balance sheet items. These models reflect assumptions that may not be accurate, particularly in times of market stress or other unforeseen circumstances. Even if these assumptions are adequate, the models may prove to be inadequate or inaccurate because of other flaws in their design or their implementation. If models for determining interest rate risk and asset-liability management are inadequate, Trustmark may incur increased or unexpected losses upon changes in market interest rates or other market measures. If models for determining expected credit losses are inadequate, the allowance for credit losses may not be sufficient to support future charge-offs. If models to measure the fair value of financial instruments are inadequate, the fair value of such financial instruments may fluctuate unexpectedly or may not accurately reflect what Trustmark could realize upon sale or settlement of such financial instruments. Any such failure in the analytical or forecasting models could have a material adverse effect on Trustmarks financial condition or results of operations.

Also, information Trustmark provides to its regulators based on poorly designed or implemented models could be inaccurate or misleading. Certain decisions that the regulators make, including those related to capital distributions and dividends to Trustmarks shareholders, could be adversely affected due to the regulators perception that the quality of Trustmarks models used to generate the relevant information is insufficient.

Trustmark could be required to write down goodwill and other intangible assets.

If Trustmark consummates an acquisition, a portion of the purchase price would generally be allocated to goodwill and other identifiable intangible assets. The amount of the purchase price that is allocated to goodwill and other intangible assets is determined by the excess of the purchase price over the net identifiable assets acquired. At December 31, 20234, goodwill and other identifiable intangible assets , 

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net were $387.234.7 million. Under current accounting standards, if Trustmark determines goodwill or intangible assets are impaired, Trustmark would be required to write down the carrying value of these assets. Trustmarks annual goodwill impairment evaluation performed during the fourth quarter of 20234 indicated no impairment of goodwill for any reporting segment. Management cannot provide assurance, however, that Trustmark will not be required to take an impairment charge in the future. Any impairment charge would have an adverse effect on Trustmarks shareholders equity and financial condition and could cause a decline in Trustmarks stock price.

Trustmark holds other real estate and may acquire and hold significant additional amounts, which could lead to increased operating expenses and vulnerability to additional declines in real property values.

As business necessitates, Trustmark forecloses on and takes title to real estate serving as collateral for loans. At December 31, 20234, Trustmark held $65.9 million of other real estate. The amount of other real estate held by Trustmark may increase in the future as a result of, among other things, business combinations, increased uncertainties in the housing market or increased levels of credit stress in residential real estate loan portfolios. Increased other real estate balances could lead to greater expenses as Trustmark incurs costs to manage, maintain and dispose of real properties as well as to remediate any environmental cleanup costs incurred in connection with any contamination discovered on real property on which Trustmark has foreclosed and to which Trustmark has taken title. As a result, Trustmarks earnings could be negatively affected by various expenses associated with other real estate owned, including personnel costs, insurance and taxes, completion and repair costs, valuation adjustments and other expenses associated with real property ownership, as well as by the funding costs associated with other real estate assets. The expenses associated with holding a significant amount of other real estate could have a material adverse effect on Trustmarks financial condition or results of operations.

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If Trustmark is required to repurchase a significant number of mortgage loans that it had previously sold, such repurchases could negatively affect earnings.

One of Trustmarks primary business operations is mortgage banking under which residential mortgage loans are sold in the secondary market under agreements that contain representations and warranties related to, among other things, the origination and characteristics of the mortgage loans. Trustmark may be required to either repurchase the outstanding principal balance of a loan or make the purchaser whole for the anticipated economic benefits of a loan if it is determined that the loan sold was in violation of representations or warranties made by Trustmark at the time of the sale, herein referred to as mortgage loan servicing putback expenses. Such representations and warranties typically include those made regarding loans that had missing or insufficient file documentation, loans that do not meet investor guidelines, loans in which the appraisal does not support the value and/or loans obtained through fraud by the borrowers or other third parties. Generally, putback requests may be made until the loan is paid in full. However, mortgage loans delivered to the Federal National Mortgage Association (FNMA) and the Federal Home Loan Mortgage Corporation (FHLMC) on or after January 1, 2013 are subject to the Representations and Warranties Framework, which provides that FNMA and FHLMC will not exercise their remedies, including a putback request, for breaches of certain selling representations and warranties if the mortgage loans satisfy certain criteria, such as payment history or quality control review.

Changes in retail distribution strategies and consumer behavior may adversely impact Trustmarks investments in premises, equipment, technology and other assets and may lead to increased expenditures to change its retail distribution channel.

Trustmark has significant investments in bank premises and equipment for its branch network. Advances in technology such as ecommerce, telephone, internet and mobile banking, and in-branch self-service technologies including interactive teller machines (ITMs) and other equipment, as well as an increasing customer preference for these other methods of accessing Trustmarks products and services, could decrease the value of its branch network, technology, or other retail distribution physical assets and may cause Trustmark to change its retail distribution strategy, close and/or sell certain branches or parcels of land held for development and restructure or reduce its remaining branches and work force. These actions could lead to losses on these assets or could adversely impact the carrying value of any long-lived assets and may lead to increased expenditures to renovate, reconfigure or close a number of Trustmarks remaining branches or to otherwise reform its retail distribution channel.

Trustmark may experience disruptions of its operating systems or breaches in its information system security.

Trustmark is dependent upon communications and information systems to conduct business as such systems are used to manage virtually all aspects of Trustmarks business. Trustmarks operations rely on the secure processing, storage and transmission of confidential and other information within its computer systems and networks. Any failure, interruption or breach in security of these systems could result in significant disruption to Trustmark's operations. Trustmark has taken protective measures, which are continuously monitored and modified as warranted; however, Trustmarks computer systems, software and networks may fail to operate properly or become disabled or damaged as a result of a number of factors, including events that are wholly or partially beyond Trustmarks control. There could be sudden increases in customer transaction volume; electrical, telecommunications or other major physical infrastructure outages; natural disasters; and events arising from local or larger scale political or social matters, including terrorist acts.

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Further, Trustmarks operational and security systems and infrastructure may be vulnerable to breaches and cybersecurity-related incidents including, but not limited to, attempts to access information, including customer and company information, malicious code, computer viruses and denial of service attacks that could result in unauthorized access, theft, misuse, loss, release or destruction of data (including confidential customer information), account takeovers, unavailability of service or other events. These types of threats may derive from human error, fraud or malice on the part of external or internal parties, or may result from accidental technological failure. If one or more of these events were to occur, Trustmarks or its customers confidential and other information would be jeopardized, or such an event could cause interruptions or malfunctions in Trustmarks or its customers or counterparties operations. Any failures related to upgrades and maintenance of Trustmark's technology and information systems could further increase its information and system security risk. Trustmark's increased use of cloud and other technologies, such as remote work technologies, also increases its risk of being subject to a cyber-attack. The risk of a security breach or disruption, particularly through cyber-attack or cyber intrusion, has increased as the number, intensity and sophistication of attempted attacks and intrusions from around the world have increased. Trustmark may be required to expend significant additional resources to modify its protective measures or to investigate and remediate vulnerabilities or other exposures in its computer systems and networks, and Trustmark may be subject to litigation and financial losses that are either not insured against or not fully covered through any insurance maintained by Trustmark. Any such losses, which may be difficult to detect, could adversely affect Trustmarks financial condition or results of operations. In addition, the occurrence of such a loss could expose Trustmark to reputational risk, the loss of customer business and additional regulatory scrutiny.

Security breaches in Trustmarks internet and mobile banking activities (myTrustmark) could further expose Trustmark to possible liability and reputational risk. Any compromise in security could deter customers from using Trustmarks internet and mobile banking services that involve the transmission of confidential information. Trustmark relies on standard internet security systems to provide the

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security and authentication necessary to effect secure transmission of data. However, these precautions may not protect Trustmarks systems from compromise or breaches of security, which could result in significant legal liability and significant damage to Trustmarks reputation and business.

Trustmark relies upon certain third-party vendors to provide products and services necessary to maintain day-to-day operations. Accordingly, Trustmarks operations are exposed to the risk that these vendors might not perform in accordance with applicable contractual arrangements or service level agreements or that the security of the third-party vendors computer systems, software and networks may be vulnerable to compromises that could impact information system security. Trustmark maintains a system of policies and procedures designed to monitor vendor risks. While Trustmark believes these policies and procedures effectively mitigate risk, the failure of an external vendor to perform in accordance with applicable contractual arrangements or service level agreements or any compromise in the security of an external vendors information systems could be disruptive to Trustmarks operations, which could have a material adverse effect on its financial condition or results of operations.

As of the date of this Annual Report on Form 10-K, Trustmark has seen no material adverse impact on its business or operations from cyber-attacks or events. Trustmark's customers, employees and third parties that it does business with have been, and will continue to be, targeted by parties using fraudulent e-mails and other communications in attempts to misappropriate passwords, bank account information or other personal information or to introduce viruses or other malware programs to its information systems, the information systems of its merchants or third-party service providers and/or its customers' personal devices, which are beyond Trustmark's security control systems. Though Trustmark endeavors to mitigate these threats through product improvements, use of encryption and authentication technology and customer and employee education, such cyber-attacks against Trustmark, its merchants, third-party service providers and customers remain a serious issue and have been successful in the past.

Although Trustmark makes significant efforts to maintain the security and integrity of its information systems and has implemented various measures to manage the risks of a security breach or disruption, there can be no assurance that its security efforts and measures will be effective or that attempted security breaches or disruptions would not be successful or damaging. Even well protected information, networks, systems and facilities remain potentially vulnerable to attempted security breaches or disruptions because the techniques used in such attempts are constantly evolving and generally are not recognized until launched against a target, and in some cases are designed not to be detected and, in fact, may not be detected. Accordingly, Trustmark may be unable to anticipate these techniques or to implement adequate security barriers or other preventative measures, and thus it is virtually impossible for Trustmark to entirely mitigate this risk. Furthermore, in the event of a cyber-attack, Trustmark may be delayed in identifying or responding to the attack, which could increase the negative impact of the cyber-attack on its business, financial condition and results of operations. A security breach or other significant disruption of Trustmark's information systems or those related to its customers, merchants or third-party vendors, including as a result of cyber-attacks, could (i) disrupt the proper functioning of its networks and systems and therefore its operations and/or those of its customers; (ii) result in the unauthorized access to, and destruction, loss, theft, misappropriation or release of confidential, sensitive or otherwise valuable information of Trustmark or its customers; (iii) result in a violation of applicable privacy, data breach and other laws, subjecting Trustmark to additional regulatory scrutiny and exposing it to civil litigation, enforcement actions, governmental fines and possible financial liability; (iv) require significant management attention and resources to remedy the damages that result; or (v) harm Trustmark's reputation or cause a decrease in the number of customers that choose to do business with

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Trustmark. The occurrence of any of the foregoing could have a material adverse effect on Trustmark's business, financial condition and results of operations.

Trustmark must utilize new technologies to deliver its products and services, which could require significant resources and expose Trustmark to additional risks, including cyber-security risks.

In order to deliver new products and services and to improve the productivity of existing products and services, the banking industry relies on rapidly evolving technologies. Trustmark continues to invest in technology to facilitate the ability of its customers to engage in financial transactions, and otherwise enhance the customer experience with respect to its products and services. Trustmarks ability to effectively utilize new technologies to address customer needs and create operating efficiencies could materially affect future prospects. Management cannot provide any assurances that Trustmark will be successful in utilizing such new technologies. Incorporation of new products and services, such as internet and mobile banking services, may require significant resources and expose Trustmark to additional risks, including cyber-security risks.

Trustmarks controls and procedures may fail or be circumvented.

Trustmarks internal controls, disclosure controls and procedures, and corporate governance policies and procedures are based in part on assumptions, and can provide only reasonable, not absolute, assurances that the objectives of the system are met. Any failure or circumvention of Trustmarks controls and procedures or failure to comply with regulations related to controls and procedures could have a material adverse effect on Trustmarks business, financial condition and results of operations.

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Trustmark may be subject to increased claims and litigation, which could result in legal liability and reputational damage.

Trustmark has been named from time to time as a defendant in litigation relating to its businesses and activities. Litigation may include claims for substantial compensatory or punitive damages or claims for indeterminate amounts of damages.

In recent years, a number of judicial decisions have upheld the right of borrowers to sue lending institutions on the basis of various evolving legal theories, collectively termed lender liability. Generally, lender liability is founded on the premise that a lender has either violated a duty, whether implied or contractual, of good faith and fair dealing owed to the borrower or has assumed a degree of control over the borrower resulting in the creation of a fiduciary duty owed to the borrower or its other creditors or shareholders.

 Substantial legal liability against Trustmark, including its subsidiaries, could materially adversely affect Trustmarks business, financial condition or results of operations, or cause significant harm to its reputation. TNB recently agreed to settlements relating to litigation involving the Stanford Financial Group and Adams/Madison Timber. For additional information regarding these settlements, see the section captioned Legal Proceedings in Note 16 - Commitments and Contingencies included in Part II. Item 8. - Financial Statements and Supplementary Data of this report.

Damage to Trustmarks reputation could have a significant negative impact on Trustmarks business.

Trustmarks ability to attract and retain customers, clients, investors, and highly-skilled management and employees is affected by its reputation. Significant harm to Trustmarks reputation can also arise from other sources, including employee misconduct, actual or perceived unethical or illegal behavior, litigation or regulatory outcomes, failing to deliver minimum or required standards of service and quality, compliance failures, disclosure of confidential information, significant or numerous failures, interruptions or breaches of its information systems and the activities of its clients, customers and counterparties, including vendors. Actions by the financial services industry generally or by certain members or individuals in the industry may have a significant adverse effect on Trustmarks reputation. Trustmark could also suffer significant reputational harm if it fails to properly identify and manage potential conflicts of interest. Management of potential conflicts of interests has become increasingly complex as Trustmark expands its business activities through more numerous transactions, obligations and interests with and among its clients. The actual or perceived failure to adequately address conflicts of interest could affect the willingness of clients to deal with Trustmark, which could adversely affect Trustmarks businesses.

Risk Related to Acquisition Activity

Potential acquisitions by Trustmark may disrupt Trustmarks business and dilute shareholder value.

Trustmark continuously monitors the market for merger or acquisition opportunities and, depending upon business and other considerations, may elect to pursue one or more such opportunities in the future. Any such merger or acquisition candidate would need to have a similar culture to Trustmark, have experienced management and possess either significant market presence or have potential for improved profitability through financial management, economies of scale or expanded services. Acquiring other banks, businesses, or branches involves various risks commonly associated with acquisitions, including: potential exposure to unknown or contingent liabilities of the target company, exposure to potential asset quality issues of the target company, difficulty and expense of integrating the operations and personnel of the target company, potential disruption to Trustmarks business, potential diversion of Trustmarks Managements time and attention, the possible loss of key employees and customers of the target company, difficulty in estimating the value of the target company and potential changes in banking or tax laws or regulations that may affect the target company. Acquisitions

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may involve the payment of a premium over book and market values, and, therefore, some dilution of Trustmarks tangible book value and net income per share of common stock may occur in connection with any future transaction. Furthermore, failure to realize the expected revenue projections, cost savings, increases in geographic or product presence, and/or other projected benefits from an acquisition could have a material adverse effect on Trustmarks financial condition or results of operations.

General Risk Factors

The stock price of financial institutions, like Trustmark, can be volatile.

The volatility in the stock prices of companies in the financial services industry, such as Trustmark, may make it more difficult for shareholders to resell Trustmark common stock at attractive prices in a timely manner. Trustmarks stock price can fluctuate significantly in response to a variety of factors, including factors affecting the financial industry as a whole, such as the bank failures in March 2023. The factors affecting financial stocks generally and Trustmarks stock price in particular include:

actual or anticipated variations in earnings;

changes in analysts recommendations or projections;

operating and stock performance of other companies deemed to be peers;

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perception in the marketplace regarding Trustmark, its competitors and/or the industry as a whole;

significant acquisitions or business combinations involving Trustmark or its competitors;

provisions in Trustmarks by-laws and articles of incorporation that may discourage takeover attempts, which may make Trustmark less attractive to a potential purchaser;

changes in government regulation;

failure to integrate acquisitions or realize anticipated benefits from acquisitions; and

volatility affecting the financial markets in general.

General market fluctuations, the potential for breakdowns on electronic trading or other platforms for executing securities transactions, industry factors and general economic and political conditions could also cause Trustmarks stock price to decrease regardless of operating results.

Changes in accounting standards may affect how Trustmark reports its financial condition and results of operations.

Trustmarks accounting policies and methods are fundamental to how Trustmark records and reports its financial condition and results of operations. From time to time, the FASB changes the financial accounting and reporting standards that govern the preparation of Trustmarks financial statements. The most recent economic recession resulted in increased scrutiny of accounting standards by regulators and legislators, particularly as they relate to fair value accounting principles. In addition, ongoing efforts to achieve convergence between generally accepted accounting principles (GAAP) and International Financial Reporting Standards may result in changes to GAAP. Any such changes can be difficult to predict and can materially affect how Trustmark records and reports its financial condition or results of operations. For additional details regarding recently adopted and pending accounting pronouncements, see Note 1  Significant Accounting Policies included in Part II. Item 8. - Financial Statements and Supplementary Data of this report.

Trustmark may not be able to attract or retain key employees.

Trustmarks success depends substantially on its ability to attract and retain skilled, experienced personnel. Competition for qualified candidates in the activities and markets that Trustmark serves is intense. While Trustmark invests significantly in the training and development of its employees, it is possible that Trustmark may not be able to retain key employees. If Trustmark were unable to retain its most qualified employees, its performance and competitive positioning could be materially adversely affected.

Natural disasters, such as hurricanes, could have a significant negative impact on Trustmarks business.

Many of Trustmarks loans are secured by property or are made to businesses in or near the Gulf Coast regions of Alabama, Florida, Mississippi and Texas, which are often in the path of seasonal hurricanes. Natural disasters, such as hurricanes, could have a significant negative impact on the stability of Trustmarks deposit base, the ability of borrowers to repay outstanding loans and the value of collateral securing loans, and could cause Trustmark to incur material additional expenses. Although Management has established disaster recovery policies and procedures, the occurrence of a natural disaster, especially if any applicable insurance coverage is not adequate to

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enable Trustmarks borrowers to recover from the effects of the event, could have a material adverse effect on Trustmarks financial condition or results of operations.

Expectations around Environmental, Social and Governance (ESG) practices as well as climate change and related legislative and regulatory initiatives could adversely affect Trustmarks business and results of operations, including indirectly through impact to its customers.

Companies are facing increased scrutiny from customers, regulators and other stakeholders with respect to their ESG practices and disclosures. Institutional investors, and investor advocacy groups, in particular, are increasingly focused on these matters and expectations in many of these areas can vary widely. In addition, increased ESG related compliance costs could result in increases to Trustmarks overall operational costs. Failure to adapt to or comply with regulatory requirements or investor or stakeholder expectations and standards, and fluctuations in these standards, could negatively impact Trustmarks reputation, ability to do business with certain partners and its stock price. New government regulations could also result in new or more stringent forms of ESG oversight and expanding mandatory and voluntary reporting, diligence and disclosure.

In addition to regulatory and investor expectations on environmental matters in general, the current and anticipated effects of climate change are creating an increasing level of concern for the state of the global environment. As a result, political and social attention to the issue of climate change has increased. In recent years, governments across the world have entered into international agreements to attempt to reduce global temperatures, in part by limiting greenhouse gas emissions. The United States Congress, state legislatures and

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federal and state regulatory agencies have continued to propose and advance numerous legislative and regulatory initiatives seeking to mitigate the effects of climate change. These agreements and measures may result in the imposition of taxes and fees, the required purchase of emission credits and the implementation of significant operational changes, each of which may require businesses to expend significant capital and incur compliance, operating, maintenance and remediation costs. Consumers and businesses also may change their behavior on their own as a result of these concerns.

It is not possible to predict how climate change may impact Trustmarks financial condition and operations; however, Trustmark operates in areas where its business and the activities of its customers could be impacted by the effects of climate change. The effects of climate change may include increased frequency or severity of weather-related events, such as severe storms, hurricanes, flooding and droughts and rising sea levels. These effects can disrupt business operations, damage property, devalue assets and change customer and business preferences, which may adversely affect borrowers, increase credit risk and reduce demand for Trustmarks products and services. Trustmark and its customers will need to respond to new laws and regulations as well as consumer and business preferences resulting from climate change concerns. Trustmark and its customers may face cost increases, asset value reductions, operating process changes and the like. The impact to Trustmarks customers will likely vary depending on their specific attributes, including reliance on or role in carbon intensive activities. In addition, Trustmark could face reductions in creditworthiness on the part of some customers or in the value of assets securing loans. Trustmarks efforts to take these risks into account may not be effective in protecting it from the negative impact of new laws and regulations or changes in consumer or business behavior and could have a material adverse effect on Trustmarks financial condition and results of operations.