TriCo Bancshares (the “Company” or “we”) is a California corporation organized to act as a bank holding company for Tri Counties Bank (the “Bank”). The Company and the Bank are headquartered in Chico, California. The Bank is a California-chartered bank that is engaged in the general commercial banking business in 31 California counties. The consolidated financial statements are prepared in accordance with accounting policies generally accepted in the United States of America and general practices in the banking industry. All adjustments necessary for a fair presentation of these consolidated financial statements have been included and are of a normal and recurring nature. The financial statements include the accounts of the Company. All inter-company accounts and transactions have been eliminated in consolidation.

The Company maintains two capital subsidiary business trusts (collectively, the “Capital Trusts”), both organized by the Company. For financial reporting purposes, the Company’s investments in the Capital Trusts of $1.2 million are accounted for under the equity method and, accordingly, are not consolidated and are included in other assets on the consolidated balance sheets.

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires Management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission. These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025 (the “2025 Annual Report”). The Company believes that the disclosures made are adequate to make the information not misleading.

The Company grants agribusiness, commercial, consumer, and residential loans to customers located throughout California. The Company has a diversified loan portfolio within the business segments located in this geographical area. While our Chief Executive Officer, the chief operating decision-maker (CODM), may monitor the revenue streams of the various products and services, operations are managed, financial performance is evaluated, and decisions are generally made on a Company-wide basis. Discrete financial information is not available other than on a Company-wide basis. Accordingly, operations are considered by management to be aggregated in one reportable operating segment.

For the purpose of describing the geographical location of the Company’s operations, the Company has defined northern California as that area of California north of, and including, Stockton to the east and San Jose to the west; central California as that area of the state south of Stockton and San Jose, to and including, Bakersfield to the east and San Luis Obispo to the west; and southern California as that area of the state south of Bakersfield and San Luis Obispo.

Loans that Management has the intent and ability to hold for the foreseeable future or until maturity or payoff are reported at the principal amount outstanding, net of deferred loan fees and costs. Loan origination and commitment fees and certain direct loan origination costs are deferred, and the net amount is amortized as an adjustment to the related loan’s yield over the actual life of the loan. Loans on which the accrual of interest has been discontinued are designated as nonaccrual loans.

Loans are placed in nonaccrual status when reasonable doubt exists as to the full, timely collection of interest or principal, or a loan becomes contractually past due by 90 days or more with respect to interest or principal and is not well secured and in the process of collection. When a loan is placed on nonaccrual status, all interest previously accrued but not collected is reversed. Income on such loans is then recognized only to the extent that cash is received and where the future collection of principal is considered probable. Interest accruals

The Company measures expected credit losses on HTM debt securities on a collective basis by major security type, then further disaggregated by sector and bond rating. Accrued interest receivable on HTM debt securities was considered insignificant at June 30, 2026 and December 31, 2025 and is therefore excluded from the estimate of credit losses. The estimate of expected credit losses considers historical credit loss information that is adjusted for current conditions and reasonable and supportable forecasts based on current and expected changes in credit ratings and default rates. Based on the implied guarantees of the U. S. Government or its agencies related to certain of these investment securities, and the absence of any historical or expected losses, substantially all qualify for a zero loss assumption. Management has separately evaluated its HTM investment securities from obligations of state and political subdivisions utilizing the historical loss data represented by similar securities over a period of time spanning nearly 50 years. As a result of this evaluation, management determined that the expected credit losses associated with these securities is not significant for financial reporting purposes and therefore, no allowance for credit losses has been recognized for any period reported.

The Company evaluates AFS debt securities in an unrealized loss position to determine whether the decline in the fair value below the amortized cost basis (impairment) is due to credit-related factors or noncredit-related factors. Any impairment that is not credit related is recognized in other comprehensive income, net of applicable taxes. Credit-related impairment is recognized as an allowance for credit losses on the balance sheet, limited to the amount by which the amortized cost basis exceeds the fair value, with a corresponding adjustment to earnings. Both the allowance for credit losses and the adjustment to net income may be reversed if conditions change. However, if the Company intends to sell an impaired available for sale debt security or more likely than not will be required to sell such a security before recovering its amortized cost basis, the entire impairment amount is recognized in earnings with a corresponding adjustment to the security's amortized cost basis. In evaluating available for sale debt securities in unrealized loss positions for impairment and the criteria regarding its intent or requirement to sell such securities, the Company considers the extent to which fair value is less than amortized cost, whether the securities are issued by the federal government or its agencies, whether downgrades by bond rating agencies have occurred, and the results of reviews of the issuers' financial condition, among other factors. Changes in the allowance for credit losses are recorded as provision for (or reversal of) credit loss expense. Losses are charged against the ACL when management believes the uncollectability of an available for sale debt security is confirmed or when either of the criteria regarding intent or requirement to sell is met. No security credit losses were recognized during the six-month periods ended June 30, 2026 and 2025, respectively.

Loans that management has the intent and ability to hold until maturity or payoff are reported at principal amount outstanding, net of deferred loan fees and costs. Loans are placed in nonaccrual status when reasonable doubt exists as to the full, timely collection of interest or principal, or a loan becomes contractually past due by 90 days or more with respect to interest or principal and is not well secured and in the process of collection. When a loan is placed on nonaccrual status, all interest previously accrued but not collected is reversed against interest income. Income on such loans is then recognized only to the extent that cash is received and where the future collection of principal is considered probable. Interest accruals are resumed on such loans only when they are brought fully current with respect to interest and principal and when, in the judgment of Management, the loan is estimated to be fully collectible as to both principal and interest. Accrued interest receivable is not included in the calculation of the allowance for credit losses.

The Company performs an ACL evaluation on its loan and lease portfolio and its HTM and AFS securities portfolios. The ACL on loan and lease portfolio and HTM securities are provided through an expected loss methodology referred to as CECL methodology. The ACL on AFS securities is provided when a credit loss is deemed to have occurred for securities which the Company does not intend to sell or is not required to sell. The CECL methodology also applies to credit exposures on off-balance-sheet loan commitments.

The ACL is a valuation account that is deducted from the loan's amortized cost basis to present the net amount expected to be collected on the loans. Loans are charged off against the allowance when management believes the recorded loan balance is confirmed as uncollectible. Expected recoveries do not exceed the aggregate of amounts previously charged-off and expected to be charged-off. Regardless of the determination that a charge-off is appropriate for financial accounting purposes, the Company manages its loan portfolio by continually monitoring, where possible, a borrower's ability to pay through the collection of financial information, delinquency status, borrower discussion and the encouragement to repay in accordance with the original contract or modified terms, if appropriate.

The ACL consists of two primary components: (1) the determination of an ACL for loans that are individually identified and analyzed and (2) establishment of an ACL for loans collectively analyzed. To determine the collectively analyzed portion of the ACL, the Company identified various portfolio segments based on loan attributes such as, but not limited to; collateral type and loan purpose or use, to ensure loans with similar risk characteristics are measured on a collective basis. The Company utilizes three different loss model configurations and assigned each of the portfolio segments to one of the three loss model configurations. Historical credit loss experience for financial institutions nationwide, paired with relevant forecasts of macroeconomic conditions, forms the basis for the estimate of expected credit losses amongst the collectively analyzed loan portfolio. Further, each of the three loss model configurations utilized by the Company incorporate unique inputs, such as the following:

After quantitative considerations, management evaluates the need for additional qualitative adjustments that consider the expected impact of certain factors not fully captured in the quantitative and macroeconomic reserve calculations. These qualitative adjustments may apply to the collectively analyzed pool as a whole, one or more of the three loss models, or to one or more of the loan portfolio segments.

Purchased financial assets with a more-than-insignificant amount of credit deterioration since origination (“PCD assets”) that are measured at amortized cost, the initial allowance for credit losses is added to the purchase price rather than reported as a provision for credit losses. Subsequent changes in the allowance for credit losses on PCD assets are recognized through the provision for credit losses.

For HTM debt securities, the Company measures expected credit losses on held-to-maturity debt securities on a collective basis by major security type, then further disaggregated by sector and bond rating. Accrued interest receivable on held-to-maturity (HTM) debt securities is excluded from the estimate of credit losses. The estimate of expected credit losses considers historical credit loss information that is adjusted for current condition and reasonable and supportable forecasts based on current and expected changes in credit ratings and default rates. Nearly all of the Company's HTM securities are issued by the U. S. Government entities or agencies, and based on the absence of any historical or expected losses, all qualify for a zero loss assumption. Therefore, no allowance for credit losses has been recognized during the six months ended June 30, 2026 and 2025, respectively.

The Company evaluates available for sale debt securities in an unrealized loss position to determine whether the decline in the fair value below the amortized cost basis (impairment) is due to credit-related factors or noncredit-related factors. Any impairment that is not credit related is recognized in other comprehensive income, net of applicable taxes. Credit-related impairment is recognized as an allowance for credit losses on the balance sheet, limited to the amount by which the amortized cost basis exceeds the fair value, with a corresponding adjustment to earnings. Both the allowance for credit losses and the adjustment to net income may be reversed if conditions change. However, if the Company intends to sell an impaired available for sale debt security or more likely than not will be required to sell such a security before recovering its amortized cost basis, the entire impairment amount is recognized in earnings with a corresponding adjustment to the security's amortized cost basis. In evaluating available for sale debt securities in unrealized loss positions for impairment and the criteria regarding its intent or requirement to sell such securities, the Company considers the extent to which fair value is less than amortized cost, whether the securities are issued by the federal government or its agencies, whether downgrades by bond rating agencies have occurred, and the results of reviews of the issuers' financial condition, among other factors. Changes in the allowance for credit losses are recorded as provision for (or reversal of) credit loss expense. Losses are charged against the ACL when management believes the uncollectability of an available for sale debt security is confirmed or when either of the criteria regarding intent or requirement to sell is met. No security credit losses were recognized during the six months ended June 30, 2026 and 2025, respectively.

The Company is required to include unfunded commitments that are expected to be funded in the future within the allowance for credit loss calculation, other than those that are unconditionally cancellable. To arrive at that reserve, the reserve percentage determined within the same three loss models described above is applied to the unused portion of the expected commitment balance and is multiplied by the expected funding rate. To determine the expected funding rate, the Company uses a historical utilization rate for each segment. The allowance for credit losses for off-balance-sheet credit risk exposures is reported in other liabilities in the condensed consolidated balance sheets.

Standard

Summary of Guidance

Effects on financial statements

ASU 2024-03: Disaggregation of Income Statement Expenses (DISE)

•Requires additional disclosure of the nature of expenses included in the income statement to be presented in a tabular format in the footnotes to the financial statements.

ASU 2024-03 is effective for annual periods beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027. This standard is not expected to have a material impact on the Company’s financial statements.