Exhibit 99.1

TRICO BANCSHARES ANNOUNCES QUARTERLY RESULTS

CHICO, Calif. – (July 25, 2013) – TriCo Bancshares (NASDAQ: TCBK) (the “Company”), parent company of Tri Counties Bank (the “Bank”), today announced earnings of $6,325,000, or $0.39 per diluted share, for the three months ended June 30, 2013. These results compare to earnings of $5,321,000, or $0.33 per diluted share reported by the Company for the three months ended June 30, 2012.

Total assets of the Company increased $62,313,000 (2.5%) to $2,587,931,000 at June 30, 2013 from $2,525,618,000 at June 30, 2012. Total loans increased $99,558,000 (6.4%) to $1,652,040,000 at June 30, 2013 from $1,552,482,000 at June 30, 2012. Total investment securities increased $10,313,000 (5.1%) to $213,162,000 at June 30, 2013 from $202,849,000 at June 30, 2012. Total deposits increased $100,925,000 (4.7%) to $2,266,702,000 at June 30, 2013 from $2,165,777,000 at June 30, 2012. Other borrowings decreased $54,256,000 (89.2%) to $6,575,000 at June 30, 2013 from $60,831,000 at June 30, 2012.

The following is a summary of the components of the Company’s consolidated net income for the periods indicated:

The following table shows the components of net interest income and net interest margin on a fully tax-equivalent (FTE) basis for the periods indicated:

ANALYSIS OF CHANGE IN NET INTEREST MARGIN ON EARNING ASSETS

(unaudited, dollars in thousands)

Net interest income (FTE) during the second quarter of 2013 decreased $1,319,000 (5.1%) from the same period in 2012 to $24,679,000. The decrease in net interest income (FTE) was due primarily to a 79 basis point decrease in average yield on loans that was partially offset by a $74,505,000 increase in the average balance of loans, and a $54,704,000 decrease in the average balance of other borrowings. The 79 basis point decrease in average loan yields reduced net interest income by $3,163,000 from the year ago period. The increase in average loan balances added $1,254,000 to net interest income, and the decrease in average other borrowings added $528,000 to net interest income when compared to the year ago period. Accretion of loan purchase discounts totaling $1,676,000 and $2,385,000 are included in net interest income for the three months ended June, 2013 and 2012, respectively. The Company purchased $60,647,000 of residential real estate mortgage loans during the second quarter of 2013.

Loans acquired through purchase or acquisition of other banks are classified as Purchased Not Credit Impaired (PNCI), Purchased Credit Impaired – cash basis (PCI – cash basis), or Purchased Credit Impaired – other (PCI – other). Loans not acquired in an acquisition or otherwise “purchased” are classified as “originated”. Often, such purchased loans are purchased at a discount to face value, and part of this discount is accreted into (added to) interest income over the remaining life of the loan. Generally, as time goes on, the effect of this discount accretion becomes less and less as these purchased loans mature or payoff early. Further details regarding interest income from loans, including fair value discount accretion, may be found under the heading “Supplemental Loan Interest Income Data” in the Consolidated Financial Data table at the end of this announcement.

The Company provided $614,000 for loan losses in the second quarter of 2013 versus a benefit of $1,108,000 in the first quarter of 2013, and a $3,371,000 provision for loan losses in the second quarter of 2012. The level of provision for loan losses during the second quarter of 2013 was due primarily to a decrease in the required allowance for loan losses as of June 30, 2013 when compared to the required allowance for loan losses as of March 31, 2013 less net charge-offs during the three months ended June 30, 2013, and the effect of a change in the methodology for calculating the allowance for loan losses that occurred during the three months ended June 30, 2013. The decrease in the required allowance for loan losses during the quarter ended June 30, 2013 was due primarily to reduced impaired loans, improvements in estimated cash flows and collateral values for the remaining and new impaired loans, and reductions in historical loss factors that, in part, determine the required loan loss allowance for performing loans in accordance with the Company’s allowance for loan losses methodology.

During the three months ended June 30, 2013, the Company modified its loss migration analysis methodology used in its allowance for loan loss calculation. When the Company originally established its loss migration analysis methodology during the quarter ended March 31, 2012, it reviewed the loss experience of each quarter over the most recent three years in order to calculate an annualized loss rate by loan category and risk rating. The use of three years of loss experience data was originally used because that was the extent of the detailed loss data by loan category and risk rating that was available at the time. This three year historical look-back period was used until this most recent quarter ended June 30, 2013. Starting with the quarter ended June 30, 2013 the Company will review all available detailed loss experience data, and not limit it to the most recent three years of historical loss data. This change in methodology resulted in the allowance for loan losses as of June 30, 2013 being $1,314,000 more than it would have been without this change in methodology. Excluding the effect of this change in allowance methodology, the provision for loan losses during the three months ended June 30, 2013 would have been a benefit of $700,000.

The following table presents the key components of noninterest income for the periods indicated:

Noninterest income decreased $446,000 (4.2%) to $10,131,000 in the three months ended June 30, 2013 when compared to the three months ended June 30, 2012. The decrease in noninterest income was due primarily to a $976,000 decrease in change in indemnification asset to a loss of $314,000, and a $600,000 decrease in gain on life insurance death benefit, included in other noninterest income, to zero that were partially offset by a $655,000 increase in change in value of mortgage servicing rights to $191,000, a $353,000 increase in gain on sale of loans to $1,590,000, and a $311,000 increase in gain on sale of foreclosed assets to $615,000. The decrease in change in indemnification asset was due to increased real estate collateral values that resulted in lower expected losses on covered impaired loans. The increase in change in value of mortgage servicing rights was due to a sharp increase in mortgage rates that occurred near the end of the quarter ended June 30, 2013 that reduced the rate of mortgage refinancing that in turn increased the expected future life and cash flow stream of our existing mortgage servicing portfolio. The increase in gain on sale of loans was due to decreased mortgage rates that existed for much of the quarter ended June 30, 2013 when compared to the quarter ended June 30, 2012, and our focus of additional resources in this area when compared to the year-ago quarter. The increase in gain on sale of foreclosed assets was due to increased real estate values.

The following table presents the key components of the Company’s noninterest expense for the periods indicated:

Salary and benefit expenses increased $400,000 (3.2%) to $12,890,000 during the three months ended June 30, 2013 compared to the three months ended June 30, 2012. Base salaries increased $235,000 (2.8%) to $8,508,000 due mainly to annual merit increases. Incentive and commission related salary expenses decreased $48,000 (3.6%) to $1,299,000 due primarily to decreases in production related incentives. Benefits expense, including retirement, medical and workers’ compensation insurance, and taxes, increased $213,000 (7.4%) to $3,083,000 due primarily to increased health and workers’ compensation insurance expenses.

Other noninterest expenses decreased $1,258,000 (10.6%) to $10,619,000 during the three months ended June 30, 2013 when compared to the three months ended June 30, 2012. The decrease in other noninterest expense was due primarily a $562,000 (44.2%) decrease in the provision for, and expenses related to, foreclosed assets, a $448,000 (51.9%) decrease in advertising and marketing expense, and a $317,000 (10.6%) decrease in occupancy and equipment expenses. The decrease in foreclosed asset provision and expenses was due to increased property values and a reduction in foreclosed assets from $12,743,000 at June 30, 2012 to $5,054,000 at June 30, 2013. The decrease in advertising and marketing expense from the year ago period was due to cost savings efforts in this area. The decrease in occupancy and equipment expense was primarily due to reduced furniture and equipment expense as the Bank focused on its new campus and operations center that came into service at the end of June 2013.

In addition to the historical information contained herein, this press release may contain certain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. The reader of this press release should understand that all such forward-looking statements are subject to various uncertainties and risks that could affect their outcome. The Company’s actual results could differ materially from those suggested by such forward-looking statements. Factors that could cause or contribute to such differences include, but are not limited to, variances in the actual versus projected growth in assets, return on assets, interest rate fluctuations, economic conditions in the Company’s primary market area, demand for loans, regulatory and accounting changes, loan

losses, expenses, rates charged on loans and earned on securities investments, rates paid on deposits, competition effects,

fee and other noninterest income earned as well as other factors detailed in the Company’s reports filed with the Securities and Exchange Commission which are incorporated herein by reference, including the Form 10-K for the year ended December 31, 2012. These reports and this entire press release should be read to put such forward-looking statements in context and to gain a more complete understanding of the uncertainties and risks involved in the Company’s business. Any forward-looking statement may turn out to be wrong and cannot be guaranteed. The Company does not intend to update any of the forward-looking statements after the date of this release.

TriCo Bancshares and Tri Counties Bank are headquartered in Chico, California. Tri Counties Bank has a 38-year history in the banking industry. It operates 41 traditional branch locations and 25 in-store branch locations in 23 California counties. Tri Counties Bank offers financial services and provides a diversified line of products and services to consumers and businesses, which include demand, savings and time deposits, consumer finance, online banking, mortgage lending, and commercial banking throughout its market area. It operates a network of 72 ATMs and a 24-hour, seven days-a-week telephone customer service center. Brokerage services are provided by the Bank’s investment services affiliate, Raymond James Financial Services, Inc. For further information please visit the Tri Counties Bank web site at http://www.tricountiesbank.com.

TRICO BANCSHARES—CONSOLIDATED FINANCIAL DATA

(Unaudited. Dollars in thousands, except share data)

TRICO BANCSHARES—CONSOLIDATED FINANCIAL DATA

(Unaudited. Dollars in thousands)