Exhibit 99.1

TRICO BANCSHARES ANNOUNCES QUARTERLY RESULTS

CHICO, Calif. – (April 30, 2012) – TriCo Bancshares (NASDAQ: TCBK) (the “Company”), parent company of Tri Counties Bank (the “Bank”), today announced a $1,131,000 (40.4%) increase in earnings from $2,800,000 for the three months ended March 31, 2011 to $3,931,000 for the three months ended March 31, 2012. Diluted earnings per share for the three months ended March 31, 2012 were $0.25 compared to diluted earnings per share of $0.17 for the three months ended March 31, 2011.

Total assets of the Company increased $337,170,000 (15.4%) to $2,532,908,000 at March 31, 2012 from $2,195,738,000 at March 31, 2011. Total loans of the Company increased $123,425,000 (8.9%) to $1,511,085,000 at March 31, 2012 from $1,387,660,000 at March 31, 2011. The increase in loans is due to $167,484,000 of loans acquired in the acquisition of the banking operations of Citizens Bank of Northern California (“Citizens”) on September 23, 2011 that was partially offset by charge offs and net loan payoffs. Total deposits of the Company increased $309,834,000 (16.7%) to $2,169,746,000 at March 31, 2012 from $1,859,912,000 at March 31, 2011. The increase in deposits is mainly due to $239,899,000 of deposits acquired in the Citizens acquisition.

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

Included in the Company’s results for the three month period ended March 31, 2012 is the acquisition by Tri Counties Bank of the banking operations of Citizens Bank of Northern California, Nevada City, California from the FDIC under a whole bank purchase and assumption agreement without loss sharing on September 23, 2011. The assets acquired and liabilities assumed in the Citizens acquisition have been accounted for under the acquisition method of accounting (formerly the purchase method). Loans acquired through the Citizens acquisition 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”. 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 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, in thousands)

Net interest income (FTE) during the first quarter of 2012 increased $3,314,000 (15.2%) from the same period in 2011 to $25,101,000. The increase in net interest income (FTE) was due to a $131,205,000 (9.4%) increase in average balance of loans and a 31 basis point increase in average yield on loans, both of which are mainly due to the Citizens acquisition in September 2011. Also contributing to the increase in net interest margin during this first quarter of 2012 was a 17 basis point decrease in the cost of deposits from 0.39% during the three months ended March 31, 2011 to 0.22% during the three months ended March 31, 2012. Despite these positive factors noted above, the Company’s ability to deploy excess deposits into some interest-earning asset other than short-term low-yield interest-earning cash at the Federal Reserve Bank has been limited. This limitation is the result of weak loan demand and investment yields that have been unattractive given their interest rate risk profile.

The Company provided $3,996,000 for loan losses in the first quarter of 2012 versus $5,429,000 in the fourth quarter of 2011 and $7,001,000 in the first quarter of 2011. In accordance with industry guidance, related to real estate 1-4 family junior lien mortgages, issued by bank regulators during the first quarter of 2012, $6,541,000 of performing junior liens were reclassified from a Pass rating to a rating of Special Mention due to concerns regarding the performance of the associated priority liens. This reclassification resulted in additional provisions for loan losses of $1,596,000.

The allowance for loan losses decreased $462,000 from $45,914,000 at December 31, 2011 to $45,452,000 at March 31, 2012. The decreases in provision for loan losses and in the allowance for loan and lease losses during the first quarter of 2012 were primarily the result of a decrease in nonperforming loans that was partially offset by the increased provision related to real estate 1-4 family junior lien mortgages noted above.

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

Noninterest income decreased $1,085,000 (11.6%) to $8,265,000 in the three months ended March 31, 2012 when compared to the three months ended March 31, 2011. The decrease in noninterest income was primarily due to a $2,045,000 decrease in change in indemnification asset to a negative $353,000, and a $558,000 decrease in gain on sale of foreclosed assets, that were partially offset by a $925,000 increase in gain on sale of loans, and a $459,000 increase in commissions on sale of nondeposit investment products (NDIP). The decrease in change in indemnification offset is further offset by a reduced provision for loan losses and increased interest income related to covered loans, and is related to improved credit metrics of covered loans. The increase in gain on sale of loans is due to increased residential real estate loan refinance activity and our focus to service that activity. The increase in commissions on sale of NDIP is due to our application of additional resources in that area.

Salary and benefit expenses increased $1,969,000 (18.2%) to $12,762,000 during the three months ended March 31, 2012 compared to the three months ended March 31, 2011. Base salaries increased $1,155,000 (16.5%) to $8,159,000 during the three months ended March 31, 2012. The increase in base salaries was mainly due to a 9.1% increase in average full time equivalent staff to 731 and annual merit increases when compared to the three months ended March 31, 2011. The increase in full time equivalent staff is mainly due to Citizens acquisition on September 23, 2011. Incentive and commission related salary expenses increased $459,000 (50.1%) to $1,375,000 during three months ended March 31, 2012 due primarily to increases in production related incentives and incentives tied to net income. Benefits expense, including retirement, medical and workers’ compensation insurance, and taxes, increased $355,000 (12.4%) to $3,228,000 during the three months ended March 31, 2012 primarily due to the increase in average full time equivalent staff noted above.

Other noninterest expenses increased $1,275,000 (14.4%) to $10,153,000 during the three months ended March 31, 2012 when compared to the three months ended March 31, 2011. Changes in the various categories of other noninterest expense are reflected in the table below. The changes are indicative of the Citizens acquisition, and the economic environment which has led to increases, or fluctuations, in professional loan collection expenses, provision for foreclosed asset losses, and foreclosed asset expenses.

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

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, 2011. 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 37-year history in the banking industry. It operates 41 traditional branch locations and 27 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 76 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)