Exhibit 99.1

TRICO BANCSHARES ANNOUNCES QUARTERLY AND YEAR END RESULTS

CHICO, Calif. – (January 30, 2015) – TriCo Bancshares (NASDAQ: TCBK) (the “Company”), parent company of Tri Counties Bank, today announced earnings of $5,650,000, or $0.25 per diluted share, for the three months ended December 31, 2014. For the three months ended December 31, 2013 the Company reported earnings of $5,236,000, or $0.32 per diluted share. Diluted earnings per share for the years ended December 31, 2014 and 2013 were $1.46 and $1.69, respectively, on earnings of $26,108,000 and $27,399,000, respectively.

On October 3, 2014, TriCo completed its acquisition of North Valley Bancorp. Based on an exchange ratio of 0.9433 shares of TriCo common stock for each share of North Valley Bancorp common stock, North Valley Bancorp shareholders received a total of 6,575,550 shares of TriCo common stock and $6,823 of cash in-lieu of fractional shares for all of the common shares of North Valley Bancorp. The 6,575,550 shares of TriCo common stock issued to North Valley Bancorp shareholders represents, on a pro forma basis, 28.9% of the 22,714,964 shares of the combined Company’s outstanding common stock on October 3, 2014. Based on TriCo’s closing stock price of $23.01 on October 3, 2014, North Valley Bancorp shareholders received consideration valued at $151,310,000 or approximately $21.71 for each of the 6,971,105 shares of North Valley Bancorp common stock outstanding immediately prior to the merger. TriCo appointed three North Valley Bancorp directors to TriCo’s board upon closing of the merger on October 3, 2014 as contemplated by the merger agreement.

North Valley Bancorp was headquartered in Redding, California, and was the parent of North Valley Bank that had approximately $935 million in assets and 22 commercial banking offices in Shasta, Humboldt, Del Norte, Mendocino, Yolo, Sonoma, Placer and Trinity Counties in Northern California at June 30, 2014. In connection with the acquisition, North Valley Bank was merged into Tri Counties Bank.

On October 25, 2014, North Valley Bank’s electronic customer service and other data processing systems were converted into Tri Counties Bank’s systems. Between January 7, 2015 and January 21, 2015, four Tri Counties Bank branches and four former North Valley Bank branches were consolidated into other Tri Counties Bank or other former North Valley Bank branches.

Beginning on October 4, 2014, the effect of revenue and expenses from the operations of North Valley Bancorp, and the TriCo Bancshares common shares issued in consideration of the merger are included in the results of the Company.

Included in the results of the Company for the three months ended December 31, 2014 and 2013 were $3,590,000 and $312,000, respectively, of nonrecurring noninterest expenses related to the merger with North Valley Bancorp of which $438,000 and $250,000, respectively, were not deductible for income tax purposes. Excluding these nonrecurring merger related expenses, but including the revenue and other expenses from the operations of North Valley Bancorp from October 4, 2014 to December 31, 2014, diluted earnings per share for the three months ended December 31, 2014 and 2013 would have been $0.35 and $0.34, respectively, on earnings of $7,916,000 and $5,522,000, respectively.

Included in the results of the Company for the years ended December 31, 2014 and 2013 were $4,858,000 and $312,000, respectively, of nonrecurring noninterest expenses related to the merger with North Valley Bancorp of which $1,269,000 and $250,000, respectively, were not deductible for income tax purposes. Excluding these nonrecurring merger related expenses, but including the revenue and other expenses from the operations of North Valley Bancorp from October 4, 2014 to December 31, 2014, diluted earnings per share for the years ended December 31, 2014 and 2013 would have been $1.64 and $1.71, respectively, on earnings of $29,459,000 and $27,685,000, respectively.

The following is a summary of certain of the Company’s consolidated assets and deposits as of the dates indicated:

The assets acquired and liabilities assumed from North Valley Bancorp were accounted for in accordance with ASC 805 “Business Combinations,” using the acquisition method of accounting and were recorded at their estimated fair values on the October 3, 2014 acquisition date; and its results of operations are included in the Company’s consolidated statements of income since that date. The fair value estimates of assets acquired and liabilities assumed are considered provisional, as additional analysis will be performed on certain assets and liabilities in which fair values are primarily determined through the use of inputs that are not observable from market-based information. The Company may further adjust the provisional fair values for a period of up to one year from the date of the acquisition. The excess of the fair value of consideration transferred over total identifiable net assets was recorded as goodwill. The goodwill arising from the acquisition consists largely of the synergies and economies of scale expected from combining the operations of the Company and North Valley Bancorp. None of the goodwill is deductible for income tax purposes as the acquisition was accounted for as a tax-free exchange. The assets and liabilities that continue to be provisional include loans, intangible assets, OREO, deferred tax assets, accrued assets and liabilities, and the residual effects that the adjustments would have on goodwill.

The following table discloses the calculation of the fair value of consideration transferred, the total identifiable net assets acquired and the resulting goodwill relating to the North Valley Bancorp acquisition:

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 fourth quarter of 2014 increased $8,617,000 (32.6%) from the same period in 2013 to $35,052,000. The increase in net interest income (FTE) was due primarily to a $1,001,302,000 (39.9%) increase in the average balance of interest earning assets to $3,512,620,000, and the use of fed funds sold to purchase higher yielding investments throughout 2014 that were partially offset by a 47 basis point decrease in the average yield on loans to 5.46% and a 36 basis point decrease in the average yield on investments to 2.77% during the three months ended December 31, 2014 when compared to the year ago quarter. The acquisition of North

Valley Bancorp contributed approximately $6,730,000, to interest income from loans, including approximately $480,000 of loan purchase discount accretion, and $1,310,000 to interest income from investments during the quarter ended December 31, 2014. For the quarter ended December 31, 2014, the average yields on the acquired North Valley Bancorp loans, including the effect of loan purchase discount accretion, and investments were approximately 5.68% and 2.72% (FTE), respectively. During the quarter ended December 31, 2014, the Company did not acquire any loans other than the North Valley Bancorp loans.

Loans acquired through purchase or acquisition of other banks are classified by the Company 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 decreases as these purchased loans mature or pay off 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 press release.

The Company benefited from a $1,421,000 reversal of provision for loan losses during the three months ended December 31, 2014 versus a $172,000 provision for loan losses during the three months ended December 31, 2013. In general, the credit quality of the Company’s loans continued to improve during the quarter ended December 31, 2014 due to improvements in collateral values and estimated cash flows related to nonperforming originated loans and purchased credit impaired loans, reductions in nonperforming originated loans and purchased credit impaired loans, and decreases in loss histories for performing originated loans compared to year-ago levels. Also, On October 3, 2014, in accordance with generally accepted accounting principles, the Company recorded the loans acquired in the North Valley Bancorp acquisition at fair value, including the effects of any credit deterioration; and this acquisition method of accounting precludes the need for a separate allowance for loan losses related to the North Valley Bancorp loans on October 3, 2014. In addition, the Company analyzed the North Valley Bancorp loans for impairment and identified $11,488,000 of such loans as impaired, determined their fair value to be $9,411,000, and placed, or kept, them in nonaccrual status as of October 3, 2014.

The following table presents the cost basis, fair value discount, and fair value of loans acquired from North Valley Bancorp on October 3, 2014:

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

Noninterest income increased $2,402,000 (32.7%) to $9,755,000 during the three months ended December 31, 2014 compared to the three months ended December 31, 2013. The increase in noninterest income was due primarily to the North Valley Bancorp acquisition and its related service charges on deposit accounts, interchange revenue, and increase in cash value of life insurance, and the Company’s own improvement in interchange revenue, other noninterest income and change in indemnification asset, that were partially offset by a decrease in change in value of mortgage service rights. The decrease in the change in value of mortgage servicing rights was due primarily to a decrease in estimated prepayment speeds of such mortgages during the three months ended December 31, 2014 versus a smaller decrease in estimated prepayment speeds during the three months ended December 31, 2013. An increase in estimated prepayment speed decreases the value of mortgage servicing rights. Mortgage prepayment speed generally increases when market rates for mortgages decrease, and vice versa. The improvement in change in indemnification asset was primarily due to stable and low expectations of future losses with respect to loans covered by a loss-sharing agreement with the FDIC when compared to changes in the year-ago quarter. The increase in ATM fees and interchange revenue was primarily due to increased interchange revenue from the negotiation of a more favorable agreement with the Company’s interchange service provider, increased sales efforts in this area, and the acquisition of North Valley Bancorp and its customer base.

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

Salaries and benefits expense increased $4,331,000 (32.8%) to $17,555,000 during the three months ended December 31, 2014 compared to the three months ended December 31, 2013. Base salaries increased $3,570,000 (40.4%) to $12,402,000 during the three months ended December 31, 2014 versus the year ago period primarily due to the North Valley Bancorp acquisition. The average number of full time equivalent employees increased 227 (31.1%) to 957 during the three months end December 31, 2014 when compared to the year-ago quarter. The increase in full time equivalent employees is due to the addition of employees from the North Valley Bancorp acquisition and the addition of operations, compliance, marketing, and administrative employees, that were partially offset by reductions of employees from the consolidation of three, two, one and one Tri Counties Bank branches during the three months ended December 31, 2013, and March 31, June 30, and September 30, 2014, respectively. Annual salary merit increases of approximately 3.0% also contributed to the increase in base salary expense. Incentive and commission related salary expenses increased $532,000 (56.4%) to $1,475,000 during three months ended December 31, 2014 due to increases in all types of incentive compensation. Benefits expense, including retirement, medical and workers’ compensation insurance, and taxes, increased $229,000 (6.6%) to $3,678,000 during the three months ended December 31, 2014 due to small to no increases in most benefit types that were partially offset by a $170,000 (32%) decrease in retirement expense when compared to the three months ended December 31, 2013.

Other noninterest expense increased $7,357,000 (63.1%) to $19,011,000 during the three months ended December 31, 2014 compared to the three months ended December 31, 2013. The increase in other noninterest expense was due primarily to a $3,278,000 increase in merger related expense to $3,590,000, of which $438,000 are not deductible for tax purposes, and a $1,105,000 (84.9%) increase in data processing and software expenses to $2,407,000. The increase in merger expenses was due to the North Valley Bancorp acquisition and included stay bonuses, severance pay, and other retention incentives, system conversion and other data processing expenses, professional fees including financial advisor and other consultant fees. The increase in data processing and software expenses was due primarily to increases in ongoing data processing and software expenses some of which are due to increased ongoing processing volume as a result of the North Valley Bancorp acquisition. Increases in other areas of noninterest expense are primarily due to the North Valley Bancorp acquisition.

Richard Smith, President and CEO of Tri Counties Bank commented, “We are pleased to report the conversion of the North Valley Bank data onto the Tri Counties Bank data systems was completed within just three weeks of the acquisition date. This significant achievement furthers our efforts to streamline the business operations of the combined bank. This also provided us the opportunity to streamline our branch network with the closing of eight branches by January 21, 2015. This swift progress was made possible due to the loyal and dedicated team of employees from both North Valley Bank and Tri Counties Bank. “

Smith added, “We are most thankful to all former North Valley Bank customers who placed their trust in us as their primary banking institution and supported our efforts through the conversion. Our retention of customers since the acquisition has exceeded our projections and is further confirmation of our expectation for a successful merger of our companies.”

In addition to the historical information contained herein, this press release may contain forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements are subject to various uncertainties and risks that could affect their outcome. The Company’s actual results could differ materially. 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, the Company’s ability to effectively integrate the business of North Valley Bancorp, 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, 2013. 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. The Company does not intend to update any of the forward-looking statements after the date of this release.

Established in 1975, Tri Counties Bank is a wholly-owned subsidiary of TriCo Bancshares (NASDAQ: TCBK) headquartered in Chico, California, providing a unique brand of customer Service with Solutions available in traditional stand-alone and in-store bank branches in communities throughout Northern and Central California. Tri Counties Bank provides an extensive and competitive breadth of consumer, small business and commercial banking financial services, along with convenient around-the-clock ATM, online and mobile banking access. Brokerage services are provided by the Bank’s investment services through affiliation with Raymond James Financial Services, Inc. Visit www.TriCountiesBank.com to learn more.

TRICO BANCSHARES - CONSOLIDATED FINANCIAL DATA

(Unaudited. Dollars in thousands, except share data)

TRICO BANCSHARES - CONSOLIDATED FINANCIAL DATA

(Unaudited. Dollars in thousands)