Exhibit 99.1

FIRST FINANCIAL BANKSHARES ANNOUNCES

FIRST QUARTER EARNINGS RESULTS

ABILENE, Texas, April 18, 2013 – First Financial Bankshares, Inc. (NASDAQ: FFIN) today reported earnings for the first quarter of 2013 of $18.58 million, up 4.62 percent compared with earnings of $17.76 million in the same quarter last year. Basic earnings per share were $0.59 for the first quarter of 2013 compared with $0.56 in the same quarter a year ago.

Net interest income increased 1.08 percent to $38.67 million compared with $38.26 million in the same period of 2012. The net interest margin, on a taxable equivalent basis, was 4.19 percent, up two basis points from 4.17 percent in the fourth quarter of 2012. The net interest margin was 4.39 in the first quarter of 2012.

The provision for loan losses was $401 thousand in the first quarter of 2013, compared with $1.30 million in the same quarter last year and $642 thousand in the fourth quarter of 2012. Nonperforming assets as a percentage of loans and foreclosed assets totaled 1.20 percent at March 31, 2013, compared with 1.22 percent at December 31, 2012, and 1.60 percent at March 31, 2012. Classified loans totaled $70.18 million at March 31, 2013, compared to $67.14 million at December 31, 2012, and $90.36 million at March 31, 2012.

Noninterest income increased 4.98 percent in the first quarter of 2013 to $13.96 million compared with $13.30 million in the same quarter a year ago. Trust fees increased to $3.79 million in the first quarter of 2013 compared with $3.45 million in the same quarter last year primarily due to continued growth in the fair value of Trust assets managed to $3.02 billion from $2.63 billion a year ago. Real estate mortgage fees increased 31.81 percent to $1.38 million compared with $1.05 million in the same quarter last year due to a stronger housing market and increased market share.

Noninterest expense increased in the first quarter of 2013 to $27.47 million from $26.47 million in the same quarter last year. The Company’s efficiency ratio in the first quarter of 2013 was 48.68 percent compared with 48.08 percent in the same quarter last year. Included in noninterest expense for the first quarter of 2013 was $143 thousand, primarily legal and travel, related to the Company’s recently announced acquisition of Orange Savings Bank, SSB, which is expected to close in the second quarter of 2013.

As of March 31, 2013, consolidated assets for the Company totaled $4.46 billion compared with $4.23 billion a year ago. Loans grew 18.86 percent and totaled $2.14 billion at quarter end compared to $1.80 billion a year ago. Total deposits were $3.55 billion as of March 31, 2013, which represents a 4.47 percent growth over $3.40 billion a year earlier. Shareholders’ equity rose to $564.25 million as of March 31, 2013, compared with $517.01 million at March 31, 2012.

“We are pleased to report another profitable quarter for our company,” said F. Scott Dueser, Chairman, President and CEO. “We continue to see good growth in earnings and loans while continuing to work to improve our efficiencies and are excited about our upcoming acquisition of Orange Savings Bank.”

About First Financial Bankshares

Headquartered in Abilene, Texas, First Financial Bankshares is a financial holding company that operates 11 banking regions with 56 locations in Texas including Abilene, Acton, Albany, Aledo, Alvarado, Boyd, Bridgeport, Brock, Burleson, Cisco, Cleburne, Clyde, Crowley, Decatur, Eastland, Fort Worth, Glen Rose, Granbury, Grapevine, Hereford, Huntsville, Keller, Merkel, Midlothian, Mineral Wells, Moran, Odessa, Ranger, Rising Star, Roby, San Angelo, Southlake, Stephenville, Sweetwater, Trent, Trophy Club, Waxahachie, Weatherford and Willow Park. The Company also operates First Financial Trust & Asset Management Company, N.A., with six locations and First Technology Services, Inc., a technology operating company.

The Company is listed on The NASDAQ Global Select Market under the trading symbol FFIN. For more information about First Financial Bankshares, please visit our website at http://www.ffin.com.

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Certain statements contained herein may be considered “forward-looking statements” as defined in the Private Securities Litigation Reform Act of 1995. These statements are based upon the belief of the Company’s management, as well as assumptions made beyond information currently available to the Company’s management, and may be, but not necessarily are, identified by such words as “expect”, “plan”, “anticipate”, “target”, “forecast” and “goal”. Because such “forward-looking statements” are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Factors that could cause actual results to differ materially from the Company’s expectations include competition from other financial institutions and financial holding companies; the effects of and changes in trade, monetary and fiscal policies and laws, including interest rate policies of the Federal Reserve Board; changes in the demand for loans; fluctuations in value of collateral and loan reserves; inflation, interest rate, market and monetary fluctuations; changes in consumer spending, borrowing and savings habits; and acquisitions and integration of acquired businesses, and similar variables. Other key risks are described in the Company’s reports filed with the Securities and Exchange Commission, which may be obtained under “Investor Relations-Documents/Filings” on the Company’s Web site or by writing or calling the Company at 325.627.7155. Except as otherwise stated in this news announcement, the Company does not undertake any obligation to update publicly or revise any forward-looking statements because of new information, future events or otherwise.

FIRST FINANCIAL BANKSHARES, INC.

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FIRST FINANCIAL BANKSHARES, INC.

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