Exhibit 99.1

FIRST FINANCIAL BANKSHARES ANNOUNCES FIRST QUARTER EARNINGS RESULTS

ABILENE, Texas, April 21, 2016 – First Financial Bankshares, Inc. (NASDAQ: FFIN) today reported earnings for the first quarter of 2016 of $25.70 million, up 7.08 percent compared with earnings of $24.00 million in the same quarter last year. Basic earnings per share were $0.39 for the first quarter of 2016 compared with $0.37 in the same quarter a year ago.

All amounts for the first quarter ended March 31, 2016, include the results of the asset purchase of 4Trust Mortgage, Inc. on May 31, 2015, and the acquisition of First Bank, N.A., Conroe, Texas, on July 31, 2015. As of the acquisition date, First Bank had total gross loans of $252.46 million and total deposits of $356.75 million.

Net interest income for the first quarter of 2016 increased 11.59 percent to $57.02 million compared with $51.10 million in the same quarter of 2015. The net interest margin, on a taxable equivalent basis, was 4.15 percent for the first quarter of 2016 compared to 4.16 percent in the fourth quarter of 2015 and 4.11 percent in the first quarter of 2015. Included in interest income for the first quarter of 2016 was $720 thousand, or four basis points in net interest margin, related to discount accretion from fair value accounting related to the Conroe and Orange acquisitions.

The provision for loan losses was $2.33 million in the first quarter of 2016 compared with $4.18 million in the fourth quarter of 2015 and $1.29 million in the first quarter of 2015. The continued provision for loan losses in 2016 and 2015 reflects the continued levels of nonperforming and classified assets, gross charge-offs, as well as the economic effects related to the oil and gas industry. Nonperforming assets as a percentage of loans and foreclosed assets totaled 0.88 percent at March 31, 2016, compared with 0.89 percent at December 31, 2015, and 0.69 percent at March 31, 2015. Classified loans totaled $142.14 million at March 31, 2016, compared to $149.43 million at December 31, 2015, and $77.75 million at March 31, 2015. Included in recoveries for the quarter ended March 31, 2016, was a $1.2 million recovery of a previously charge-off commercial real estate loan.

At March 31, 2016, loans with oil and gas industry exposure totaled 2.79% of gross loans. These loans comprised $36.40 million of the classified loan totals and $4.92 million of the nonperforming loan totals. In addition, $517 thousand in net charge-offs was related to these oil and gas loans for the quarter ended March 31, 2016. At March 31, 2016, the Company’s allowance for loan loss reserve specific to its total oil and gas loan portfolio totaled 7.37% of total oil and gas loans.

Noninterest income increased 24.68 percent in the first quarter of 2016 to $19.82 million compared with $15.90 million in the same quarter a year ago. Trust fees decreased $76 thousand to $4.66 million in the first quarter of 2016 compared with $4.73 million in the same quarter last year due to a $257 thousand decline in Trust oil and gas fee income when compared to the same quarter a year ago. This decline was mostly offset by an increase in the fair value of Trust assets managed to $4.01 billion from $3.85 billion a year ago. Service charges on deposits and ATM, interchange and credit card fees increased 17.12 and 14.31 percent, respectively, to $4.41 million and $5.68 million compared with $3.77 million and $4.97 million, respectively, in the same quarter last year due to the acquisition of First Bank and the continued

growth in net new accounts and debit cards. Real estate mortgage fees increased 111.81 percent in the first quarter of 2016 to $3.14 million compared with $1.48 million in the same quarter a year ago, primarily resulting from additional loan origination production from the 4Trust Mortgage, Inc. asset purchase.

Noninterest expense for the first quarter of 2016 totaled $41.08 million compared to $33.94 million in the first quarter of 2015. The Company’s efficiency ratio in the first quarter of 2016 was 49.52 percent compared with 47.01 percent in the same quarter last year. The increase in noninterest expense in the first quarter of 2016 was primarily a result of an increase in salary and employee benefit costs driven by the addition of 4Trust Mortgage Inc. and First Bank employees and annual pay increases.

As of March 31, 2016, consolidated assets for the Company totaled $6.53 billion compared to $6.67 billion at December 31, 2015 and $6.03 billion at March 31, 2015. Loans totaled $3.30 billion at quarter end compared with loans of $3.35 billion at December 31, 2015 and $2.94 billion at March 31, 2015. Deposits totaled $5.06 billion at March 31, 2016, compared to $5.19 billion at December 31, 2015 and $4.84 billion at March 31, 2015. The decline in deposits from December 31, 2015 to March 31, 2016 was primarily due to an unusually large increase in correspondent bank balances at December 31, 2015. Shareholders’ equity rose to $838.61 million as of March 31, 2016, compared with $804.99 million at December 31, 2015 and $706.25 million at March 31, 2015.

“We are pleased to report another successful quarter for the Company, especially with continued low interest rates and depressed oil and gas prices,” said F. Scott Dueser, Chairman, President and CEO. “Going forward, we will remain diligent in our search for opportunities to maximize our efficiencies while we continue to seek additional acquisition opportunities for our company that will fit our culture and bring additional earnings and increase shareholder value.”

About First Financial Bankshares

Headquartered in Abilene, Texas, First Financial Bankshares is a financial holding company that through its subsidiary, First Financial Bank, N.A., operates multiple banking regions with 69 locations in Texas including Abilene, Acton, Albany, Aledo, Alvarado, Beaumont, Boyd, Bridgeport, Brock, Burleson, Cisco, Cleburne, Clyde, Conroe, Cut and Shoot, Decatur, Eastland, Fort Worth, Glen Rose, Granbury, Grapevine, Hereford, Huntsville, Keller, Magnolia, Mauriceville, Merkel, Midlothian, Mineral Wells, Montgomery, Moran, New Waverly, Newton, Odessa, Orange, Port Arthur, Ranger, Rising Star, Roby, San Angelo, Southlake, Stephenville, Sweetwater, Tomball, Trent, Trophy Club, Vidor, Waxahachie, Weatherford, Willis, and Willow Park. The Company also operates First Financial Trust & Asset Management Company, N.A., with nine 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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