Exhibit 99.1

Civista Bancshares, Inc. Announces Third Quarter 2016 Earnings

Sandusky, Ohio, October 21, 2016 /PRNewswire/– Civista Bancshares, Inc. (NASDAQ:CIVB) (“Civista”) reported net income attributable to common shareholders of $3.3 million, or $0.34 per diluted share, for the third quarter of 2016, compared with $2.9 million, or $0.30 per diluted share, for the prior year period. For the nine-month period ended September 30, 2016, Civista reported net income available to common shareholders of $12.4 million or $1.24 per diluted share, compared to $8.4 million, or $0.87 per diluted share, in the same period of 2015. Civista’s 2016 year-to-date performance includes the second quarter receipt of a payoff on a non-performing loan which resulted in a negative provision of $1.3 million and additional interest income of $918 thousand. These two items approximated $1.5 million after tax, or approximately $0.13 per diluted share. Without this transaction, the diluted earnings per share would have been $1.11 for the nine months ended September 30, 2016.

“September 30, 2016 marked the end to another great quarter for Civista. Diluted earnings per share for the quarter are 13% higher than last year and are in line with the linked quarter when removing one-time items. Our annualized loan growth for the year is 6% and our loan pipeline continues to be strong. Noninterest income has been increasing and we have been successful in keeping noninterest expenses in line.” said James O. Miller, Chairman, President and CEO of Civista.

Results of Operations:

Net interest income for the third quarter of 2016 increased $124 thousand, or 1.0% compared to the same period of 2015 and for the nine months ended September 30 increased $2.5 million, or 7.0%, when compared to the same period of 2015. For the three and nine-month periods ended September 30, an increase in average loans outstanding primarily contributed to the increase in interest income compared to 2015. Tax equivalent net interest margin was 4.06% for the third quarter, compared to 4.13% for the same period a year ago and 3.89% for the nine months ended September 30, 2016, compared to 3.91% for the same period a year ago. Year-to-date net interest margin was reduced in both periods due to the impact of additional interest-earning cash on deposit related to the tax refund processing program. Year-to-date average cash related to the tax refund processing program 2016 and 2015 was $93 million and $49 million, respectively. The reduction to net interest margin due to the additional cash from the tax refund processing program was 26 basis points in 2016 and 15 basis points in 2015.

Summary Average Balance Sheet

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Summary Average Balance Sheet

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No provision for loan losses was made for the third quarter of 2016. For the nine months ended September 30, 2016, the provision was a negative $1.3 million due to ongoing improvement in the loan portfolio and recognition of a $1.3 million recovery due to the resolution of a nonperforming loan relationship that paid off. The provision for the three and nine-month periods ended September 30, 2015 was $400 thousand and $1.2 million, respectively.

During the quarter, noninterest income totaled $3.7 million, an increase of $577 thousand, or 18.8%, compared to the prior year’s third quarter. Year-to-date noninterest income totaled $13.0 million, an increase of $1.9 million, or 16.7%, compared to the prior year’s first nine months.

Noninterest income

Service charge income decreased $68 thousand in the three-month period ended September 30, 2016 compared to 2015, due to reduced overdraft charges. For the nine-month period, service charges increased $227 thousand, primarily due to a new large customer relationship. Gain on sale of loans increased $272 thousand and $453 thousand for the three and nine-month periods ended September 30, respectively. The increase in gain on sale of loans for both periods was due to additional volume of loans sold as well as an increase in the premium on loans sold. Wealth management fees increased $29 thousand for the three-month period, but decreased $170 thousand for the nine-month period. Assets under management have increased $27 million during the year from $397 million at December 31, 2015 to $424 million at September 30, 2016. Average assets under management were $408 million and $429 million for the nine months ended September 31, 2016 and 2015, respectively. Tax refund processing fees increased $750 thousand in the nine-month period due to a higher contract fee to compensate for an increase in the volume of refunds processed.

During the quarter, noninterest expense totaled $11.2 million, an increase of $529 thousand, or 5.0%, compared to the prior year’s third quarter. Year-to-date noninterest expense increased $950 thousand, or 3.0%, when compared to the nine months of 2015.

Noninterest expense

Salaries, wages and benefits expense increased $350 thousand for the third quarter and $1.3 million for the nine-month period ending September 30, 2016. The increases in salaries, wages and benefits expense for both periods were primarily due normal merit increases, increased insurance expense and increased incentive expense. Net occupancy and equipment increased $304 thousand for both the three and nine-month periods ended September 30 2016 due primarily to repair and maintenance and rent expense. Contracted data processing decreased $245 thousand for the nine-month period ended September 30, 2016. Professional services decreased $166 thousand and $266 thousand for the three and nine-month periods ended September 30, 2016. The year-to-date decreases to data processing and professional services were primarily due to expenses related to the acquisition of TCNB Financial Corporation in 2015. Overall acquisition related expenses included in the nine months ended September 30, 2015 approximate $390 thousand.

The year-to-date efficiency ratio was 63.1% during 2016 compared to 66.9% for 2015. The improvement in the efficiency ratio is due to the increase in net interest income, including the $918 thousand recovered interest income, as well as the increase in noninterest income, partially offset by a modest increase in noninterest expense.

Balance Sheet

Total assets increased $57.2 million, or 4.4%, from December 31, 2015 to September 30, 2016, due primarily to loan growth.

Total loans increased $45.4 million or 4.5% from December 31, 2015 to September 30, 2016. The increase in total loans is primarily due to increased Commercial Real Estate – Non-owner Occupied and Residential Real Estate.

End of period loan balances

(dollars in thousands)

Mr. Miller continued, “Our annualized growth in the loan portfolio is 6% for the first nine-months of 2016. In addition, mortgage loans sold increased 32% for the first nine-months of 2016.”

Total deposits increased $82.1 million, or 7.8%, from December 31, 2015 to September 30, 2016, due primarily to increases in public fund deposits, business deposits and brokered deposits. Cash balances remaining related to the tax refund processing program also contributed to the increase.

End of period deposit balances

(dollars in thousands)

Federal Home Loan Bank advances decreased $36.2 million or 50.8% from December 31, 2015 to September 30, 2016, primarily due to the increase in deposits.

Total shareholder’s equity increased $13.1 million, or 10.5%, from December 31, 2015 to September 30, 2016 primarily due to increased retained earnings of $11.2 million and a $1.7 million increase in other comprehensive income, primarily related to unrealized gains in the investment portfolio.

Asset Quality

Nonperforming assets at September 30, 2016 were $13.1 million, a $205 thousand decrease from December 31, 2015. The Company recorded net charge-offs of $1.1 million for the third quarter of 2016 compared to net charge-offs of $347 thousand for the same period of 2015. The increase in net charge-offs is due to two loan relationships that were not previously considered problem loans. Year-to-date, net recoveries were $390 thousand for 2016 compared to net charge-offs of $708 thousand for the same period of 2015.

Non-performing Assets

Civista Bancshares, Inc. is a $1.4 billion financial holding company headquartered in Sandusky, Ohio. The Company’s banking subsidiary, Civista Bank, operates 28 locations in North Central, West Central and Southwestern Ohio.

Civista Bancshares, Inc. may be accessed at www.civb.com. The Company’s common shares are traded on the NASDAQ Capital Market under the symbol “CIVB”. The Company’s depositary shares, each representing a 1/40^th ownership interest in a Series B Preferred Share, are traded on the NASDAQ Capital Market under the symbol “CIVBP”.

This press release may contain forward-looking statements regarding the financial performance, business prospects, growth and operating strategies of Civista. For these statements, Civista claims the protections of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. Statements in this press release should be considered in conjunction with the other information available about Civista, including the information in the filings we make with the Securities and Exchange Commission. Forward-looking statements provide current expectations or forecasts of future events and are not guarantees of future performance. The forward-looking statements are based on management’s expectations and are subject to a number of risks and uncertainties. We have tried, wherever possible, to identify such statements by using words such as “anticipate,” “estimate,” “project,” “intend,” “plan,” “believe,” “will” and similar expressions in connection with any discussion of future operating or financial performance. Although management believes that the expectations reflected in such forward-looking statements are reasonable, actual results may differ materially from those expressed or implied in such statements. Risks and uncertainties that could cause actual results to differ materially include risk factors relating to the banking industry and the other factors detailed from time to time in Civista’ reports filed with the Securities and Exchange Commission, including those described in “Item 1A Risk Factors” of Part I of Civista’s Annual Report on Form 10-K for the fiscal year ended December 31, 2015. Undue reliance should not be placed on the forward-looking statements, which speak only as of the date hereof. Civista does not undertake, and specifically disclaims any obligation, to publicly release the result of any revisions that may be made to update any forward-looking statement to reflect the events or circumstances after the date on which the forward-looking statement is made, or reflect the occurrence of unanticipated events, except to the extent required by law.

For additional information, contact:

James O. Miller

Chairman, President and CEO

Civista Bancshares, Inc.

888-645-4121

Civista Bancshares, Inc.

Financial Highlights

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Consolidated Condensed Statement of Income

Selected Balance Sheet Items

Average Balance Analysis

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* - All yields and costs are presented on an annualized basis

Average Balance Analysis

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Supplemental Financial Information

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Supplemental Financial Information

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