Exhibit 99.1

News Release

CNB FINANCIAL CORPORATION REPORTS SECOND QUARTER EARNINGS FOR 2015

Clearfield, Pennsylvania – July 20, 2015

CNB Financial Corporation (“CNB”) (NASDAQ: CCNE), the parent company of CNB Bank, today announced its earnings for the second quarter of 2015. Highlights include the following:

Joseph B. Bower, Jr., President and CEO commented, “We were very pleased with the exceptional loan growth in the second quarter. The fact that this growth was spread over our entire market area provides CNB with momentum across our markets. This positive growth helps offset the continued pressure on the net interest margin that is being experienced throughout the banking industry.”

Net Interest Margin

Net interest margin on a fully tax equivalent basis was 3.71% for the six months ended June 30, 2015, compared to 3.79% for the six months ended June 30, 2014. Net accretion included in loan interest income in the first six months of 2015 related to acquired loans was $1.3 million, resulting in an increase in the net interest margin of 13 basis points. Net accretion included in loan interest income in the first six months of 2014 related to acquired loans was $1.2 million, resulting in an increase in the net interest margin of 12 basis points. During the first six months of 2015, CNB experienced net interest margin compression as a result of loans repricing and new loans with market yields significantly below historical averages, which is consistent with the trends across the financial services industry in this historically low interest rate environment. The cost of interest-bearing deposits was 53 basis points during the six months ended June 30, 2015, compared to 52 basis points during the six months ended June 30, 2014.

Asset Quality

During the three and six months ended June 30, 2015, CNB recorded a provision for loan losses of $486 thousand and $1.4 million, as compared to a provision for loan losses of $1.5 million and $2.5 million for the three and six months ended June 30, 2014. Net chargeoffs during the three and six months ended June 30, 2015 were $676 thousand and $1.3 million, as compared to $760 thousand and $1.3 million for the three and six months ended June 30, 2014. There were no new impaired loans in the second quarter of 2015 that required significant specific loan loss reserves, and none of the existing impaired loans required significant additional reserves.

Non-Interest Income

Non-interest income was $4.1 million and $7.2 million for the three and six months ended June 30, 2015, compared to $3.5 million and $6.7 million for the three and six months ended June 30, 2014. Non-interest income as a percentage of average assets increased from 0.63% during the first six months of 2014 to 0.66% during the first six months of 2015, in part due to an increase in net realized and unrealized securities gains of $152 thousand.

Non-Interest Expenses

Total non-interest expenses were $14.1 million and $27.2 million during the three and six months ended June 30, 2015, compared to $12.6 million and $25.9 million for the three and six months ended June 30, 2014. The ratio of non-interest expenses to average assets was 2.47% and 2.42% during the six months ended June 30, 2015 and 2014, respectively. Salaries and benefits expenses increased $860 thousand, or 6.5%, during the six months ended June 30, 2015 compared to the six months ended June 30, 2014. During the first

six months of 2015, CNB hired 20 additional full-time equivalent staff to facilitate the company’s continued growth. In addition, expenses associated with outsourced services increased $173 thousand during the six months ended June 30, 2015 compared to the six months ended June 30, 2014.

About CNB Financial Corporation

CNB Financial Corporation is a financial holding company with consolidated assets of approximately $2.3 billion that conducts business primarily through CNB Bank, CNB’s principal subsidiary. CNB Bank is a full-service bank engaging in a full range of banking activities and services, including trust and wealth management services, for individual, business, governmental, and institutional customers. CNB Bank operations include a private banking division, loan production offices in Hollidaysburg, Pennsylvania and Ashtabula, Ohio, and 29 full-service offices in Pennsylvania, including ERIEBANK, a division of CNB Bank, as well as 9 full-service offices in central Ohio conducting business as FCBank, a division of CNB Bank. More information about CNB and CNB Bank may be found on the internet at www.bankcnb.com.

Forward-Looking Statements

This press release includes forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, with respect to CNB’s financial condition, liquidity, results of operations, future performance and business. These forward-looking statements are intended to be covered by the safe harbor for “forward-looking statements” provided by the Private Securities Litigation Reform Act of 1995. Forward-looking statements are those that are not historical facts. Forward-looking statements include statements with respect to beliefs, plans, objectives, goals, expectations, anticipations, estimates and intentions that are subject to significant risks and uncertainties and are subject to change based on various factors (some of which are beyond CNB’s control). Forward-looking statements often include the words “believes,” “expects,” “anticipates,” “estimates,” “forecasts,” “intends,” “plans,” “targets,” “potentially,” “probably,” “projects,” “outlook” or similar expressions or future conditional verbs such as “may,” “will,” “should,” “would” and “could.” CNB’s actual results may differ materially from those contemplated by the forward-looking statements, which are neither statements of historical fact nor guarantees or assurances of future performance. For more information about factors that could cause actual results to differ from those discussed in the forward-looking statements, please refer to the “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” sections of and the forward-looking statement disclaimers in CNB’s annual and quarterly reports.

The forward-looking statements are based upon management’s beliefs and assumptions and are made as of the date of this press release. CNB undertakes no obligation to publicly update or revise any forward-looking statements included in this press release or to update the reasons why actual results could differ from those contained in such statements, whether as a result of new information, future events or otherwise, except to the extent required by law. In light of these risks, uncertainties and assumptions, the forward-looking events discussed in this press release might not occur and you should not put undue reliance on any forward-looking statements.

Financial Tables

The following tables supplement the financial highlights described previously for CNB Financial Corporation.