Exhibit 99.1

ESSA BANCORP, INC. ANNOUNCES FISCAL THIRD QUARTER FINANCIAL RESULTS

Stroudsburg, Pennsylvania, July 29, 2015 — ESSA Bancorp, Inc. (the “Company”) (NASDAQ Global Market^SM: ESSA) today reported net income of $2.5 million, or $0.23 per diluted share, for the quarter ended June 30, 2015, compared with net income of $2.6 million, or $0.24 per diluted share, for the same quarter, last year. Net income for the first nine months of fiscal 2015 increased to $7.5 million, or $0.71 per diluted share, compared with net income of $6.1 million, or $0.56 per diluted share, for the nine months of fiscal 2014. Year-over-year comparisons reflect the acquisition of Franklin Security Bancorp in April 2014.

The Company is the holding company for ESSA Bank & Trust, a $1.6 billion asset institution, which provides full service retail and commercial banking, financial, and investment services from 26 locations in eastern Pennsylvania.

THIRD QUARTER HIGHLIGHTS

Gary S. Olson, President and CEO, commented: “Our third quarter results reflect our ability to deliver consistent results despite the earnings challenges presented by continued low interest rates. As we expand into faster-growing markets, we remain focused on loan growth, asset quality, and controlled operating expenses while our efforts to build commercial relationships continue to gain traction.”

Corporate Center: 200 Palmer Street PO Box L Stroudsburg, PA 18360-0160 570-421-0531 Fax: 570-421-7158

As noted when our merger with Eagle National Bancorp was first announced, “We are excited to have this opportunity to expand our market share and establish a commercial presence in an attractive suburban Philadelphia market.”

Income Statement Review

Net interest income decreased $86,000, or 0.8%, to $11.0 million for the three months ended June 30, 2015, from $11.1 million for the comparable period in 2014. Net interest income increased $3.5 million, or 12.0%, to $33.1 million for the nine months ended June 30, 2015, from $29.5 million for the comparable period in 2014, reflecting increases in the Company’s loan portfolio.

Interest expense decreased $171,000 for the nine months ended June 30, 2015 compared to the comparable period in 2014, while interest income increased $3.4 million on growing loan volume. Increases in interest income from indirect auto loans, commercial loans and investment securities helped offset a decrease in interest income from mortgage loans.

The Company’s net interest rate spread was 2.90% for the three months ended June 30, 2015, down from 3.02% for the comparable 2014 period. The Company’s net interest rate spread rose to 2.93% for the nine months ended June 30, 2015 compared to 2.91% for the nine months ended June 30, 2014. Net interest margin was unchanged at 2.99% for the nine months ended June 30, 2015 and 2014.

The Company’s provision for loan losses increased to $525,000 for the three months ended June 30, 2015, compared with $500,000 for the three months ended June 30, 2014. The Company’s provision for loan losses decreased to $1.5 million for the nine months ended June 30, 2015, compared with $2.0 million for the nine months ended June 30, 2014. Net loan charge-offs in fiscal third quarter 2015 were $425,000 compared to $326,000 in fiscal third quarter 2014. Net loan charge-offs for the nine months ended June 30, 2015 were $1.4 million compared to $1.2 million in the 2014 period.

Noninterest income decreased 7.2% to $1.9 million for the three months ended June 30, 2015, compared with $2.1 million for the three months ended June 30, 2014 due principally to declines in trust and investment fees, gain on acquisition, and other income which were partially offset by an increase in gain on sale of investments, net. Noninterest income increased 3.4% to $5.7 million for the nine months ended June 30, 2015, compared with the nine months ended June 30, 2014. The increase was due primarily to increases in service fees and charges related to loans and gain on sale of investments offset in part by a decline in gain on acquisition.

Noninterest expense was $9.4 million for the three months ended June 30, 2015 compared with $9.1 million for the comparable period in 2014. Noninterest expense was $27.4 million for the nine months ended June 30, 2015 compared with $24.7 million for the comparable period in 2014. Increases in expenses primarily reflect additional facilities and costs related to the Franklin Security Bank acquisition.

Balance Sheet, Asset Quality and Capital Adequacy

Total assets were $1.60 billion at June 30, 2015 compared with $1.57 billion at September 30, 2014. Total loans receivable, net of allowance for loan losses, were $1.09 billion at June 30, 2015 compared to $1.06 billion at September 30, 2014.

Total deposits decreased $58.3 million, or 5.1%, to $1.08 billion at June 30, 2015, from $1.13 billion at September 30, 2014. Decreases in interest bearing demand deposits, money market and certificate of deposit accounts were partially offset by increases in non-interest bearing demand and savings and club accounts. During the same period, borrowings increased $70.3 million, reflecting the Company’s ability to obtain borrowed funds at what management believes represent attractive rates.

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Nonperforming assets totaled $23.4 million, or 1.46%, of total assets at June 30, 2015, compared with $25.0 million, or 1.59%, of total assets at September 30, 2014, and $26.2 million, or 1.68% of total assets a year earlier. The decrease in nonperforming assets of $1.6 million at June 30, 2015 compared to September 30, 2014 was due primarily to decreases in non-performing commercial mortgages and foreclosed real estate.

The Company’s provision for loan losses was $525,000 for the three-month period ended June 30, 2015, compared with a provision of $500,000 for the comparable period in 2014, primarily reflecting continued disciplined credit and underwriting standards. The allowance for loan losses was $8.8 million, or 0.80%, of loans outstanding at June 30, 2015, compared to $8.6 million, or 0.81%, of loans outstanding at September 30, 2014.

The Bank continued to demonstrate financial strength, with a tier 1 leverage ratio of 10.02%, exceeding accepted regulatory standards for a well-capitalized institution. The Company maintained a tangible equity to total assets ratio of 9.85%.

Stockholders’ equity increased $4.0 million to $171.3 million at June 30, 2015, from $167.3 million at September 30, 2014. During the three months ended June 30, 2015, the Company repurchased 36,900 shares at an average cost of $12.85 per share. Tangible book value per share at June 30, 2015 increased to $13.94 compared with $13.34 at September 30, 2014.

For the fiscal third quarter of 2015, the Company’s return on average assets and return on average equity were 0.62% and 5.67%, compared with 0.68% and 6.17%,respectively, in the corresponding period of fiscal 2014.

ESSA Bank & Trust, a wholly-owned subsidiary of ESSA Bancorp, Inc., has total assets of $1.60 billion and is the leading service-oriented financial institution headquartered in Stroudsburg, Pennsylvania. ESSA Bank & Trust maintains its corporate headquarters in Stroudsburg, Pennsylvania and has 26 community offices throughout the Greater Pocono, Lehigh Valley, and Scranton/Wilkes-Barre areas in Pennsylvania. In addition to being one of the region’s largest mortgage lenders, ESSA Bank & Trust offers a full range of consumer and commercial banking products and services, employee benefit solutions, Trust & Asset management, and brokerage services. ESSA Bancorp, Inc. stock trades on The NASDAQ Global Select Market (SM) under the symbol “ESSA”.

Forward-Looking Statements

Certain statements contained herein are “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Such forward-looking statements may be identified by reference to a future period or periods, or by the use of forward-looking terminology, such as “may,” “will,” “believe,” “expect,” “estimate,” “anticipate,” “continue,” or similar terms or variations on those terms, or the negative of those terms. Forward-looking statements are subject to numerous risks and uncertainties, including, but not limited to, those related to the economic environment, particularly in the market areas in which the Company operates, competitive products and pricing, fiscal and monetary policies of the U.S. Government, changes in government regulations affecting financial institutions, including compliance costs and capital requirements, changes in prevailing interest rates, acquisitions and the integration of acquired businesses, credit risk management, asset-liability management, the financial and securities markets and the availability of and costs associated with sources of liquidity, and the Risk Factors disclosed in our annual and quarterly reports.

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The Company wishes to caution readers not to place undue reliance on any such forward-looking statements, which speak only as of the date made. The Company wishes to advise readers that the factors listed above could affect the Company’s financial performance and could cause the Company’s actual results for future periods to differ materially from any opinions or statements expressed with respect to future periods in any current statements. The Company does not undertake and specifically declines any obligation to publicly release the result of any revisions, that may be made to any forward-looking statements to reflect events or circumstances after the date of such statements or to reflect the occurrence of anticipated or unanticipated events.

FINANCIAL TABLES FOLLOW

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ESSA BANCORP, INC. AND SUBSIDIARY

CONSOLIDATED BALANCE SHEET

(UNAUDITED)

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ESSA BANCORP, INC. AND SUBSIDIARY

CONSOLIDATED STATEMENT OF INCOME

(UNAUDITED)

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