Exhibit 99.1

Eclipse Resources Corporation Announces First Quarter 2017 Results: Higher Production, Production Guidance Raised, Operating Expense Guidance Reduced, Increased Utica Shale Dry Gas Type Curve and new 19,300 foot “Super-Lateral” Drilled

STATE COLLEGE, PA- May 4, 2017- (BUSINESS WIRE) - Eclipse Resources Corporation (NYSE:ECR) (the “Company” or “Eclipse Resources”) today announced its first quarter 2017 financial and operational results, along with updated guidance for the second quarter of 2017 and full year 2017. In conjunction with this release, the Company has posted an updated investor presentation to its website at www.eclipseresources.com with additional first quarter results and operational detail.

First Quarter 2017 Highlights:

Subsequent to the end of the First Quarter:

Benjamin W. Hulburt, Chairman, President and CEO, commented on the Company’s first quarter 2017 results, “This was another tremendous quarter for us as we continued our track record of exceeding production expectations, while expanding our operating margin

by keeping our per unit operating expenses and our general & administrative expenses low.  This now marks the tenth consecutive reporting period in which the Company has met or exceeded its production and operating expense guidance, continuing our streak representing every single reporting period since our initial public offering in June of 2014.

We have increased our Utica Dry Gas type curve expectations as a result of the outperformance we have seen to date on our recent Dry Gas type curve area wells. These wells utilized our “Gen3” completion design and managed pressure drawdown methodology. The Utica Dry Gas type curve area EUR has increased to 2.2 Bcfe per 1,000 foot of lateral or by approximately 13%.  The “Gen3” Dry Gas wells we have tested to date are projected to exceed this new type curve EUR, as they are on the eastern side of our Utica Shale Dry Gas acreage, while our Utica Shale Dry Gas type curve is intended to represent the mid-point of expected results rather than the highest possible recovery we believe is possible.  However, as excited as we are with these results, we continue to strive to be a leader in innovation in our region. As such, we have commenced a series of trials on what may become our “Gen4” completion design.  These approaches include testing combinations of tighter stages, higher proppant intensity, engineered stage lengths and the use of diversion chemicals, all of which were tested on a recently completed seven well Dry Gas Utica pad that is expected to begin turning to sales at the end of the second quarter. Because of the need to take several producing wells offline due to offsetting completion activities and the timing of the turn to sales of these new “Gen4” wells at the very end of the second quarter, we expect second quarter production to be down relative to the first and to achieve very strong production growth as we move into the third and fourth quarters.  This was part of our annual plan and as you can see from our updated guidance, we now expect to achieve full year production levels that are in excess of our previously issued guidance.

Our second operated rig commenced drilling at the end of the first quarter 2017 and we now have a rig again focused on our Utica Condensate type curve area as our team continues to demonstrate its operational excellence in the Appalachian basin.  In the Utica Condensate area, I am extremely happy to announce that we successfully drilled what we believe is the world’s longest onshore lateral ever drilled with a total measured depth of 27,400 feet and completable lateral extension of 19,300 feet, almost 1,000 feet longer than the previous record held by our Purple Hayes well.  Remarkably, our team drilled this well in less than 17 days from spud to TD. We are currently drilling a direct offset to this well with a similar planned lateral extension and expect to begin completions on these exciting wells late in the third quarter of this year. Additionally, we have drilled the first of two planned Marcellus Condensate wells with a completable lateral extension of 10,000 feet and are currently drilling the second, along with three Utica Dry Gas wells on the same pad. Considering the catalysts we discussed at our analyst day early in the year, we are tracking at or better than planned and remain excited for continued operational improvement and value enhancements from our assets.”

Operational Discussion

The Company’s production for the three months ended March 31, 2017 and 2016 is set forth in the following table:

Market Conditions

Prices for various quantities of natural gas, NGLs and oil that we produce significantly impact our revenues and cash flows. Prices for commodities, such as hydrocarbons, are inherently volatile. The following table lists average, high, low and average monthly settled NYMEX Henry Hub prices for natural gas and NYMEX WTI prices for oil for the three months ended March 31, 2017 and 2016:

Financial Discussion

Revenue for the first quarter of 2017 totaled $101.9 million, compared to $49.6 million for the first quarter of 2016.  Adjusted Revenue², which includes the impact of cash settled derivatives and excludes brokered natural gas and marketing revenue, totaled $95.4 million for the first quarter of 2017 compared to $58.9 million for the first quarter of 2016.  Net Income for the first quarter of 2017 was $26.8 million, or $0.10 per share compared to a net loss of $45.5 million or $0.20 per share for the first quarter of 2016. Adjusted Net Income² for the first quarter of 2017 was $4.8 million, or $0.02 per share. Adjusted EBITDAX² was $50.2 million for the first quarter of 2017.

Average realized price calculations for the three months ended March 31, 2017 and 2016 are set forth in the table below:

The Company’s operating expenses per Mcfe for the first quarter of 2017 decreased by 6% compared to the prior year’s quarter and are shown in the table below.  Per unit cash production costs (includes lease operating, transportation, gathering and compression, production and ad valorem taxes) were $1.43 per Mcfe for the first quarter 2017 and includes $0.42 per Mcfe of firm transportation expenses.

Capital Expenditures

First quarter 2017 capital expenditures were $78.7 million. These expenditures included $55.0 million for drilling and completions, $2.5 million for midstream expenditures, $21.0 million for land-related expenditures, and $0.2 million for corporate-related expenditures.

During the first quarter 2017, the Company drilled 4 gross (3.9 net) operated Utica Shale wells, all of which were in the Dry Gas type curve area.  In addition, the Company completed 7 gross (7.0 net) wells and turned to sales 5 gross (4.7 net) wells.  

Financial Position and Liquidity

As of March 31, 2017, the Company’s liquidity was $301.9 million, consisting of $160.5 million in cash and cash equivalents and $141.4 million in available borrowing capacity under the Company’s revolving credit facility (after giving effect to outstanding letters of credit issued by the Company of $33.6 million).

As previously announced, the Company completed its borrowing base redetermination of its revolving credit facility, which resulted in an increase in its borrowing base from $125 million to $175 million, and extended the maturity of its revolving credit facility to January 2020. The Company remains undrawn on its revolving credit facility, other than for letters of credit.

Matthew R. DeNezza, Executive Vice President and Chief Financial Officer, commented, “As we continue to increase our activity levels with the addition of the second operated rig, we remain focused on our liquidity and balance sheet strength. At quarter end, our liquidity was approximately $302 million, and included a cash position of approximately $161 million and undrawn revolver availability of approximately $141 million. From a gas marketing perspective, the Company has continued to work to maximize realized pricing through our access to both in and out of basin markets, and we are pleased to see the improvement in Appalachian basis differentials which we had predicted would occur as new transportation capacity is now coming on line.”

Commodity Derivatives

The Company engages in a number of different commodity trading program strategies as a risk management tool to attempt to mitigate the potential negative impact on cash flows caused by price fluctuations in natural gas, NGL and oil prices. Below is a table that illustrates the Company’s hedging activities as of March 31, 2017:

Natural Gas Derivatives

Oil Derivatives

NGL Derivatives

Subsequent to March 31, 2017, the Company entered into the following derivative instruments:

Guidance

The Company issued the following second quarter and full year 2017 guidance in the table below:

₂.         Excludes the cost of firm transportation.

_4.          Non-GAAP measure which excludes non-cash compensation, see reconciliation.

_5.            Excludes potential acquisitions and payments of approximately $17 million for land leased in 2016 and expected to be paid in 2017.

Conference Call

A conference call to review the Company’s financial first quarter 2017 earnings is scheduled for Friday, May 5, 2017, at 10:00 a.m. (Eastern). To participate in the call, please dial 877-709-8150, or 201-689-8354 for international callers, and reference Eclipse Resources First Quarter Earnings Call. A replay of the call will be available through June 5, 2017. To access the phone replay dial 877-660-6853 or 201-612-7415 for international callers. The conference ID is 13660399. A live webcast of the call may be accessed through the “Investors” section of the Company’s website at www.eclipseresources.com.

ECLIPSE RESOURCES CORPORATION

CONDENSED CONSOLIDATED BALANCE SHEETS

(In thousands, except share and per share amounts)

(Unaudited)

ECLIPSE RESOURCES CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(In thousands, except per share data)

(Unaudited)

Adjusted Revenue

Adjusted revenue is a non-GAAP financial measure.  The Company defines Adjusted revenue as follows: total revenues plus net cash receipts or payments settled derivative instruments less brokered natural gas and marketing revenue.  The Company believes Adjusted revenue provides investors with helpful information with respect to the performance of the Company's operations and management uses Adjusted revenue to evaluate its ongoing operations and for internal planning and forecasting purposes. See the table below, which reconciles Adjusted revenue and total revenues.

Adjusted Net Income

Adjusted net income or loss represents income or loss before income taxes adjusted for certain non-cash items as set forth in the table below. We believe Adjusted net income is used by many investors and published research in making investment decisions and evaluating operational trends of the Company and its performance relative to other oil and gas producing companies.  Adjusted net income or loss is not a measure of net income or loss as determined by GAAP.  See the table below for a reconciliation of Adjusted net income or loss and net income or net loss.

Adjusted EBITDAX

Adjusted EBITDAX is a supplemental non-GAAP measure that is used by the Company to evaluate its financial results. The Company defines Adjusted EBITDAX as net income or loss before interest expense; income taxes; impairments; depreciation, depletion and

amortization (“DD&A”); gain (loss) on derivative instruments, net cash receipts (payments on settled derivative instruments, and premiums (paid) received on options that settled during the period); non-cash compensation expense; gain or loss from sale of interest in gas properties; exploration expenses; and other unusual or infrequent items set forth in the table below. Adjusted EBITDAX is not a measure of net income or loss as determined by GAAP.  See the table below for a reconciliation of Adjusted EBITDAX to net income or net loss.

Cash General and Administrative Expenses

Cash General and Administrative Expenses is a non-GAAP financial measure used by the Company in the Guidance Table to provide a measure of Administrative expenses used by many investors and published research in making investment decisions and evaluating operational trends of the Company. See the table below for a reconciliation of Cash General and Administrative Expenses and General and Administrative Expenses.

About Eclipse Resources

Eclipse Resources is an independent exploration and production company engaged in the acquisition and development of oil and natural gas properties in the Appalachian Basin, including the Utica and Marcellus Shales. For more information, please visit the Company’s website at www.eclipseresources.com.

Forward-Looking Statements

This press release contains “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”) and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). All statements, other than statements of historical fact included in this press release, regarding Eclipse Resources’ strategy, future operations, financial position, estimated revenues and income/losses, projected costs and capital expenditures, prospects, plans and objectives of management are forward-looking statements. When used in this press release, the words “plan,” “endeavor,” “will,” “would,” “could,” “believe,” “anticipate,” “intend,” “estimate,” “expect,” “project” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain such identifying words. These forward-looking statements are based on Eclipse Resources’ current expectations and assumptions about future events and are based on currently available information as to the outcome and timing of future events. When considering forward-looking statements, you should keep in mind the risk factors and other cautionary statements described under the heading “Risk Factors” in Eclipse Resources’ Annual Report on Form 10-K filed

with the Securities Exchange Commission on March 3, 2017 (the “2016 Annual Report”), and in “Item 1A. Risk Factors” of Eclipse Resources’ Quarterly Reports on Form 10-Q.

Forward-looking statements may include statements about Eclipse Resources’ business strategy; reserves; general economic conditions; financial strategy, liquidity and capital required for developing its properties and timing related thereto; realized natural gas, NGLs and oil prices; timing and amount of future production of natural gas, NGLs and oil; its hedging strategy and results; future drilling plans; competition and government regulations, including those related to hydraulic fracturing; the anticipated benefits under its commercial agreements; pending legal matters relating to its leases; marketing of natural gas, NGLs and oil; leasehold and business acquisitions; the costs, terms and availability of gathering, processing, fractionation and other midstream services; general economic conditions; credit markets; uncertainty regarding its future operating results, including initial production rates and liquid yields in its type curve areas; and plans, objectives, expectations and intentions contained in this press release that are not historical.

Eclipse Resources cautions you that these forward-looking statements are subject to all of the risks and uncertainties, most of which are difficult to predict and many of which are beyond its control, incident to the exploration for and development, production, gathering and sale of natural gas, NGLs and oil. These risks include, but are not limited to; legal and environmental risks, drilling and other operating risks, regulatory changes, commodity price volatility and the recent significant decline of the price of natural gas, NGLs, and oil, inflation, lack of availability of drilling, production and processing equipment and services, counterparty credit risk, the uncertainty inherent in estimating natural gas, NGLs and oil reserves and in projecting future rates of production, cash flow and access to capital, the timing of development expenditures, and the other risks described under the heading “Risk Factors” in the 2016 Annual Report and in “Item 1A. Risk Factors” of Eclipse Resources’ Quarterly Reports on Form 10-Q.

All forward-looking statements, expressed or implied, included in this press release are expressly qualified in their entirety by this cautionary statement. This cautionary statement should also be considered in connection with any subsequent written or oral forward-looking statements that Eclipse Resources or persons acting on the Company’s behalf may issue.

Contact:

Eclipse Resources Corporation

Douglas Kris, Investor Relations

814-325-2059

dkris@eclipseresources.com