Earthstone Energy, Inc. Announces Increase in Borrowing Base

THE WOODLANDS, Texas–(BUSINESS WIRE)–Earthstone Energy, Inc. (NYSE: ESTE) (“Earthstone” or the “Company”),
today announced that the borrowing base under its senior secured
revolving credit facility (“Credit Facility”) has been increased from
$150 million to $185 million in connection with its regularly scheduled
fall redetermination. The Company also entered into an amendment to its
Credit Facility which provides for increased flexibility. The $185
million borrowing base will not be reduced upon closing of the Company’s
previously announced agreement to sell its Bakken assets.

Mark Lumpkin, Jr., Executive Vice President & Chief Financial Officer,
commented, “The increase in the borrowing base of our Credit Facility
reflects the results the Company is achieving through our continuous
drilling program in the Midland Basin. We expect to enter 2018 with low
leverage and strong liquidity, positioning Earthstone to grow our asset
base both through the drill bit and through acquisitions. We appreciate
the continued support of our lenders.”

About Earthstone Energy, Inc.

Earthstone Energy, Inc. is a growth-oriented, independent energy company
engaged in developing and operating oil and gas properties. The
Company’s primary assets are located in the Midland Basin of west Texas
and the Eagle Ford trend of south Texas. Earthstone is listed on NYSE
under the symbol “ESTE.” For more information, visit the Company’s
website at www.earthstoneenergy.com.

Forward-Looking Statements

This 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”). Statements that are not strictly
historical statements constitute forward-looking statements and may
often, but not always, be identified by the use of such words such as
“expects,” “believes,” “intends,” “anticipates,” “plans,” “estimates,”
“potential,” “possible,” or “probable” or statements that certain
actions, events or results “may,” “will,” “should,” or “could” be taken,
occur or be achieved. Forward-looking statements are based on current
expectations and assumptions and analyses made by Earthstone and its
management in light of experience and perception of historical trends,
current conditions and expected future developments, as well as other
factors appropriate under the circumstances that involve various risks
and uncertainties that could cause actual results to differ materially
from those reflected in the statements. These risks include, but are not
limited to, those set forth in Earthstone’s annual report on Form 10-K/A
for the year ended December 31, 2016, quarterly reports on Form 10-Q,
recent current reports on Form 8-K and Form 8-K/A, and other Securities
and Exchange Commission filings. Earthstone undertakes no obligation to
revise or update publicly any forward-looking statements except as
required by law.

Contacts

Earthstone Energy, Inc.
Mark Lumpkin, Jr., 281-298-4246
Executive
Vice President – Chief Financial Officer
mark.lumpkin@earthstoneenergy.com
or
Scott
Thelander, 281-298-4246
Director of Finance
scott@earthstoneenergy.com