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Earthstone Energy, Inc. (NYSE MKT: ESTE) (“Earthstone”), today announced that, as a result of its lenders’ semiannual review, the borrowing base under its revolving credit facility has been reaffirmed at $80.0 million. Utilization currently includes $11.2 million of indebtedness and $0.3 million of letters of credit. The facility matures on December 19, 2018.

Frank A. Lodzinski, President and Chief Executive Officer of Earthstone Energy, Inc., commented, “We appreciate the continued support of our lenders and their recognition of our quality asset base. Our clean balance sheet and strong liquidity position will enable us to continue our growth throughout 2015.”

About Earthstone Energy, Inc.

Earthstone Energy, Inc. is a growth-oriented independent oil and gas exploration and production company engaged in the development and acquisition of oil and gas reserves through an active and diversified program that includes the acquisition, drilling and development of undeveloped leases, and purchases of reserves and exploration activities, with its current primary assets located in the Eagle Ford trend of south Texas and in the Williston Basin of North Dakota and Montana. Earthstone is traded on NYSE MKT under the symbol “ESTE.” Information on Earthstone can be found atwww.earthstoneenergy.com. Our corporate headquarters is located in The Woodlands, Texas. We also have an operating office in Denver, Colorado.