Earthstone Energy, Inc. is a growth-oriented, independent energy company engaged in the acquisition, development and operation of oil and natural gas properties. Its primary assets are located in the Midland Basin of west Texas and the Eagle Ford Trend of south Texas. Earthstone is listed on the New York Stock Exchange under the symbol "ESTE." For more information, visit the Company's website at www.earthstoneenergy.com. _____________________ (1) Estimated $42 million of Adjusted EBITDAX is measured from the Bolt-On Acquisition effective date of 7/1/2021 through 6/30/2022 based on Earthstone management estimates of proved developed reserves utilizing NYMEX strip pricing as of 9/30/2021. As used in this news release "Adjusted EBITDAX", a non-GAAP financial measure is defined by Earthstone as net income plus, when applicable, accretion of asset retirement obligations; impairment expense; depletion, depreciation and amortization; interest expense, net; transaction costs; loss (gain) on sale of oil and gas properties; unrealized (gain) loss on derivatives; stock-based compensation; and income tax expense. (2) PV-10 is a non-GAAP measure that differs from a measure under GAAP known as "standardized measure of discounted future net cash flows" in that PV-10 is calculated without including future income taxes. Earthstone management estimate of proved developed producing reserve volumes and values as of 7/1/2021, discounting cash flows at a rate of 10% and utilizing NYMEX strip prices as of 9/30/2021. (3) Earthstone defines leverage as total debt to Adjusted EBITDAX. Target includes Adjusted EBITDAX as adjusted for the impact of 2021 acquisitions.