SM Energy Company is a company engaged in hydrocarbon exploration. It is organized in Delaware and headquartered in Denver, Colorado. The company was known as St. Mary Land & Exploration Company until 2010. The company's assets are in the Eagle Ford Group (57% of reserves and 45% of 2020 production) and the Permian Basin (43% of reserves and 55% of 2020 production). As of December 31, 2020, the company had 404.6 million barrels of oil equivalent (2.475×109 GJ) of estimated proved reserves, of which 40% was petroleum, 16% was natural gas liquids, and 44% was natural gas.