Southwestern Energy Company is an energy company. It explores for and produces natural gas, oil, and natural gas liquids (NGLs) in the U.S. The company develops unconventional natural gas and oil reservoirs in Pennsylvania, West Virginia, Ohio, and Louisiana. Assets include 1,527 producing wells on 768,050 net acres in Appalachia and proved reserves of 21,148 billion cubic feet of natural gas equivalent. Southwestern Energy was incorporated in 1929 and is headquartered in Spring, TX.