636 Area Code belongs to the Missouri (MO) State.
Other cities in the 636 Area Code.
Arnold, Ballwin, Barnhart, Chesterfield, De Soto, Eureka, Festus, Lake St. Louis, O'Fallon, St. Charles, St. Peters, Troy, Union, Washington, Wentzville, Wildwood
Missouri (MO)
also shares with these area codes: