The Seattle metropolitan area is an urban conglomeration in the U.S. state of Washington that comprises Seattle, its surrounding satellites and suburbs. It contains the three most populous counties in the state—King, Snohomish, and Pierce—and is considered part of the greater Puget Sound region. The United States Census Bureau defines the metropolitan area as the Seattle–Tacoma–Bellevue, WA metropolitan statistical area. With an estimated population of 3,979,845 as of 2019, it is the 15th largest metropolitan statistical area (MSA) in the United States and is home to over half of Washington's population.