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, Pierce, and Snohomish counties, 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 4,102,400 , it is the 15th-largest metropolitan statistical area (MSA) in the United States and home to over half of Washington's population. As defined by the U.S. Census Bureau, the Seattle metropolitan area includes: Seattle–Bellevue–Everett metropolitan division King County: Seattle and its immediate vicinity Snohomish County: north of Seattle Tacoma metropolitan division Pierce County: south of Seattle Based on commuting patterns, the adjacent metropolitan areas of Olympia, Bremerton, and Mount Vernon, along with a few smaller satellite urban areas, are grouped together in a wider labor market region known as the Seattle–Tacoma Combined Statistical Area (CSA) (See Figure STO), commonly known as the Puget Sound region. The population of this wider region is 4,686,536—roughly two-thirds of Washington's population—. The Seattle CSA is the 14th largest CSA, and the 13th largest primary census statistical area in the country. The additional metropolitan and micropolitan areas included are: Bremerton–Silverdale metropolitan area Kitsap County: west of Seattle, separated from the city by Puget Sound; connected to Seattle by ferry and to Tacoma by the Tacoma Narrows Bridge Olympia metropolitan area Thurston County: southwest of Seattle, at the south end of Puget Sound Mount Vernon–Anacortes metropolitan area Skagit County Oak Harbor micropolitan area Island County: northwest of Everett, encompassing Whidbey and Camano Islands in Puget Sound Shelton micropolitan area Mason County: west of Tacoma and northwest of Olympia As of the 2020 census there were 4,018,762 people in the area.