Bellingham is the largest city in and the county seat of Whatcom County in the U.S. state of Washington. It is the thirteenth-largest city in the state, with 85,146 residents in 2015 as estimated by the US Census, or sixth-largest by metropolitan area after Seattle-Tacoma, Spokane, the northern side of the Portland metropolitan area, the Tri-Cities, and Yakima. The boundaries of the city encompass the former towns of Fairhaven, Whatcom, Sehome, and Bellingham.