Boise is the capital and most populous city in the U.S. state of Idaho. It serves as the county seat of Ada County and had a population of 235,685 according to the 2020 census.
The Boise metropolitan area is situated in the Treasure Valley and encompasses five counties in Idaho. With an estimated population of 846,000, it is the most populous metropolitan area in the state and ranks as the 95th-most populous metropolitan area in the United States.