Utah County is the second-most populous county in the U.S. state of Utah. The county seat and largest city is Provo, which is the state's fourth-largest city, and the largest outside of Salt Lake County. As of the 2020 United States Census, the population was 665,665. Utah County is one of two counties forming the Provo–Orem metropolitan statistical area, and is part of the larger Salt Lake City–Provo–Orem, UT Combined Statistical Area.