There are 9 US Post Offices in Davis County serving a total of 300,832 residents equating to 33,426 residents per post office. It's estimated that approximately 480,161 packages are handled across the 9 county post offices annually. Davis County is a county located in the U.S. state of Utah. As of the 2010 census, the population was 306,479, making it the third-most populous county in Utah. Its county seat is Farmington, and its largest city is Layton. The county was created in 1850 and was named for Daniel C. Davis, captain in the Mormon Battalion. Davis County is part of the Ogden-Clearfield, UT Metropolitan Statistical Area as well as the Salt Lake City-Provo-Orem, UT Combined Statistical Area."