There are 29 counties in Utah. In 2019, Utah's most populous county is Salt Lake County, home to Salt Lake City, with a population of 1,135,649. This represents growth of 9.94% since the 2010 census. Salt Lake County is followed by Utah County (606,425), Davis County (347,637), Weber County (251,769), Washington County (165,662), and Cache County (124,438). These are the only Utah counties with a population of more than 75,000. Of these counties, Washington County has had the most impressive growth rate since the census at 19.70%. All of these counties have grown at a rate of more than 8%, however.
The least populated county in Utah is Daggett County with 1,029 residents. The county's growth rate since the census is -4.46%. Other counties with a population of 5,000 or less include Piute County (1,420), Rich County (2,391), Wayne County (2,719), and Garfield County (5,078). All of these counties have experienced a population decline except Rich County, which has grown by 6.03%.
The Utah county with the most impressive growth rate is Wasatch County, which has grown significantly by 35.79% to 32,106. Many Utah counties have experienced rapid growth, including Morgan County (24.70%), Washington County (19.70%), Utah County (16.63%), Tooele County (15.31%), and Summit County (12.62%). Piute County, with 1,420 residents, has experienced the greatest decline of 9.27% followed by Emergy County (-8.43%).