Juab County is a county in western Utah, United States. As of the 2020 United States Census, the population was 11,786. Its county seat and largest city is Nephi.

Nephi is a city in Juab County, Utah, United States. It is part of the Provo–Orem metropolitan area. The population was 6,443 at the 2020 census. It is the county seat of Juab County. It was settled by Mormon pioneers in 1851 as Salt Creek, and it acquired its current name in 1882. It is the principal city in the Juab Valley, an agricultural area. Nephi was named after Nephi, son of Lehi, from the Book of Mormon.