Nephi is a city in and the county seat of Juab County, Utah, United States. It is part of the Provo–Orem metropolitan area. The population was 6,443 at the 2020 census. It was settled by George Washington Bradley and other Mormon pioneers. George Washington Bradley was also commander of the military post at Nephi, Utah, during the Walker War of 1854. Nephi is the principal city in the Juab Valley, an agricultural area. Nephi was named after Nephi, son of Lehi, from the Book of Mormon.