Jerome is a city in and the county seat of Jerome County, Idaho, United States. As of the 2020 census, Jerome had a population of 12,349. The city is the county seat of Jerome County, and is part of the Twin Falls Metropolitan Statistical Area. It is the second largest city in Idaho's Magic Valley region, second only to Twin Falls which is located 10 miles (16 km) southeast. Jerome's economy is largely agrarian, with dairy farming being one of the main revenue sources for the local economy.