Jefferson County is an exurban county located in the U.S. state of Tennessee. As of the 2020 census, the population was 54,683. Its county seat is Dandridge. Jefferson County is part of the Morristown Metropolitan Statistical Area with neighboring Grainger and Hamblen counties. The county, along with the Morristown MSA, is included in the Knoxville-Morristown-Sevierville Combined Statistical Area.

Dandridge is a town in and the county seat of Jefferson County, Tennessee. It had a population of 3,344 at the 2020 census. The town is part of the Morristown, Tennessee Metropolitan Statistical Area, which consists of Jefferson, Hamblen, and Grainger counties.