Franklin County is a county in the U.S. state of Tennessee. It is located on the eastern boundary of Middle Tennessee in the southern part of the state. As of the 2020 census, the population was 42,774. Its county seat is Winchester. Franklin County was formerly part of the Tullahoma-Manchester, TN Micropolitan Statistical Area, it was removed in 202…Franklin County is a county in the U.S. state of Tennessee. It is located on the eastern boundary of Middle Tennessee in the southern part of the state. As of the 2020 census, the population was 42,774. Its county seat is Winchester. Franklin County was formerly part of the Tullahoma-Manchester, TN Micropolitan Statistical Area, it was removed in 2023 and is part of the Winchester Micropolitan Statistical Area.