Tennessee Ridge is located at 36°19′15″N 87°45′47″W / 36.32083°N 87.76306°W / 36.32083; -87.76306 (36.320797, -87.763012),[6] at an elevation of 742 feet above sea level.

According to the United States Census Bureau, the town has a total area of 3.7 square miles (9.6 km2), of which 3.7 square miles (9.6 km2) is land and 0.27% is water.

As of the 2020 United States census, there were 1,332 people, 501 households, and 306 families residing in the town.

As of the census[5] of 2000, there were 1,334 people, 533 households, and 412 families residing in the town.

20.1% of all households were made up of individuals, and 9.6% had someone living alone who was 65 years of age or older.