Soperton is a city in Treutlen County, Georgia, United States. The population was 2,889 in 2020. The city is the county seat of Treutlen …Soperton is a city in Treutlen County, Georgia, United States. The population was 2,889 in 2020. The city is the county seat of Treutlen County. A post office was established at Soperton in 1902. The city was named after Benjamin Franklin Soper, a railroad official.