Upson County is a county located in the west central Piedmont portion of the U.S. state of Georgia. As of the 2020 census, the population was 27,700. The county seat is Thomaston. The county was created on December 15, 1824.

Thomaston is a city in and the county seat of Upson County, Georgia, United States. The population was 9,170 at the 2010 census. It is the principal city of and is included in the Thomaston, Georgia Micropolitan Statistical Area, which is included in the Atlanta - Sandy Springs (GA) - Gainesville (GA) - Alabama (partial) CSA.