Hannahs Mill is an unincorporated community and census-designated place (CDP) in Upson County, Georgia, United States. As of the 2020 census, Hannahs Mill had a population of 3,121.
Hannahs Mill is located at .
According to the United States Census Bureau, the CDP has a total area of , of which is land and 0.23% is water.
Hannahs Mills first appeared as a census designated place in the 1980 U.S. census. It was not listed in the 1990 U.S. census after a portion of the CDP was annexed to Thomaston. It reappeared as a CDP in the 2000 U.S. census.