Forsyth County is a county in the Northeast region of the U.S. state of Georgia. Suburban and exurban in character, Forsyth County lies within the Atlanta metropolitan area. The county's only incorporated city and county seat is Cumming. At the 2020 census, the population was 251,283. Forsyth was the fastest-growing county in Georgia and the 15th fastest-growing county in the United States between 2010 and 2019.