As of 2019, Georgia's most populous county is Fulton County, home to the major metropolitan city of Atlanta, with a population of 1,041,423. This represents a population increase of 12.49% since the 2010 census. After Fulton County, the largest counties in Georgia are Gwinnett County (920,260), Cobb County (755,754), and DeKalb County (753,253). These are the only counties in Georgia with a population of more than 500,000. Of these counties, Gwinnett County has seen the biggest population growth over the last nine years of 13.86%.
The least populous county in Georgia is Taliaferro County with just 1,680 people. The county has declined in population by 4.40% since the last census. Other small counties with under 5,000 residents include Quitman County (2,358), Webster County (2,605), Clay County (2,962), Glascock County (3,062), Baker County (3,200), and Echols County). All of these counties have reported a declining population since the 2010 census.
Long County has had the highest growth rate in Georgia since the last census with an impressive increase of 29.58%. The population has grown from 14,464 in 2010 to 19,014 in 2019. Two other Georgia counties have reported population growth exceeding 20%: Forsyth County has grown 28.96% since the last census to 227,967 to become the state's 8th largest county and Columbia County has grown 21.26% to reach 151,579 residents.