Metro Atlanta, designated by the United States Office of Management and Budget as the Atlanta–Sandy Springs–Alpharetta, GA Metropolitan Statistical Area, is the most populous metropolitan statistical area in the state of Georgia and the eighth-largest in the United States. Its economic, cultural, and demographic center is Atlanta, and its total population was 6,144,050 in the 2021 estimate from the U.S. Census Bureau.
The metro area forms the core of a broader trading area, the Atlanta–Athens-Clarke–Sandy Springs Combined Statistical Area. The Combined Statistical Area spans up to 39 counties in North Georgia, and one county in Alabama, Chambers. The Combined Statistical Area recorded in the 2020 U.S. census a population of 6,930,423. Atlanta is the second-largest metropolitan area in the Census Bureau's Southeast region, behind that of Greater Washington, D.C. It surpassed the Greater Miami area in total population in 2021.
By U.S. Census Bureau standards, the population of the Atlanta region spreads across a metropolitan area of – a land area comparable to that of Massachusetts. Because Georgia contains more counties than any other state except Texas (explained in part by the now-defunct county-unit system of weighing votes in primary elections), area residents live under a heavily decentralized collection of governments. As of the 2000 census, fewer than one in ten residents of the metropolitan area lived inside Atlanta city limits.
A 2006 survey by the Metro Atlanta Chamber of Commerce counted 140 cities and towns in the 28‐county Metropolitan Statistical Area (MSA) in mid-2005. Ten cities – Johns Creek (2006), Milton (2006), Chattahoochee Hills (2007), Dunwoody (2008), Peachtree Corners (2012), Brookhaven (2012), Tucker (2016), Stonecrest (2016), South Fulton (2017), and Mableton (2022) – have incorporated since then, following the lead of Sandy Springs in 2005.
The Atlanta metropolitan area was first defined in 1950 as Fulton, DeKalb, Gwinnett, Cobb and Clayton counties.