CITY · CO

What county is Aurora, CO in?

Aurora, CO is mostly in Arapahoe County. County FIPS code 08005, population 656,061 (2023 estimate).

County details

City: Aurora, Colorado
Primary county: Arapahoe County
FIPS code: 08005
County population: 656,061

Some cities extend into more than one county. Aurora is placed in the county that contains its center. For a specific address, use the address lookup.

Questions

What county is Aurora in?

Aurora, CO is mostly in Arapahoe County.

What is the county seat of Arapahoe County?

County seats are not part of the data on this site. Check the county’s official website.

Can a city be in two counties?

Yes. Large cities such as Houston and Atlanta cross county lines. The address lookup shows the exact county for any street address.

Sources: U.S. Census Bureau geographic reference files; FCC Area API; Census Bureau Population Estimates, Vintage 2023. Last reviewed 2026-10-27.