CITY · AZ

What county is Flagstaff, AZ in?

Flagstaff, AZ is mostly in Coconino County. County FIPS code 04005, population 144,472 (2023 estimate).

County details

City: Flagstaff, Arizona
Primary county: Coconino County
FIPS code: 04005
County population: 144,472

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

Questions

What county is Flagstaff in?

Flagstaff, AZ is mostly in Coconino County.

What is the county seat of Coconino 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.