COUNTY · OK
Adair County, Oklahoma
Adair County is a county in Oklahoma with FIPS code 40001 and an estimated population of 19,627 (Census 2023), 41st largest of 77 in the state.
County facts
- Name
- Adair County
- State
- Oklahoma
- Type
- county
- FIPS code
- 40001
- State FIPS
- 40
- Population (2023)
- 19,627
- Change since 2020
- +0.9%
- State rank
- 41 of 77
Population is the Census Bureau’s Vintage 2023 estimate.
Questions
What is the FIPS code for Adair County?
Adair County, Oklahoma has the five-digit FIPS code 40001: 40 for the state and 001 for the county.
What state is Adair County in?
Adair County is in Oklahoma.
How do I know if an address is in this county?
Use the address lookup. ZIP codes and city names can cross county lines, so an address is the reliable check.
Sources: U.S. Census Bureau geographic reference files; Census Bureau Population Estimates, Vintage 2023. Last reviewed 2026-10-27.