Where is Osage County?

3 Osage Counties in 3 states · 76,098 people (2025)

There are 3 counties named Osage County in the United States, in Kansas, Missouri and Oklahoma. The most populous is Osage County, Oklahoma (county seat: Pawhuska), with 46,794 people in 2025. 2 of them are named after Osage River, river in Missouri, United States.

Map of the United States showing where all 3 Osage Counties are, labeled by state
Every Osage County in the United States (red), labeled with its state. Boundaries: U.S. Census Bureau, 2025. Free to use with attribution (CC BY 4.0).

All 3 Osage Counties

Sorted by state. Each link opens the county's map.

StateCounty seatPopulation 2025Land area (sq mi)EstablishedNamed after
Osage County, KansasLyndon15,6937061855Osage River
Osage County, MissouriLinn13,6116071841Osage River
Osage County, OklahomaPawhuska46,7942,2471907Osage Nation

Questions about Osage Counties

How many Osage Counties are there?

There are 3 Osage Counties in the United States, in Kansas, Missouri and Oklahoma.

Which Osage County is the largest?

By population, Osage County, Oklahoma (46,794 people in 2025). By land area, Osage County, Oklahoma (2,247 sq mi).

Which Osage County is the oldest?

Osage County, Missouri, established in 1841. The newest is Osage County, Oklahoma (1907).

Why are there so many Osage Counties?

2 of the 3 are named after Osage River, river in Missouri, United States. Many counties took their names from the same founders, presidents and generals as new states were organized.

How do I find out which Osage County an address is in?

Open the county map of the state: it has a search box for cities, towns and ZIP codes. On a phone, the "what county am I in" tool on our sister site uses your location.

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Other common county names