Where is Custer County?

6 Custer Counties in 6 states · 70,366 people (2025)

There are 6 counties named Custer County in the United States, in Colorado, Idaho, Montana, Nebraska, Oklahoma and South Dakota. The most populous is Custer County, Oklahoma (county seat: Arapaho), with 28,175 people in 2025. 6 of them are named after George Armstrong Custer, United States cavalry commander (1839–1876).

All 6 Custer Counties

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

State	County seat	Population 2025	Land area (sq mi)	Established	Named after
Custer County, Colorado	Westcliffe	5,590	739	1877	George Armstrong Custer
Custer County, Idaho	Challis	4,636	4,922	1881	George Armstrong Custer
Custer County, Montana	Miles City	12,034	3,783	1865	George Armstrong Custer
Custer County, Nebraska	Broken Bow	10,500	2,576	1877	George Armstrong Custer
Custer County, Oklahoma	Arapaho	28,175	989	1892	George Armstrong Custer
Custer County, South Dakota	Custer	9,431	1,557	1875	George Armstrong Custer

Questions about Custer Counties

How many Custer Counties are there?

There are 6 Custer Counties in the United States, in Colorado, Idaho, Montana, Nebraska, Oklahoma and South Dakota.

Which Custer County is the largest?

By population, Custer County, Oklahoma (28,175 people in 2025). By land area, Custer County, Idaho (4,922 sq mi).

Which Custer County is the oldest?

Custer County, Montana, established in 1865. The newest is Custer County, Oklahoma (1892).

Why are there so many Custer Counties?

6 of the 6 are named after George Armstrong Custer, United States cavalry commander (1839–1876). Many counties took their names from the same founders, presidents and generals as new states were organized.

How do I find out which Custer 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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