Where is Johnson County?

12 Johnson Counties in 12 states · 1.3 million people (2025)

There are 12 counties named Johnson County in the United States, in Arkansas, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Missouri, Nebraska, Tennessee, Texas and Wyoming. The most populous is Johnson County, Kansas (county seat: Olathe), with 636,906 people in 2025. 5 of them are named after Richard Mentor Johnson, vice president of the United States from 1837 to 1841.

Map of the United States showing where all 12 Johnson Counties are, labeled by state
Every Johnson 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 12 Johnson Counties

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

StateCounty seatPopulation 2025Land area (sq mi)EstablishedNamed after
Johnson County, ArkansasClarksville26,2256611833Benjamin Johnson
Johnson County, GeorgiaWrightsville9,3103031858Herschel V. Johnson
Johnson County, IllinoisVienna13,3633441812Richard Mentor Johnson
Johnson County, IndianaFranklin174,2623201823John Johnson
Johnson County, IowaIowa City160,0446131837Richard Mentor Johnson
Johnson County, KansasOlathe636,9064741855Thomas Johnson
Johnson County, KentuckyPaintsville22,0512621843Richard Mentor Johnson
Johnson County, MissouriWarrensburg56,6708291834Richard Mentor Johnson
Johnson County, NebraskaTecumseh5,2183761857Richard Mentor Johnson
Johnson County, TennesseeMountain City18,7182981836Thomas Johnson
Johnson County, TexasCleburne218,0487251854Middleton Johnson
Johnson County, WyomingBuffalo8,9084,1541875E. P. Johnson

Questions about Johnson Counties

How many Johnson Counties are there?

There are 12 Johnson Counties in the United States, in Arkansas, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Missouri, Nebraska, Tennessee, Texas and Wyoming.

Which Johnson County is the largest?

By population, Johnson County, Kansas (636,906 people in 2025). By land area, Johnson County, Wyoming (4,154 sq mi).

Which Johnson County is the oldest?

Johnson County, Illinois, established in 1812. The newest is Johnson County, Wyoming (1875).

Why are there so many Johnson Counties?

5 of the 12 are named after Richard Mentor Johnson, vice president of the United States from 1837 to 1841. Many counties took their names from the same founders, presidents and generals as new states were organized.

How do I find out which Johnson 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