Where is Gallatin County?

3 Gallatin Counties in 3 states · 142,196 people (2025)

There are 3 counties named Gallatin County in the United States, in Illinois, Kentucky and Montana. The most populous is Gallatin County, Montana (county seat: Bozeman), with 128,740 people in 2025. 3 of them are named after Albert Gallatin, Swiss and American politician, diplomat and scholar (1761-1849).

Map of the United States showing where all 3 Gallatin Counties are, labeled by state
Every Gallatin 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 Gallatin Counties

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

StateCounty seatPopulation 2025Land area (sq mi)EstablishedNamed after
Gallatin County, IllinoisShawneetown4,6163231812Albert Gallatin
Gallatin County, KentuckyWarsaw8,840981798Albert Gallatin
Gallatin County, MontanaBozeman128,7402,6051865Albert Gallatin

Questions about Gallatin Counties

How many Gallatin Counties are there?

There are 3 Gallatin Counties in the United States, in Illinois, Kentucky and Montana.

Which Gallatin County is the largest?

By population, Gallatin County, Montana (128,740 people in 2025). By land area, Gallatin County, Montana (2,605 sq mi).

Which Gallatin County is the oldest?

Gallatin County, Kentucky, established in 1798. The newest is Gallatin County, Montana (1865).

Why are there so many Gallatin Counties?

3 of the 3 are named after Albert Gallatin, Swiss and American politician, diplomat and scholar (1761-1849). Many counties took their names from the same founders, presidents and generals as new states were organized.

How do I find out which Gallatin 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