Montana Counties, Demographics & Geography
Complete official guide to all 56 counties in Montana (MT). Explore 2024 US Census population estimates, county seats, FIPS codes, land areas, and interactive mapping tools powered by GeoMap Suite.
Montana County Breakdown
Showing 6 of 6 documented counties and seats.
County Name | FIPS | County Seat | Population (Census) | Land Area | Quick Tool |
|---|---|---|---|---|---|
| Yellowstone County (Billings) | 30111 | Billings | 164,725 | 2,635 sq mi | Lookup |
| Gallatin County (Bozeman) | 30031 | Bozeman | 118,960 | 2,606 sq mi | Lookup |
| Missoula County | 30063 | Missoula | 117,922 | 2,598 sq mi | Lookup |
| Flathead County (Kalispell) | 30029 | Kalispell | 104,357 | 5,099 sq mi | Lookup |
| Cascade County (Great Falls) | 30013 | Great Falls | 84,411 | 2,698 sq mi | Lookup |
| Lewis and Clark County (Helena) | 30049 | Helena | 70,973 | 3,461 sq mi | Lookup |
Geographic Structure of Montana Counties
County Administration & Governance
In Montana, county governments manage vital public infrastructure, tax assessments, law enforcement, judicial courts, election administration, and public records. The county seat (Billings and other municipal headquarters) houses the primary courthouse, commissioners, and sheriff’s department.
All Montana counties carry a unique 5-digit Federal Information Processing Standard (FIPS) code, where the first two digits (30) designate the state and the remaining three digits identify each specific jurisdiction.
Geographic & Demographic Highlights
- Most Populous County:Yellowstone County (Billings) (164,725 residents)
- Largest by Land Area:Flathead County (Kalispell) (5,099 sq mi)
- State Capital:Helena
- Census Bureau Region:West United States
Demographic calculations derive from the United States Census Bureau 2024 Population Estimates Program (PEP) and TIGER/Line geographic boundary files.