| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Bozeman | 1 | 59,872 | 53,890 | 1.8% | 2,801 | 21 | City |
| Belgrade | 2 | 13,634 | 10,687 | 4.02% | 2,279 | 6 | City |
| Manhattan | 3 | 2,069 | 2,089 | -0.19% | 1,179 | 2 | Town |
| Three Forks | 4 | 1,912 | 1,982 | -0.42% | 1,329 | 1 | City |
| West Yellowstone | 5 | 1,172 | 1,278 | -1.6% | 1,291 | 1 | Town |
Bozeman is the largest city in Gallatin County, with a population of 59,872.
West Yellowstone is the smallest city in Gallatin County, with a population of 1,172.
There are 5 cities in Gallatin County, Montana.