17 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Bozeman | 1 | 59,614 | 53,841 | 1.98% | 2,789 | 21.38 | City |
| Belgrade | 2 | 13,721 | 10,691 | 4.62% | 2,820 | 4.87 | City |
| Four Corners | 3 | 6,252 | 4,859 | 3.42% | 577 | 10.84 | CDP |
| Big Sky | 4 | 2,954 | 3,054 | 1.48% | 25 | 120 | CDP |
| King Arthur Park | 5 | 2,357 | 1,933 | 4.8% | 5,091 | 0.46 | CDP |
| Manhattan | 6 | 2,121 | 2,090 | 0.28% | 1,209 | 1.75 | Town |
| Three Forks | 7 | 1,988 | 1,982 | 0.05% | 1,382 | 1.44 | City |
| West Yellowstone | 8 | 1,189 | 1,271 | -1.33% | 1,309 | 0.91 | Town |
| Churchill | 9 | 1,126 | 989 | 1.35% | 317 | 3.55 | CDP |
| Gallatin Gateway | 10 | 894 | 798 | 0.34% | 153 | 5.85 | CDP |
| Gallatin River Ranch | 11 | 229 | 120 | 7.01% | 32 | 7.08 | CDP |
| Springhill | 12 | 216 | 198 | 2.86% | 78 | 2.78 | CDP |
| Willow Creek | 13 | 211 | 216 | 0% | 77 | 2.73 | CDP |
| Logan | 14 | 163 | 17 | 7.24% | 327 | 0.50 | CDP |
| Amsterdam | 15 | 155 | 169 | -1.27% | 57 | 2.71 | CDP |
| Sedan | 16 | 142 | 56 | 6.77% | 2 | 60.99 | CDP |
| Hebgen Lake Estates | 17 | 119 | 66 | 7.21% | 647 | 0.18 | CDP |
Bozeman is the largest city in Gallatin County, with a population of 59,614.
Hebgen Lake Estates is the smallest city in Gallatin County.
There are 17 cities in Gallatin County, Montana.