5 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Roundup | 1 | 2,101 | 1,748 | 3.5% | 1,625 | 1.29 | City |
| Klein | 2 | 283 | 156 | 2.91% | 22 | 12.85 | CDP |
| Melstone | 3 | 155 | 130 | 3.33% | 252 | 0.61 | Town |
| Camp Three | 4 | 150 | 150 | -1.32% | 34 | 4.45 | CDP |
| Musselshell | 5 | 41 | 23 | 7.89% | 16 | 2.55 | CDP |
Roundup is the largest city in Musselshell County, with a population of 2,101.
Musselshell is the smallest city in Musselshell County.
There are 5 cities in Musselshell County, Montana.