2 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Miles City | 1 | 8,490 | 8,360 | 0.31% | 2,525 | 3.36 | City |
| Ismay | 2 | 19 | 19 | 0% | 45 | 0.42 | Town |
Miles City is the largest city in Custer County, with a population of 8,490.
Ismay is the smallest city in Custer County.
There are 2 cities in Custer County, Montana.