| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Belle Fourche | 1 | 5,842 | 5,652 | 0.88% | 644 | 9 | City |
| Newell | 2 | 571 | 578 | 0.18% | 564 | 1 | City |
| Nisland | 3 | 206 | 206 | 0% | 766 | 0 | Town |
Belle Fourche is the largest city in Butte County, with a population of 5,842.
Nisland is the smallest city in Butte County, with a population of 206.
There are 3 cities in Butte County, South Dakota.