3 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Arco | 1 | 919 | 879 | 0.88% | 860 | 1 | City |
| Moore | 2 | 178 | 163 | 1.71% | 627 | 0 | City |
| Butte City | 3 | 87 | 79 | 1.16% | 515 | 0 | City |
Arco is the largest city in Butte County, with a population of 919.
Butte City is the smallest city in Butte County, with a population of 87.
There are 3 cities in Butte County, Idaho.