| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Plentywood | 1 | 1,611 | 1,670 | -0.49% | 1,187 | 1 | City |
| Medicine Lake | 2 | 240 | 245 | -0.41% | 608 | 0 | Town |
| Westby | 3 | 161 | 167 | -0.62% | 286 | 1 | Town |
| Outlook | 4 | 82 | 86 | -1.2% | 66 | 1 | Town |
Plentywood is the largest city in Sheridan County, with a population of 1,611.
Outlook is the smallest city in Sheridan County, with a population of 82.
There are 4 cities in Sheridan County, Montana.