| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Wasco | 1 | 464 | 418 | 1.53% | 460 | 1 | City |
| Moro | 2 | 409 | 370 | 1.49% | 825 | 0 | City |
| Rufus | 3 | 297 | 266 | 1.71% | 251 | 1 | City |
| Grass Valley | 4 | 173 | 152 | 1.76% | 339 | 1 | City |
Wasco is the largest city in Sherman County, with a population of 464.
Grass Valley is the smallest city in Sherman County, with a population of 173.
There are 4 cities in Sherman County, Oregon.