8 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| North Eagle Butte | 1 | 1,594 | 1,838 | -1.48% | 181 | 8.82 | CDP |
| Eagle Butte | 2 | 1,213 | 1,250 | -0.57% | 891 | 1.36 | City |
| Timber Lake | 3 | 518 | 512 | 0.19% | 848 | 0.61 | City |
| La Plant | 4 | 332 | 305 | 3.11% | 35 | 9.45 | CDP |
| Swift Bird | 5 | 224 | 220 | 7.18% | 456 | 0.49 | CDP |
| Whitehorse | 6 | 148 | 245 | 0% | 54 | 2.74 | CDP |
| Isabel | 7 | 145 | 145 | 0% | 172 | 0.84 | Town |
| Lantry | 8 | 49 | 48 | 6.52% | 118 | 0.41 | CDP |
North Eagle Butte is the largest city in Dewey County, with a population of 1,594.
Lantry is the smallest city in Dewey County.
There are 8 cities in Dewey County, South Dakota.