3 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Highmore | 1 | 640 | 672 | -1.08% | 340 | 2 | City |
| Valley | 2 | 13 | 12 | 8.33% | 0.00 | 36 | Township |
| William Hamilton | 3 | 7 | 7 | 0% | 0.00 | 36 | Township |
Highmore is the largest city in Hyde County, with a population of 640.
William Hamilton is the smallest city in Hyde County, with a population of 7.
There are 3 cities in Hyde County, South Dakota.