5 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Hot Springs | 1 | 3,712 | 3,399 | 1.42% | 855 | 4 | City |
| Edgemont | 2 | 774 | 729 | 1.04% | 560 | 1 | City |
| Oelrichs | 3 | 129 | 119 | 1.57% | 353 | 0 | Town |
| Provo | 4 | 36 | 32 | 2.86% | 1 | 36 | Township |
| Argentine | 5 | 18 | 17 | 0% | 1 | 36 | Township |
Hot Springs is the largest city in Fall River County, with a population of 3,712.
Argentine is the smallest city in Fall River County, with a population of 18.
There are 5 cities in Fall River County, South Dakota.