20 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| De Smet | 1 | 1,029 | 1,068 | -0.77% | 889 | 1 | City |
| Arlington | 2 | 926 | 924 | 0% | 539 | 2 | City |
| Lake Preston | 3 | 608 | 590 | 0.5% | 801 | 1 | City |
| De Smet | 4 | 324 | 306 | 1.25% | 5 | 63 | Township |
| Spring Lake | 5 | 304 | 299 | 0% | 4 | 80 | Township |
| Iroquois | 6 | 295 | 300 | -0.34% | 476 | 1 | City |
| Baker | 7 | 234 | 226 | 0.86% | 3 | 70 | Township |
| Badger | 8 | 222 | 215 | 0.45% | 4 | 53 | Township |
| Denver | 9 | 216 | 208 | 0.47% | 3 | 65 | Township |
| Hartland | 10 | 168 | 166 | -1.18% | 3 | 63 | Township |
| Spirit Lake | 11 | 159 | 152 | 0.63% | 3 | 60 | Township |
| Badger | 12 | 151 | 149 | 0.67% | 4 | 37 | Township |
| Le Sueur | 13 | 147 | 140 | 0.68% | 2 | 63 | Township |
| Badger | 14 | 136 | 129 | 0.74% | 128 | 1 | Town |
| Oldham | 15 | 117 | 122 | -0.85% | 476 | 0 | City |
| Mathews | 16 | 113 | 107 | 0.89% | 1 | 84 | Township |
| Iroquois | 17 | 65 | 60 | 3.17% | 2 | 41 | Township |
| Manchester | 18 | 62 | 60 | 0% | 1 | 56 | Township |
| Esmond | 19 | 47 | 46 | 0% | 1 | 79 | Township |
| Erwin | 20 | 39 | 38 | 0% | 82 | 0 | Town |
De Smet is the largest city in Kingsbury County, with a population of 1,029.
Erwin is the smallest city in Kingsbury County, with a population of 39.
There are 20 cities in Kingsbury County, South Dakota.