20 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| De Smet | 1 | 1,034 | 1,063 | -0.58% | 893 | 1.16 | City |
| Arlington | 2 | 933 | 920 | 0.32% | 543 | 1.72 | City |
| Lake Preston | 3 | 627 | 591 | 1.13% | 826 | 0.76 | City |
| De Smet township | 4 | 325 | 309 | 0.62% | 5 | 62.67 | Township |
| Spring Lake township | 5 | 304 | 299 | 0% | 4 | 79.63 | Township |
| Iroquois | 6 | 293 | 298 | -0.34% | 473 | 0.62 | City |
| Baker township | 7 | 230 | 224 | 0.44% | 3 | 69.74 | Township |
| Badger township | 8 | 223 | 215 | 0.45% | 4 | 53.27 | Township |
| Denver township | 9 | 220 | 211 | 0.92% | 3 | 65.18 | Township |
| Hartland township | 10 | 174 | 166 | 0.58% | 3 | 63.01 | Township |
| Spirit Lake township | 11 | 157 | 152 | 0% | 3 | 60.48 | Township |
| Badger township | 12 | 149 | 149 | 0% | 4 | 37.19 | Township |
| Le Sueur township | 13 | 149 | 141 | 0.68% | 2 | 63.16 | Township |
| Badger | 14 | 137 | 129 | 1.48% | 129 | 1.06 | Town |
| Oldham | 15 | 117 | 121 | -0.85% | 476 | 0.25 | City |
| Mathews township | 16 | 112 | 108 | 0% | 1 | 84.44 | Township |
| Manchester township | 17 | 66 | 61 | 1.54% | 1 | 55.67 | Township |
| Iroquois township | 18 | 63 | 61 | 0% | 2 | 41.18 | Township |
| Esmond township | 19 | 45 | 46 | -2.17% | 1 | 78.51 | Township |
| Erwin | 20 | 40 | 39 | 0% | 84 | 0.48 | Town |
De Smet is the largest city in Kingsbury County, with a population of 1,034.
Erwin is the smallest city in Kingsbury County.
There are 20 cities in Kingsbury County, South Dakota.