42 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Sisseton | 1 | 2,382 | 2,471 | -0.75% | 1,497 | 1.59 | City |
| Goodwill township | 2 | 920 | 907 | 0.66% | 25 | 36.24 | Township |
| Sisseton township | 3 | 795 | 780 | 0.76% | 23 | 34.50 | Township |
| Long Hollow township | 4 | 428 | 415 | 0.94% | 12 | 35.73 | Township |
| Wilmot | 5 | 418 | 432 | -0.71% | 784 | 0.53 | City |
| Lockwood township | 6 | 365 | 356 | 0.83% | 17 | 21.62 | Township |
| Rosholt | 7 | 362 | 377 | -0.82% | 1,223 | 0.30 | Town |
| Agency township | 8 | 305 | 301 | 0.33% | 8 | 35.99 | Township |
| Geneseo township | 9 | 299 | 288 | 1.01% | 9 | 33.69 | Township |
| Summit | 10 | 271 | 285 | -1.09% | 495 | 0.55 | Town |
| Lake township | 11 | 265 | 256 | 1.15% | 7 | 36.83 | Township |
| Lawrence township | 12 | 230 | 226 | 0.44% | 10 | 22.21 | Township |
| New Effington | 13 | 221 | 233 | -0.9% | 847 | 0.26 | Town |
| Summit township | 14 | 197 | 187 | 1.55% | 6 | 34.97 | Township |
| Grant township | 15 | 180 | 176 | 0.56% | 5 | 35.76 | Township |
| Peever | 16 | 171 | 176 | -0.58% | 1,379 | 0.12 | Town |
| Victor township | 17 | 167 | 163 | 0.6% | 4 | 47.45 | Township |
| Harmon township | 18 | 153 | 150 | 0.66% | 2 | 61.50 | Township |
| Easter township | 19 | 147 | 143 | 0.68% | 4 | 33.37 | Township |
| Spring Grove township | 20 | 142 | 139 | 0% | 4 | 35.99 | Township |
| White Rock township | 21 | 136 | 128 | 2.26% | 2 | 57.73 | Township |
| Peever Flats | 22 | 134 | 187 | 7.2% | 1,787 | 0.07 | CDP |
| Lien township | 23 | 132 | 124 | 2.33% | 3 | 47.47 | Township |
| Garfield township | 24 | 127 | 124 | 0.79% | 4 | 34.89 | Township |
| Becker township | 25 | 111 | 112 | 0% | 4 | 28.48 | Township |
| Springdale township | 26 | 110 | 111 | 0% | 3 | 34.76 | Township |
| Dry Wood Lake township | 27 | 104 | 102 | 0.97% | 3 | 31.62 | Township |
| Enterprise township | 28 | 101 | 99 | 1% | 3 | 35.81 | Township |
| Hart township | 29 | 101 | 101 | 0% | 3 | 35.88 | Township |
| Minnesota township | 30 | 97 | 97 | 0% | 2 | 46.90 | Township |
| Norway township | 31 | 92 | 90 | 1.1% | 2 | 48.21 | Township |
| Ortley township | 32 | 88 | 85 | 1.15% | 3 | 33.61 | Township |
| Claire City | 33 | 79 | 83 | -1.25% | 432 | 0.18 | Town |
| Sisseton township | 34 | 74 | 69 | 1.37% | 2 | 34.97 | Township |
| Corona | 35 | 68 | 65 | 1.49% | 269 | 0.25 | Town |
| Lee township | 36 | 66 | 66 | 0% | 2 | 28.14 | Township |
| One Road township | 37 | 63 | 60 | 1.61% | 2 | 34.42 | Township |
| Alto township | 38 | 60 | 53 | 5.26% | 2 | 34.92 | Township |
| Bossko township | 39 | 53 | 48 | 3.92% | 1 | 36.02 | Township |
| Ortley | 40 | 47 | 49 | 0% | 21 | 2.24 | Town |
| Summit township | 41 | 39 | 34 | 5.41% | 1 | 32.33 | Township |
| White Rock | 42 | 7 | 7 | 0% | 4 | 1.57 | Town |
Sisseton is the largest city in Roberts County, with a population of 2,382.
White Rock is the smallest city in Roberts County.
There are 42 cities in Roberts County, South Dakota.