41 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Sisseton | 1 | 2,411 | 2,473 | -0.41% | 1,515 | 2 | City |
| Goodwill | 2 | 924 | 907 | 0.43% | 25 | 36 | Township |
| Sisseton | 3 | 797 | 780 | 0.63% | 23 | 34 | Township |
| Long Hollow | 4 | 426 | 415 | 0.47% | 12 | 36 | Township |
| Wilmot | 5 | 422 | 433 | -0.47% | 792 | 1 | City |
| Lockwood | 6 | 371 | 356 | 1.09% | 17 | 22 | Township |
| Rosholt | 7 | 368 | 380 | -0.54% | 1,243 | 0 | Town |
| Agency | 8 | 321 | 301 | 1.58% | 9 | 36 | Township |
| Geneseo | 9 | 300 | 285 | 1.01% | 9 | 34 | Township |
| Summit | 10 | 275 | 284 | -0.36% | 502 | 1 | Town |
| Lake | 11 | 267 | 258 | 0.75% | 7 | 37 | Township |
| Lawrence | 12 | 229 | 224 | 0.44% | 10 | 22 | Township |
| New Effington | 13 | 225 | 233 | -0.44% | 862 | 0 | Town |
| Summit | 14 | 183 | 185 | -1.08% | 5 | 35 | Township |
| Grant | 15 | 173 | 171 | 0% | 5 | 36 | Township |
| Peever | 16 | 173 | 176 | 0% | 1,395 | 0 | Town |
| Victor | 17 | 165 | 160 | 0.61% | 3 | 47 | Township |
| Harmon | 18 | 154 | 150 | 0.65% | 3 | 62 | Township |
| Spring Grove | 19 | 147 | 141 | 0.68% | 4 | 36 | Township |
| Easter | 20 | 146 | 144 | 0% | 4 | 33 | Township |
| White Rock | 21 | 132 | 127 | 0.76% | 2 | 58 | Township |
| Garfield | 22 | 124 | 123 | 0% | 4 | 35 | Township |
| Lien | 23 | 123 | 121 | 0% | 3 | 47 | Township |
| Becker | 24 | 121 | 113 | 2.54% | 4 | 28 | Township |
| Springdale | 25 | 112 | 110 | 0.9% | 3 | 35 | Township |
| Dry Wood Lake | 26 | 104 | 104 | 0% | 3 | 32 | Township |
| Minnesota | 27 | 103 | 103 | 0% | 2 | 47 | Township |
| Enterprise | 28 | 102 | 102 | 0% | 3 | 36 | Township |
| Hart | 29 | 101 | 101 | 0% | 3 | 36 | Township |
| Norway | 30 | 90 | 90 | 0% | 2 | 48 | Township |
| Ortley | 31 | 87 | 86 | 0% | 3 | 34 | Township |
| Claire City | 32 | 81 | 84 | 0% | 443 | 0 | Town |
| Corona | 33 | 72 | 66 | 1.41% | 285 | 0 | Town |
| Sisseton | 34 | 71 | 68 | 0% | 2 | 35 | Township |
| Lee | 35 | 68 | 68 | 0% | 2 | 28 | Township |
| One Road | 36 | 62 | 61 | 0% | 2 | 34 | Township |
| Alto | 37 | 61 | 53 | 5.17% | 2 | 35 | Township |
| Ortley | 38 | 50 | 49 | 0% | 22 | 2 | Town |
| Bossko | 39 | 49 | 48 | 0% | 1 | 36 | Township |
| Summit | 40 | 39 | 34 | 5.41% | 1 | 32 | Township |
| White Rock | 41 | 7 | 7 | 0% | 4 | 2 | Town |
Sisseton is the largest city in Roberts County, with a population of 2,411.
White Rock is the smallest city in Roberts County, with a population of 7.
There are 41 cities in Roberts County, South Dakota.