30 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Wagner | 1 | 1,387 | 1,484 | -1.35% | 747 | 1.86 | City |
| Platte | 2 | 1,208 | 1,293 | -1.39% | 1,148 | 1.05 | City |
| Highland township | 3 | 788 | 786 | 0.13% | 22 | 36.43 | Township |
| White Swan township | 4 | 747 | 728 | 1.08% | 9 | 79.28 | Township |
| Lake Andes | 5 | 667 | 712 | -1.33% | 894 | 0.75 | City |
| Lawrence township | 6 | 494 | 485 | 0.82% | 14 | 35.61 | Township |
| Bryan township | 7 | 390 | 386 | 0.52% | 11 | 35.73 | Township |
| La Roche township | 8 | 359 | 361 | -0.28% | 6 | 60.43 | Township |
| Platte township | 9 | 300 | 295 | 0.67% | 9 | 34.59 | Township |
| Wahehe township | 10 | 260 | 255 | 0.39% | 9 | 28.10 | Township |
| Choteau Creek township | 11 | 235 | 238 | -0.42% | 4 | 62.28 | Township |
| Pickstown | 12 | 230 | 225 | 0.44% | 375 | 0.61 | Town |
| Goose Lake township | 13 | 213 | 212 | 0.47% | 3 | 64.09 | Township |
| Rouse township | 14 | 182 | 179 | 0.55% | 3 | 60.73 | Township |
| Lone Tree township | 15 | 167 | 164 | 0.6% | 5 | 35.81 | Township |
| Ree township | 16 | 150 | 146 | 1.35% | 3 | 46.56 | Township |
| Geddes | 17 | 148 | 158 | -1.33% | 204 | 0.73 | City |
| Marty | 18 | 146 | 265 | -10.43% | 45 | 3.22 | CDP |
| Jackson township | 19 | 135 | 127 | 2.27% | 2 | 59.99 | Township |
| Rhoda township | 20 | 124 | 122 | 0.81% | 3 | 42.77 | Township |
| Plain Center township | 21 | 121 | 119 | 0.83% | 3 | 35.20 | Township |
| Darlington township | 22 | 108 | 106 | 0.93% | 3 | 38.62 | Township |
| Moore township | 23 | 70 | 73 | -1.41% | 1 | 62.13 | Township |
| Ravinia | 24 | 69 | 69 | 0% | 277 | 0.25 | Town |
| Dante | 25 | 67 | 69 | 0% | 134 | 0.50 | Town |
| Forbes township | 26 | 61 | 64 | -1.61% | 2 | 29.45 | Township |
| Signal township | 27 | 59 | 59 | 0% | 1 | 47.57 | Township |
| Hamilton township | 28 | 53 | 53 | 0% | 2 | 22.48 | Township |
| Kennedy township | 29 | 53 | 53 | 0% | 2 | 34.42 | Township |
| Lake George township | 30 | 43 | 38 | 4.88% | 1 | 29.57 | Township |
Wagner is the largest city in Charles Mix County, with a population of 1,387.
Lake George township is the smallest city in Charles Mix County.
There are 30 cities in Charles Mix County, South Dakota.