7 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Britton | 1 | 1,201 | 1,220 | -0.33% | 1,650 | 0.73 | City |
| Agency Village | 2 | 1,170 | 970 | 5.98% | 164 | 7.15 | CDP |
| Long Hollow | 3 | 407 | 395 | 3.56% | 28 | 14.43 | CDP |
| Veblen | 4 | 312 | 316 | -0.32% | 994 | 0.31 | City |
| Langford | 5 | 279 | 283 | -0.36% | 880 | 0.32 | Town |
| Eden | 6 | 90 | 92 | 0% | 584 | 0.15 | Town |
| Lake City | 7 | 43 | 43 | 0% | 196 | 0.22 | Town |
Britton is the largest city in Marshall County, with a population of 1,201.
Lake City is the smallest city in Marshall County.
There are 7 cities in Marshall County, South Dakota.