| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Hallock | 1 | 856 | 895 | -1.04% | 402 | 2 | City |
| Karlstad | 2 | 671 | 708 | -1.18% | 446 | 2 | City |
| Lancaster | 3 | 338 | 355 | -1.17% | 145 | 2 | City |
| Lake Bronson | 4 | 169 | 179 | -1.17% | 319 | 1 | City |
| Kennedy | 5 | 165 | 175 | -1.2% | 369 | 0 | City |
| Halma | 6 | 55 | 58 | -1.79% | 59 | 1 | City |
| St. Vincent | 7 | 48 | 51 | -2.04% | 47 | 1 | City |
| Humboldt | 8 | 38 | 41 | -2.56% | 342 | 0 | City |
| Donaldson | 9 | 18 | 20 | -5.26% | 79 | 0 | City |
Hallock is the largest city in Kittson County, with a population of 856.
Donaldson is the smallest city in Kittson County, with a population of 18.
There are 9 cities in Kittson County, Minnesota.