8 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| International Falls | 1 | 5,357 | 5,780 | -1.29% | 788 | 7 | City |
| Birchdale | 2 | 978 | 922 | 1.03% | 30 | 33 | Township |
| Ranier | 3 | 527 | 566 | -1.13% | 493 | 1 | City |
| Littlefork | 4 | 514 | 553 | -1.15% | 432 | 1 | City |
| Big Falls | 5 | 168 | 177 | -0.59% | 28 | 6 | City |
| Northome | 6 | 152 | 158 | -0.65% | 104 | 1 | City |
| Kabetogama | 7 | 141 | 139 | 0.71% | 8 | 17 | Township |
| Mizpah | 8 | 52 | 54 | 0% | 17 | 3 | City |
International Falls is the largest city in Koochiching County, with a population of 5,357.
Mizpah is the smallest city in Koochiching County, with a population of 52.
There are 8 cities in Koochiching County, Minnesota.