| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| International Falls | 1 | 5,412 | 5,779 | -1.26% | 796 | 7 | City |
| Ranier | 2 | 533 | 570 | -1.48% | 498 | 1 | City |
| Littlefork | 3 | 523 | 556 | -1.32% | 439 | 1 | City |
| Big Falls | 4 | 168 | 177 | -1.18% | 28 | 6 | City |
| Northome | 5 | 154 | 158 | -0.65% | 106 | 1 | City |
| Mizpah | 6 | 50 | 52 | -1.96% | 17 | 3 | City |
International Falls is the largest city in Koochiching County, with a population of 5,412.
Mizpah is the smallest city in Koochiching County, with a population of 50.
There are 6 cities in Koochiching County, Minnesota.