3 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Thief River Falls | 1 | 8,811 | 8,836 | -0.06% | 1,468 | 6 | City |
| St. Hilaire | 2 | 248 | 273 | -1.98% | 317 | 0.78 | City |
| Goodridge | 3 | 105 | 110 | -0.94% | 559 | 0.19 | City |
Thief River Falls is the largest city in Pennington County, with a population of 8,811.
Goodridge is the smallest city in Pennington County.
There are 3 cities in Pennington County, Minnesota.