14 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Chatfield | 1 | 3,033 | 3,003 | 0.17% | 1,171 | 3 | City |
| Spring Valley | 2 | 2,439 | 2,457 | -0.12% | 825 | 3 | City |
| Rushford | 3 | 1,846 | 1,863 | -0.16% | 1,119 | 2 | City |
| Preston | 4 | 1,314 | 1,319 | -0.08% | 533 | 2 | City |
| Harmony | 5 | 1,022 | 1,046 | -0.39% | 917 | 1 | City |
| Rushford Village | 6 | 801 | 795 | 0.13% | 24 | 34 | City |
| Lanesboro | 7 | 706 | 724 | -0.42% | 466 | 2 | City |
| Mabel | 8 | 699 | 717 | -0.43% | 1,453 | 0 | City |
| Wykoff | 9 | 429 | 431 | 0% | 460 | 1 | City |
| Fountain | 10 | 405 | 408 | 0% | 407 | 1 | City |
| Canton | 11 | 313 | 312 | 0% | 304 | 1 | City |
| Peterson | 12 | 224 | 232 | -0.44% | 472 | 0 | City |
| Ostrander | 13 | 223 | 231 | -0.45% | 469 | 0 | City |
| Whalan | 14 | 70 | 66 | 1.45% | 163 | 0 | City |
Chatfield is the largest city in Fillmore County, with a population of 3,033.
Whalan is the smallest city in Fillmore County, with a population of 70.
There are 14 cities in Fillmore County, Minnesota.