| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Mankato | 1 | 46,917 | 44,634 | 0.83% | 2,328 | 20 | City |
| North Mankato | 2 | 14,132 | 14,300 | -0.23% | 2,195 | 6 | City |
| Eagle Lake | 3 | 3,360 | 3,291 | 0.09% | 1,745 | 2 | City |
| Lake Crystal | 4 | 2,449 | 2,541 | -0.85% | 1,436 | 2 | City |
| Mapleton | 5 | 1,602 | 1,706 | -1.23% | 1,172 | 1 | City |
| Madison Lake | 6 | 1,327 | 1,252 | 0.91% | 981 | 1 | City |
| St. Clair | 7 | 699 | 741 | -1.13% | 1,077 | 1 | City |
| Good Thunder | 8 | 530 | 558 | -1.12% | 845 | 1 | City |
| Amboy | 9 | 500 | 537 | -1.38% | 1,603 | 0 | City |
| Vernon Center | 10 | 311 | 329 | -1.27% | 636 | 0 | City |
| Skyline | 11 | 281 | 291 | -0.71% | 1,434 | 0 | City |
| Pemberton | 12 | 216 | 231 | -1.37% | 1,149 | 0 | City |
Mankato is the largest city in Blue Earth County, with a population of 46,917.
Pemberton is the smallest city in Blue Earth County, with a population of 216.
There are 12 cities in Blue Earth County, Minnesota.