7 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Decorah | 1 | 7,578 | 7,578 | 0% | 1,046 | 7.24 | City |
| Calmar | 2 | 1,073 | 1,132 | -1.11% | 955 | 1.12 | City |
| Ossian | 3 | 769 | 803 | -0.9% | 720 | 1.07 | City |
| Spillville | 4 | 363 | 385 | -1.09% | 827 | 0.44 | City |
| Fort Atkinson | 5 | 295 | 310 | -1.01% | 928 | 0.32 | City |
| Ridgeway | 6 | 257 | 276 | -1.53% | 340 | 0.76 | City |
| Castalia | 7 | 135 | 144 | -1.46% | 234 | 0.58 | City |
Decorah is the largest city in Winneshiek County, with a population of 7,578.
Castalia is the smallest city in Winneshiek County.
There are 7 cities in Winneshiek County, Iowa.