7 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Williamsburg | 1 | 3,394 | 3,352 | 0.21% | 1,007 | 3 | City |
| Marengo | 2 | 2,403 | 2,438 | -0.25% | 1,136 | 2 | City |
| North English | 3 | 1,014 | 1,061 | -0.78% | 1,671 | 1 | City |
| Victor | 4 | 842 | 872 | -0.59% | 1,751 | 0 | City |
| Ladora | 5 | 220 | 229 | -0.45% | 746 | 0 | City |
| Parnell | 6 | 188 | 193 | -0.53% | 1,062 | 0 | City |
| Millersburg | 7 | 134 | 136 | 0% | 1,098 | 0 | City |
Williamsburg is the largest city in Iowa County, with a population of 3,394.
Millersburg is the smallest city in Iowa County, with a population of 134.
There are 7 cities in Iowa County, Iowa.