11 cities
| City | County | 2026 Pop. ↓ |
|---|---|---|
| Iowa City | Johnson County | 77,608 |
| Indianola | Warren County | 16,514 |
| Independence | Buchanan County | 6,357 |
| Iowa Falls | Hardin County | 4,944 |
| Ida Grove | Ida County | 1,950 |
| Inwood | Lyon County | 980 |
| Ireton | Sioux County | 565 |
| Irwin | Shelby County | 320 |
| Ionia | Chickasaw County | 216 |
| Irvington | Humboldt County | 100 |
| Imogene | Fremont County | 36 |