- Inman
- Idylside
- Illinois City
- Imbs
- Ingraham
- Ivanhoe
- Illiopolis
- Indian Creek
- Indian Head Park
- Ingalls Park
- Ipava
- Indian Spring
- Island Lake
- Itasca
- Ivesdale
- Iowa Junction
- Indian Island
- Island Number 317
- Island Number 318
- Island Number 319
- Island Number 322
- Island Number 328
- Island Number 330
- Island Number 336 (historical)
- Iles
- Irwins Park
- Island Grove
- Island Grove
- Idlewood
- Illiana