Place
- Indian Creek, Illinois2
- Indian Head Park, Illinois2
- Ingalls Park, Illinois2
- Inverness, Illinois2
- Island Lake, Illinois2
- Itasca, Illinois2
- Justice, Illinois2
- Kenilworth, Illinois2
- Kildeer, Illinois2
- Knollwood, Illinois2
- La Grange Park, Illinois2
- La Grange, Illinois2
- Lake Barrington, Illinois2
- Lake Bluff, Illinois2
- Lake County, Illinois2
- Lake Forest, Illinois2
- Lake Zurich, Illinois2
- Lemont, Illinois2
- Libertyville, Illinois2
- Lincolnshire, Illinois2