Places beginning with OR in Illinois, United States
- Orange
- Orangemans Hall
- Orange Prairie
- Orange, Township of
- Orange, Township of
- Orangeville
- Oran, Township of
- Ora, Township of
- Oraville
- Orchard, Township of
- Orchardville
- Oreana
- Oregon
- Oregon-Nashua, Township of
- Oregon, Township of
- Orel, Township of
- Orient
- Orio
- Orion
- Orion, Township of
- Orland Hills
- Orland Park
- Orland, Township of
- Orleans
- Ormonde
- Orvil, Township of