- Old Farm Acres
- Old Ford
- Old Fort
- Old Gilreath
- Old Grove Mobile Home Park
- Old Hollow Estates
- Old Hundred
- Old Mill
- Old Sneedsboro
- Old Sparta
- Old Spring Hope
- Old Town
- Old Town
- Old Town Harbor
- Old Trap
- Old Weeksville
- Olde Farm
- Olde Providence
- Olds
- Oldtown
- Olin
- Olive Branch
- Olive Grove
- Olive Hill
- Olive Hill
- Oliver
- Olivers
- Olivers Crossroads
- Olivers Crossroads
- Olivet