- Old Cambridge
- Old City
- Old Cock
- Old Common
- Old Harbor
- Old Harry Rock
- Old Hill
- Old Kelick Rock
- Old Man
- Old Mouth North River
- Old North Ashburnham Station
- Old Oaken Bucket Homestead
- Old Quaker Meetinghouse
- Old Silver Beach
- Old Skunk
- Old Sow
- Old Spain
- Old Spirit Rock
- Old Sturbridge Village
- Old Town Landing
- Old Whale Rock
- Olde English Village
- Oldham Pines
- Oldham Village
- Onset
- Onset Island
- Onset Station
- Orange
- Orchard Hills Estates
- Orient Heights