- Oldfield
- Oldfield
- Oldfield
- Oldford
- Oldhill Wood
- Oldwood
- Oliver's Island
- Ollerton
- Once Brewed
- Onehouse
- Ongar
- Onley
- Orchard Leigh
- Orcop Hill
- Oreton
- Ormesby St Michael
- Orsett Heath
- Osbaldeston
- Osbaldwick
- Osbaston
- Oscroft
- Osgathorpe
- Osgodby
- Osprey Quay, Portland
- Ostend
- Osterley
- Oughterside
- Oulton
- Oulton
- Oulton Broad