South West
O
- Oak, Broad, South West
- Oak, Broad, East Devon
- Oakfordbridge
- Oakhill, South West
- Oakhunger
- Oakland Park
- Oakle Street
- Oakley, Bournemouth Christchurch An
- Oakley, Dorset
- Oakridge
- Oaksey
- Oaksey Green
- Oakwood Bottom
- Oakwood Hill, South West
- Oare
- Oare Hill
- Oareford
- Oath
- Oathill
- Oborne
- Obridge
- Ockold End
- Odcombe
- Odd Down
- Oddway
- Odham
- Odstock
- Offwell
- Ogbeare
- Ogbeare Mill
- Ogbourne Maizey
- Ogdens
- Ogwell, East
- Ogwell, West
- Okeford Fitzpaine
- Okehampton
- Okeltor
- Okus
- Old Cardinham
- Old Cardinham Castle
- Old Cleeve
- Old Dilton
- Old Ditch
- Old Down, Somerset
- Old Down, South Gloucestershire
- Old Forge, South West
- Old Grimsby
- Old Hill, North Somerset
- Old Hollow
- Old Kea
- Old Mills
- Old Park, South West
- Old Passage
- Old Polapit Tamar
- Old Sarum
- Old Sodbury
- Old Town, Isles of Scilly
- Old Town, Somerset
- Old Wardour
- Old Way
- Oldborough
- Oldbury Court Estate
- Oldbury Naite
- Oldbury on the Hill
- Oldcroft
- Oldend
- Oldfield Park
- Oldford
- Oldland
- Oldland Common
- Oldmill
- Oldmixon
- Oldridge
- Oldway, Torbay
- Oldways End
- Oldwit
- Olveston
- Orange End
- Orchard Hill
- Orchard Portman
- Orchard, East
- Orchard, High
- Orchard, West
- Orchardleigh Park
- Orcheston
- Orcheston St. George
- Orcheston St. Mary
- Orepool
- Oreston
- Organford
- Orleigh Mills
- Osehill Green
- Osmington
- Ossington
- Othery
- Otterham
- Otterhampton
- Otterton
- Ottery St Mary
- Outer Hope
- Outlands, South West
- Outmarsh
- Outwick
- Outwood, Somerset
- Oval, The, South West
- Over, South Gloucestershire
- Over, Tewkesbury
- Over Compton
- Over Stowey
- Over Stratton
- Over Street
- Overbridge
- Overbury
- Overcombe
- Overhill Farm
- Overleigh, Somerset
- Overton, Somerset
- Overton, Stroud
- Overton Park
- Overtown, Stroud
- Overtown, Swindon
- Ower, South West
- Owley
- Owlpen
- Ownham
- Ox Mead, White
- Oxbridge, South West
- Oxenpill
- Oxenton
- Oxlynch
- Oxton, Teignbridge
- Ozleworth