Cities
- Oxford
- Oldham
- Oldmeldrum
- Oldbury
- Ossett
- Oadby
- Oakham
- Oban
- Ockley
- Odiham
- Okehampton
- Old Basford
- Old Basing
- Old Dalby
- Ollerton
- Olney
- Omagh
- Onecote
- Ongar
- Orkney
- Ormskirk
- Orpington
- Orrell
- Osgodby
- Oswestry
- Otley
- Ottery St Mary
- Oulton Broad
- Over
- Overton
- Oxon
- Oxted
- Oxton
- Oundle
- Oversley Green
- Old Catton
- Old Trafford
- Olton
- Ovingdean
- Oakley Green
- Old Windsor
- Old Town
- Old Clee
- Oakley
- Old Stratford
- Outer Hebrides
- Overtown
- Orkney Islands
