__TOC__
On
|- class="vcard" | class="fn org" | Onchan | class="adr" | Isle of Man | class="note" | | class="note" | |- class="vcard" | class="fn org" | Onecote | class="adr" | Staffordshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Onehouse | class="adr" | Suffolk | class="note" | | class="note" | |- class="vcard" | class="fn org" | Onen | class="adr" | Sir Fynwy (Monmouthshire) | class="note" | | class="note" | |- class="vcard" | class="fn org" | Onesacre | class="adr" | Sheffield | class="note" | | class="note" | |- class="vcard" | class="fn org" | Onibury | class="adr" | Shropshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Onich | class="adr" | Highland | class="note" | | class="note" | |- class="vcard" | class="fn org" | Onllwyn | class="adr" | Castellnedd Phort Talbot (Neath Port Talbot) | class="note" | | class="note" | |- class="vcard" | class="fn org" | Onneley | class="adr" | Staffordshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Onslow Village | class="adr" | Surrey | class="note" | | class="note" | |- class="vcard" | class="fn org" | Onthank | class="adr" | East Ayrshire | class="note" | | class="note" |
Op
|- class="vcard" | class="fn org" | Openshaw | class="adr" | Manchester | class="note" | | class="note" | |- class="vcard" | class="fn org" | Openwoodgate | class="adr" | Derbyshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Opinan | class="adr" | Highland | class="note" | | class="note" |
Or
|- class="vcard" | class="fn org" | Oran | class="adr" | Moray | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orange Row | class="adr" | Norfolk | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orasaigh / Orinsay | class="adr" | Western Isles | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orbiston | class="adr" | North Lanarkshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orby | class="adr" | Lincolnshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orchard Hill | class="adr" | Devon | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orchard Park | class="adr" | Cambridgeshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orchard Leigh | class="adr" | Buckinghamshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orchard Portman | class="adr" | Somerset | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orcheston | class="adr" | Wiltshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orcop | class="adr" | Herefordshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orcop Hill | class="adr" | Herefordshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ord (Ross and Cromarty) | class="adr" | Highland | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ord (Skye) | class="adr" | Highland | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ordale | class="adr" | Shetland Islands | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ordhead | class="adr" | Aberdeenshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ordie | class="adr" | Aberdeenshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ordiquhill | class="adr" | Aberdeenshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ordley | class="adr" | Northumberland | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ord Mill | class="adr" | Aberdeenshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ordsall | class="adr" | Nottinghamshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ordsall | class="adr" | Salford | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ore | class="adr" | East Sussex | class="note" | | class="note" | |- class="vcard" | class="fn org" | Oreston | class="adr" | Devon | class="note" | | class="note" | |- class="vcard" | class="fn org" | Oreton | class="adr" | Shropshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orfasay | class="adr" | Shetland Islands | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orford | class="adr" | Cheshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orford | class="adr" | Suffolk | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orford Ness | class="adr" | Suffolk | class="note" | | class="note" | |- class="vcard" | class="fn org" | Organford | class="adr" | Dorset | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orgreave | class="adr" | Sheffield | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orgreave | class="adr" | Staffordshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Oridge Street | class="adr" | Gloucestershire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orkney | class="adr" | Orkney Islands | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orlandon | class="adr" | Sir Benfro (Pembrokeshire) | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orleton | class="adr" | Herefordshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orleton | class="adr" | Worcestershire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orleton Common | class="adr" | Herefordshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orlingbury | class="adr" | Northamptonshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormacleit | class="adr" | Western Isles | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormal | class="adr" | Shetland Islands | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormathwaite | class="adr" | Cumbria | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormesby | class="adr" | Redcar and Cleveland | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormesby St Margaret | class="adr" | Norfolk | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormesby St Michael | class="adr" | Norfolk | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormiscaig | class="adr" | Highland | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormiston | class="adr" | East Lothian | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormiston | class="adr" | Scottish Borders | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormsaigbeg | class="adr" | Highland | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormsaigmore | class="adr" | Highland | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormsary | class="adr" | Argyll and Bute | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormsgill | class="adr" | Cumbria | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ormskirk | class="adr" | Lancashire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ornish Island | class="adr" | Western Isles | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ornsay | class="adr" | Highland | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ornsby Hill | class="adr" | Durham | class="note" | | class="note" | |- class="vcard" | class="fn org" | Oronsay | class="adr" | Argyll and Bute | class="note" | | class="note" | |- class="vcard" | class="fn org" | Oronsay (Loch Bracadale) | class="adr" | Highland | class="note" | | class="note" | |- class="vcard" | class="fn org" | Oronsay (Loch Sunart) | class="adr" | Highland | class="note" | | class="note" | |- class="vcard" | class="fn org" | Oronsay (Outer Hebrides) | class="adr" | Western Isles | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orosay (South Uist) | class="adr" | Western Isles | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orosay (Barra) | class="adr" | Western Isles | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orpington | class="adr" | Bromley | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orrell | class="adr" | Sefton | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orrell | class="adr" | Wigan | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orrell Post | class="adr" | Wigan | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orrisdale | class="adr" | Isle of Man | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orrock | class="adr" | Fife | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orsay | class="adr" | Argyll and Bute | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orsett | class="adr" | Essex | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orsett Heath | class="adr" | Essex | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orslow | class="adr" | Staffordshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orston | class="adr" | Nottinghamshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orthwaite | class="adr" | Cumbria | class="note" | | class="note" | |- class="vcard" | class="fn org" | Ortner | class="adr" | Lancashire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton | class="adr" | Cumbria | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton | class="adr" | Moray | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton | class="adr" | Northamptonshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton | class="adr" | Staffordshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton Brimbles | class="adr" | Cambridgeshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton Goldhay | class="adr" | Cambridgeshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton Longueville | class="adr" | Cambridgeshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton Malborne | class="adr" | Cambridgeshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton on the Hill | class="adr" | Leicestershire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton Rigg | class="adr" | Cumbria | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton Southgate | class="adr" | Cambridgeshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton Waterville | class="adr" | Cambridgeshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orton Wistow | class="adr" | Cambridgeshire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Orwell | class="adr" | Cambridgeshire | class="note" | | class="note" |
Os
|- class="vcard" | class="fn org" | Osbaldeston | class="adr" | Lancashire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Osbaldeston Green | class="adr" | Lancashire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Osbaldwick | class="adr" | York | class="note" | | class="note" | |- class="vcard" | class="fn org" | Osbaston | class="adr" | Leicestershire | class="note" | | class="note" | |- class="vcard" | class="fn org" | Osbaston (Telford) | class="adr" | Shropshire