| Interest Name | Parish/ Town | County | Period | No | Name | |
| Oakey | Attleborough | WAR | 1700-1950 | 160 | Mr & Mrs D Malbasa | d.malbasa@btinternet.com |
| Oakey | Attleborough | WAR | All | 163 | Mrs Kathleen O'Farrell | kathleenofarrell@btinternet.com |
| Oldham | Foleshill | WAR | All | 5 | Mrs R L Beebe | wind13@talktalk.net |
| Oliver | Arley | WAR | Pre 1830 | 71 | Mrs Sheila M Dunn | sheilaandjohndunn@tiscali.co.uk |
| Olner | Any | WAR | All | 9 | Ms Sandra Muis | muis@sympatico.ca |
| Onions | Oakengates | SAL | 1800+ | 253 | Mr William Boswell | wboswell@gotadsl.co.uk |
| Orme | Nuneaton | WAR | 1800's | 67 | Mr Moreton J Ensor | nelson@capecod.net |
| Orton | Bulkington | WAR | pre 1800 | 199 | Mrs Julia Hamilton Andrews | andrewsjulia@hotmail.com |
| Orton | Nuneaton | WAR | All | 19 | Mr David Robert Battlebury | d.battlebury@ntlworld.com |
| Orton | Mancetter | WAR | 19th Cent | 210 | Ms Janice Fairfield | familytree.janicefairfield@blueyonder.co.uk |
| Orton | Bedworth | WAR | 19th Cent | 210 | Ms Janice Fairfield | familytree.janicefairfield@blueyonder.co.uk |
| Orton | Atherstone / Nuneaton | WAR | All | 123 | Mr Garry Long | gazlong@ntlworld.com |
| Orton | Ansley | WAR | All | 46 | Mrs Wendy MacGregor | mercialoud@googlemail.com |
| Orton | Mancetter | WAR | 16th-19thC | 266 | Mr Tim Horton | tim@horton03.fsnet.co.uk |
| Orton | Atherstone | WAR | 18th-19thC | 266 | Mr Tim Horton | tim@horton03.fsnet.co.uk |
| Orton | Sibson / Ratcliffe Culey | LEI | 19thC | 266 | Mr Tim Horton | tim@horton03.fsnet.co.uk |
| Ozierbrook | Atherstone | WAR | 1800+ | 242 | Mrs Joan Keturah Randle | joan@jrandle.fsnet.co.uk |