dna next to a surname below indicates it has been registered with the DNA linking service
and the researcher is keen to find bearers of the same surname to join a DNA project.
ons next to a user below means the user has registered a one-name study of a surname
with the Guild of One-Name Studies.
| Surname | Timeframe | Place | Researcher |
|---|---|---|---|
| OAKLEY | Any | Any | Christine Norris |
| OCKENDEN | 18C | Oxford | Margaret Dixon |
| ODDINGTON | 1600-1800 | Any | Mick Cooper |
| OLDACRE | Any | Any | Colin Wills |
| OLDS | 1700 - 1900 | Banbury, Adderbury | Doreen Olds |
| OLIVER | >1600 | AllStonesfield, Finstock, Fawler, Glympton, Spelsbury, Woodstock, All | Shane Bywaters |
| OLIVER | <1680 | Launton | Rebecca Chapman |
| OLIVER | <1900 | Stonesfield | Neil Thaler |
| OLLENBUTTEL | Any | Headington | Patricia Murphy |
| ONION | 1820 | Yelford | Chris Etheridge |
| ONION | 1750 - 1820 | Witney | Chris Etheridge |
| ORCHARD | Any | Any | Jennifer Tinson |
| ORDWAY | 1760 | Deddington | Donna Lonon |
| ORGAN | Any | Cowley | Jill Muir |
| ORPWOOD | >1721 | Bampton | Linda Dutton |
| ORPWOOD | Any | Any | Graham Orpwood |
| ORPWOOD | <1850 | Bampton | Margaret Forbes |
| ORPWOOD | 18c | Abingdon | Chris Wake |
| ORPWOOD | <1775 | Bampton | Pauline Kennedy |
| ORSBORN | <1860 | Ambrosden, Banbury, Hook Norton, Southam, Leamington | G |
| ORSBOURN | Any | Chipping Norton | Pat Armer |
| OSBORN | >1700s | Chiselhampton; Stadhampton | Jemma Hayward |
| OSBORNE | Any | Any | Deborah Osborne Dunmall |
| OSBORNE | <1930 | Oxford | D Peasey |
| OSGATHORP | Any | Any | Ron Osgathorpe |
| OSGATHORPE | Any | Any | Ron Osgathorpe |
| OSMAN | 1840 | Oxford | Dave Horn |
| OSMAN | >1840 | Oxford | Ian Mullan |
| OSMOND | 19C | Bicester | Gail Stevens |
| OVENALL | 1700-1800 | Cassington, Combe | Gary Ovenell |
| OVENDEN | Any | Garsington, Headington, Cowley | Hilary |
| OVENDEN | All | Garsington | Martyn Payne |
| OVENELL | 1700-1800 | Cassington, Combe | Gary Ovenell |
| OVERALL | Any | Any | Roy Overall |
| OVERNELL | 1700-1800 | Cassington, Combe | Gary Ovenell |
| OWEN | >1780 | Chipping Norton | Dafde |
| OWEN | 1847-1893 | Claydon | Rosemary Probert |
| OWEN | Any | Chipping Norton | Christopher Reynolds Betteridge |
| OXLADE | Any | Any | Susan M. Rogers |
| OXLADE | Any | Any | Margaret East |