Harry Oldroyd to Charles Sidney Oliver - 1911 Census household returns
- Harry Oldroyd to James Oldroyd
- James Oldroyd to John Henry Oldroyd
- John Henry Oldroyd to Lewis Oldroyd
- Lilias Oldroyd to Robert Smith Oldroyd
- Roland Oldroyd to Tom Oldroyd
- Tom Oldroyd to William Martin Oldroyd
- William Peace Oldroyd to Elizabeth Jane Olds
- Emily Jane Olds to Joseph Olds
- Joseph G Olds to William Henry Olds
- William James Olds to John Joseph Oleary
- Joseph Oleary to Andrea Olesen
- M A Olesen to George T Olford
- Herbert Olford to Edmund Louis Oliff
- Elizabeth Oliff to Robert Dunlop Oliphans
- Alfred Oliphant to Grainger Oliphant
- Grainger Oliphant to Joseph Oliphant
- Joseph Oliphant to Tom Oliphant
- Walter Oliphant to George Olivant
- George Olivant to William Olivant
- William Henry Olivant to Charles Olive
- Charles Olive to Enida Higgins Olive
- Ernest Charles Olive to Henry Olive
- Henry Olive to John Olive
- John Olive to Margaret Ann Olive
- Maria Olive to Samuel Olive
- Sarah Olive to William Olive
- William Olive to Harry Oliven
- Fanny Olivenboum to Agnes Oliver
- Agnes Ellen Oliver to Albert Oliver
- Albert Oliver to Alexander Oliver
- Alexander Edward Oliver to Alfred Oliver
- Alfred Oliver to Alfred George Oliver
- Alfred George Oliver to Alice Oliver
- Alice Oliver to Andrew Oliver
- Andrew Oliver to Annie Oliver
- Annie Oliver to Arthur Oliver
- Arthur Oliver to Arthur Oliver
- Arthur Oliver to Arthur John Oliver
- Arthur John Oliver to Benjamin Oliver
- Benjamin Oliver to Benjamin Oliver
- C H M Oliver to Charles Oliver
- Charles Oliver to Charles Oliver
- Charles Oliver to Charles Oliver
- Charles Oliver to Charles Edward Oliver
- Charles Edward Oliver to Charles Sidney Oliver