- Norman (continued)
- Norquoy
- Norrell
- Norridge
- Norrie
- Norris
- North
- Northall
- Norton
- Norval
- Norwood
- Nosworthy
- Nother
- Nott
- Nottage
- Nottingham
- Novick
- Novis
- Nowlan
- Noyce
- Nuckley
- Nunn
- Nurden
- Nurrish
- Nutbeem
- Nute
- Nutley
- Nutt
- Nutter
- Nycholas
- Nye
- Nyren
- O'Brian
- O'Brien
- O'Bryon
- Eliza (1807 - after 1871)
- O'Callaghan
- O'Connell
- O'Connor
- O'Donaghue
- O'Donnell
- O'Donoghue
- O'Driscoll
- O'Grady
- O'Hagan
- O'Hare
- O'Kane
- O'Keefe
- Julia (1880 - circa 1977)
- O'Malley
- Anne (between 1869 and 1870 - )
- O'Mara
- O'Neil
- O'Neill
- O'Shaughnessy
- O'Shea
- O'Sullivan