601 results
| Olivier | 1834 |
| Opperman | 574 |
| Osman | 510 |
| Otto | 489 |
| Omar | 476 |
| Oberholzer | 451 |
| Oliver | 405 |
| October | 315 |
| Oliphant | 303 |
| Owen | 205 |
| O'connor | 170 |
| Osborne | 168 |
| Oliveira | 154 |
| O'brien | 151 |
| Ogle | 138 |
| O'reilly | 113 |
| Olsen | 93 |
| O'neill | 89 |
| O'connell | 81 |
| Overmeyer | 55 |
| Oakes | 53 |
| Ogilvie | 52 |
| Ohlson | 50 |
| Osborn | 47 |
| O'donoghue | 46 |
| Orr | 43 |
| Ochse | 39 |
| Owens | 39 |
| Orton | 38 |
| Oldfield | 38 |
| Oates | 38 |
| Olga | 37 |
| O'neil | 37 |
| Orchard | 34 |
| Opie | 32 |
| Oakley | 31 |
| O'kelly | 31 |
| Orpen | 30 |
| Orgill | 29 |
| O'callaghan | 29 |
| Olive | 28 |
| O'kennedy | 28 |
| Office | 27 |
| Oertel | 27 |
| Omara | 27 |
| Obermeyer | 27 |
| O'grady | 27 |
| O'malley | 27 |
| Oppelt | 26 |
| Obed | 25 |
| Oswald | 25 |
| O'donovan | 25 |
| O'shea | 25 |
| Openshaw | 24 |
| O'sullivan | 24 |
| Olver | 23 |
| Ord | 22 |
| Orange | 22 |
| Ortell | 21 |
| Oppel | 21 |
| Obi | 21 |
| Oxley | 21 |
| Oldridge | 20 |
| Oostendorp | 20 |
| Osmond | 20 |
| Orme | 20 |
| Odgers | 19 |
| Osler | 19 |
| Olds | 19 |
| Olsson | 19 |
| O'leary | 19 |
| Oeschger | 18 |
| Ori | 18 |
| Otten | 18 |
| Ogden | 18 |