| Ochsendorf | <703> |
| Oden | <958> |
| Oesfeld | <162> |
| Oesterreich | <736b> |
| Öhlmann (Ölmann) | <511>, <704> - <705> |
| Oldenhausen | <479a> |
| Opitz | <932> |
| Oppermann | <60>, <160>, <181>, <532>, <614>, <707> - <709a>, <790>, <1075a> |
| Orth | <778> |
| Ostburgen | <512> |
| Ostedt | <857> |
| Osterloh | <90a>, <292>, <343a>, <475>, <600>, <605>, <707>, <710> - <736a>, <1008>, |
| Osterwohl | <737> |
| Othmer | <111> |
| Otte | <306>, <433>, <738> - <741> |