O
- (Cape Winelands District Municipality) Onder-Papegaaiberg
- (Cape Winelands District Municipality) Orangezig
- (Central Karoo District Municipality) Ouland
- (Overberg District Municipality) Ouplass
- (Eden District Municipality) Outeniekwa
- (City of Cape Town) Oakdale
- (City of Cape Town) Oaklands
- (City of Cape Town) Oatlands
- (City of Cape Town) Ocean View
- (Cape Winelands District Municipality) Olkersia
- (Overberg District Municipality) Oukraal
- (Overberg District Municipality) Onrus
- (Cape Winelands District Municipality) Ons Rust
- (Cape Winelands District Municipality) Op-die-Berg
- (Overberg District Municipality) Ouda Brug
- (Overberg District Municipality) Oude Bosch
- (City of Cape Town) Oudekraal
- (West Coast District Municipality) Oudekraalfontein
- (City of Cape Town) Oude Raapkraal
- (Cape Winelands District Municipality) Oude Scheur
- (Overberg District Municipality) Oukraal