O
- O'Dell
- O'Reilly's Bridge
- Oak Bay
- Oakland
- Oak Orchard
- Oak Ridges
- Oak Valley
- Oakville
- Ocean Park
- Odanak 12
- Odena
- Odessa
- Ogden
- Ohamil 1
- Ohsweken
- Oja
- Ojibway
- Oka
- Okanagan 1
- Okanagan Centre
- Okanagan Falls
- Okanagan Landing
- Olalla
- Oldcastle
- Oldfield
- Old Glenridge
- Old Road Crossing
- Oliver
- Oliver
- Oliver Paipoonge
- Omagh
- Omemee
- Omerville
- Oneida 41
- Onondaga
- Ootischenia
- Orange Corners
- Orchard Grove
- Orchardside
- Orford
- Oriole Parkway
- Orléans-Club
- Orleans
- Ormond Beach
- Ormstown
- Oro-Medonte
- Oro Beach
- Oro Lea Beach
- Orono
- Oro Park
- Oro Station
- Orr Lake
- Orrville
- Orsainville
- Orton
- Orwell
- Osborne Corners
- Osgoode
- Oshawa
- Osnabruck Centre
- Osoyoos
- Osoyoos 1
- Osoyoos 3
- Ospringe
- Otonabee-South Monaghan
- Ottawa
- Otter
- Otterburn Park
- Otter Lake
- Otter Lake 2
- Oungah
- Oustic
- Outremont
- Ouvry
- Oxtongue Lake
- Oyama
- Ozanam
