Cities
- O'Brien
- O'Hanly
- O'Leary
- Oak Bay
- Oak Bay
- Oak Bay
- Oak Bluff
- Oak Haven
- Oak Lake
- Oak Orchard
- Oak Point
- Oak River
- Oakbank
- Oakburn
- Oakdale
- Oakdale
- Oakland
- Oakland
- Oakview
- Oakview Beach
- Oakville
- Oakville
- Oakwood
- Oba
- Oban
- Obaska
- Obed
- Obedjiwan
- Obiduan
- Ocean Falls
- Ochiltree
- Ochre River
- Oconnor
- Oconto
- Odanah
- Odanak
- Oderin
- Odessa
- Odessa
- Ogden
- Ogema
- Ogilvie
- Ogoki
- Ohaton
- Ohsawa
- Ohsweken
- Oil City
- Oil Springs
- Oka
- Okanagan
- Okanagan Centre
- Okanagan Falls
- Okanagan Landing
- Okanagan Mission
- Okanagan-Similkam
- Okanagan-Similkameen
- Okla
- Okotoks
- Olalla
- Old Chelsea
- Old Crow
- Old Factory River
- Old Fort
- Old Fort Bay
- Old Hogem
- Old Montreal
- Old Perlican
- Old Post
- Old Wives
- Oldcastle
- Olds
- Oleary
- Olha
- Olinda
- Oliphant
- Oliver
- Oliver Paipoonge
- Omemee
- Omerville
- Ompah
- Onanole
- Onaping
- Onaping Falls
- One Hundred Fifty Mile House
- One Hundred Mile House
- Onefour
- Oneida
- Onion Lake
- Onoway
- Oona River
- Ootischenia
- Ootsa Lake
- Opal
- Opasatika
- Opaskwayak
- Opasquia
- Open Hall
- Ophir
- Opishing Lake
- Orangedale
- Orangeville
- Ordale
- Orford
- Orford Twp
- Orient Bay
- Orillia
- Orillia Township
- Orion
- Orkney
- Orkney Beach
- Orland
- Orleans
- Ormiston
- Ormond
- Ormsby
- Ormstown
- Oro
- Oro Medonte
- Oro Station
- Oro-Medonte
- Oromocto
- Oromocto Nb
- Orono
- Orr Lake
- Orrville
- Orton
- Orwell
- Osaca
- Osage
- Osborne
- Osceola
- Osgoode
- Oshawa
- Oskelaneo
- Osland
- Osler
- Osnabruck Centre
- Osnaburgh House
- Osoyoos
- Oswego Park
- Otis
- Otonabee Twp
- Otonabee-South Monaghan
- Ottawa
- Otter
- Otter
- Otter Creek
- Otter Lake
- Otter Lake
- Otterburn Park
- Otterburn-Park
- Otterburne
- Otterville
- Ouellette
- Ouest de l'ile - Montreal
- Ouiatchouan
- Ouimet
- Oungah
- Oungre
- Outaouais
- Outlet
- Outlook
- Outlook
- Outram Station
- Ouvry
- Overton
- Owen Sound
- Owl River
- Owlseye
- Oxbow
- Oxbow Lake
- Oxdrift
- Oxenden
- Oxford
- Oxford Centre
- Oxford House
- Oxford Junction
- Oxford Mills
- Oxford Station
- Oxley
- Oxley Beach
- Oxtongue Lake
- Oyama
- Oyen
- Oyster Bay
Postal codes
- J0H2E0
- J0P1W0
- J0L2J0
- G0S1H0
- K0K3E0
- J0J2C0
- J5R5W6
- J7V0M1
- G0R3Y0
- J6E8E2
- G0L2N0
- J0R1T0
- J0G1K0
- S0K3J0
- J0E1V0
- J0B1M0
- H3X3C8
- N4K5N7
- N0R1J0
- T0M2G0
- L0G1J0
- J3H6G8
- J8L1R4
- J6N2C4
- G6Z2L2
- S0G3S0
- V0H1B0
- L0K1E0
- K0A2M0
- M4T1G6
- H8S1T6
- J6E3Z1
- H9H2W5
- J0R1R0
- J3L2L9
- H1B5A9
- H3R1K2
- G1V4J7
- G0C2J0
- B4B1Z7
- G3N0N5
- N0A1H0
- N2K1S5
- P0J1P0
- L1N3W2
- L5N3R9
- M3M4M5
- K1P1J1
- K0A2P0
- M4N1K1
- J5Z4K5
- J0T2C0
- J0T1M0
- J0A1L0
- J2A3V8
- J0L1N0
- J0L2R0
- J7N2M8
- C0A1M0
- G7G3N7
- G0R2N0
- H1A0A1
- G0X3J0
- G1V3X5
- H2J2N1
- T0H1Z0
- S0H0X0
- T5A0A7
- N0P2L0
- S0M0H0
- M5R2T6
- T0L0H0
- M9M1A2
- N0N1T0
- M9P1C4
- N0G1A0
- V0E1M9
- T0A2E0
- M5P2N7
- T0K1W0
- V3C2T7
- N0L1B0
- V8L5T9
- T5K0Z1
- R0L1M0
- N0A1P0
- V3A6H8
- P0L1C0
- V5V3C2
- P0M1L0
- R0G0Z0
- T0L1R0
- m1k2e3
- L5R0B3
- L4Y2C6
- K0H1G0
- L6y0y4
- K4M1B4
- M2N7L4
- K8N5W6