- Orthomed
- Ontario Science Centre
- Omaze
- Onnit
- Olympus
- Ole Henriksen
- One Stop Parking
- Olight CA
- Oldspaghettifactory
- Officedepot
- Ordiservice
- Ollyshoes
- Orb Clothing
- Ovate
- Oster Canada
- Origami Owl CA
- Open A Party
- Ontariobeerkegs
- Oh Canada Eh
- Oakley Canada
- Optimalprint Canada
- Office Depot & OfficeMax
- Olay
- OneTravel
- Origin
- Old Navy Canada
- Ontario Parks
- Origins Canada
- Onegoodturn
- Onlinegolfballs
- Ontariophonecards
- Oxygenplus
- Onespotallergy
- Organickidz
- Omiyage
- Oldspice
- Oya Costumes CA
- Outfitters ca
- Origin PC
- Oral B
- Opa
- Old Navy
- Oberlo Canadas
- oralb
- OtterBox
- Olivers Labels
- Orbitz
- Olive Garden
- OrthoCanada
- Oneplus
- Opentip
- Oakley Si
- Otel.com
- Oriental Trading
- Opposuits
- Outback Steakhouse
- Orabel
- OneClass
- Outdoors Oriented
- Overstock.com
- Optics Planet
- Online Labels
- Origins
- Orchard
- Oakley
- Otticanet
- OneHanesPlace
- Omaha Steaks
- OshKosh B'gosh
- Onlineshoes
- Orvis
