Companies catalogue
- O K Egg Farm, Elmira
- O&B Canteen, Toronto
- O'Connor Electric, Kitchener
- O'Shanter Development Co Ltd, Toronto
- O.E Design & Build, Toronto
- OCHO, Toronto
- ODDSEOUL, Toronto
- OGTC - Ontario Group of Touring Companies, Toronto
- OLG Slots and Casinos Head Office, Toronto
- OMAS, Toronto
- OMERS Capital Markets, Toronto
- OMJ Mortgage Capital Inc., Markham
- ONE Restaurant, Toronto
- OPEN ROAD LEASING INC, Brampton
- OTC Toronto, Toronto
- Oak Grove Cheese Factory LTD, New Hamburg
- Oakham Cafe, Toronto
- Oakridge Capital, Toronto
- Oakville Hydro Electricity Distribution Inc., Oakville
- Oakwood Collegiate Institute, Toronto
- Oasis Capital, Markham
- Oksana Shoe Repair, Markham
- Oksana Shoe Repair, Vaughan
- Olascom Virtual Solutions, Toronto
- Old Bleu Café Eatery, Toronto
- Old Bread Mill, Richmond Hill
- Old Capital Hot Pot, Toronto
- Old Soul Carpentry Club, Toronto
- Olga's Espresso Bar, Toronto
- Oliver & Bonacini Café Grill, Toronto
- Olympia Steel Buildings of Canada, Markham
- Olympia Steel Buildings of Canada, Markham
- Omega Tours, Vaughan
- One Hour Cafeteria, Toronto
- One King West, Toronto
- One King West Hotel & Residence, Toronto
- One Queen Street East, Toronto
- One Source Inc., Toronto
- One Stop Ticket Shop, Toronto
- OneEleven, Toronto
- Ontario 1 Restoration Inc., Toronto
- Ontario Broiler Chicken Hatching Egg Producers Association, Guelph
- Ontario Business Central, Toronto
- Ontario Chamber of Commerce, Toronto
- Ontario Craft Brewers, Toronto
- Ontario Forklift Training, Mississauga
- Ontario Sewage Treatment Plant, Elora
- Ontario Spring Water Sake Company, Toronto
- Ontario Vehicle Inspection, Toronto
- Ontario Virtual School (Online Credit High School), Toronto
- Optimum Talent Mississauga, Mississauga
- Optus Capital, Toronto
- Orangeville Hydro Limited, Orangeville
- Orion, Toronto
- Orion Assessment Services, Toronto
- Ortega Jarvis, Toronto
- Osaka Sushi 大阪寿司多伦多, Toronto
- Osgoode Hall, Toronto
- Osgoode Hall Law School, Toronto
- Osgoode Hall Restaurant, Toronto
- Osgoode Professional Development, Toronto
- OshKosh B'gosh, Kitchener
- OshKosh B'gosh, Woodstock
- Osprey Capital Partners Inc., Toronto
- Ossington Chapel, Toronto
- Osso Electric Supplies, Cambridge
- Otaner Inc., Guelph
- Our Lady Of The Rosary, Toronto
- Our Lady Queen of Croatia Church, Toronto
- Our Lady Queen of the World Parish, Richmond Hill
- Our Lady of Good Counsel Catholic Church, Toronto
- Our Lady of Grace Separate School, Toronto
- Our Lady of Guadalupe Catholic School, Toronto
- Our Lady of Guadalupe Roman Catholic Church, Toronto
- Our Lady of Lebanon Parish, Toronto
- Our Lady of Lourdes, Toronto
- Our Lady of Lourdes School, Toronto
- Our Lady of Mount Carmel Catholic School, Toronto
- Our Lady of Mount Carmel Church, Toronto
- Our Lady of Peace Catholic School, Toronto
- Our Lady of Peace Church, Toronto
- Our Lady of Perpetual Help Church, Toronto
- Our Lady of Perpetual Help Separate School, Toronto
- Our Lady of Sorrows Catholic School, Toronto
- Our Lady of Sorrows Church, Toronto
- Our Lady of Victory Catholic School, Toronto
- Our Lady of Victory Church, Toronto
- Our Lady of Wisdom Separate School, Toronto
- Our Lady of the Airways Church, Mississauga
- Our Lady of the Assumption, Toronto
- Our Lady of the Assumption Catholic School, Toronto
- Our Lady of the Rosary Catholic Elementary School, Vaughan
- Out of This World Café, Toronto
- Ovchinnikov Vladislav Dr, Toronto
- Over Easy, Toronto
- Oxford College of Arts, Business, and Technology, Toronto
- Oxford College of Arts, Business, and Technology, Toronto
- Oxford Properties, Toronto
- Oxford TPS, Toronto
- Oxygen Research Inc, Toronto