Companies catalogue
- OATC, Sudbury
- OATC, Mississauga
- OATC Oakville, Oakville
- OE Banquet & Conference Centre, Oakville
- OM Sanctuary, Burlington
- OMHRA, Guelph
- OPSEU Local 656, Sudbury
- ORIGINAL MONSTER BUDS, Sudbury
- OUAC, Guelph
- OVC Companion Animal Hosp, Guelph
- Oakville, Oakville
- Oakville After School Care, Oakville
- Oakville Airport Taxi, Oakville
- Oakville Art Society, Oakville
- Oakville Arts Studio Inc, Oakville
- Oakville Blueprinting, Oakville
- Oakville Gymnastics Club, Oakville
- Oakville Lawn Bowling Club, Oakville
- Oakville Power Boat Club, Oakville
- Oakville Sailing Squadron, Oakville
- Oakville Soccer Club - Field #3, Oakville
- Objectivity, Sudbury
- Old Fashioned Deli, Guelph
- Old King Bistro, Kitchener
- Olde Ukrainian Club, Sudbury
- Olive Tree, Guelph
- Oliver Centre, Edmonton
- Olivier K Dr, Sudbury
- OnSite Services Ltd, Sudbury
- Onaping Falls Clerk's Dept, Sudbury
- Onaping Falls Golden Age Club, Onaping
- Onaping Falls Lions, Sudbury
- Onaping Falls Medical Centre, Sudbury
- Onaping Falls Nordics Ski Club, Sudbury, Unorganized, North Part
- Onaping Golf & Beach Club, Onaping
- Onaping Golf & Beach Club, Onaping
- Ont Sheet Metal Workers Training Ctr The, Oakville
- Ontario Addiction Treatment Centres, Brampton
- Ontario AgriCentre, Guelph
- Ontario Apprenticeship & Trade, Mississauga
- Ontario Association Of Veterinary Technicians, Guelph
- Ontario Au Travail, Grand Sudbury
- Ontario Beekeepers' Association, Milton
- Ontario Breast Screening, Sudbury
- Ontario Breast Screening Program, Sudbury
- Ontario Community & Social Svc, Sudbury
- Ontario Driver-Vehicle Licence, Sudbury
- Ontario Drivers & Vehicles Ofc, Sudbury
- Ontario Duct Cleaning, Oakville
- Ontario English Catholic Teacher Association, Guelph
- Ontario English Catholic Teachers Association Waterloo Unit, Waterloo
- Ontario Environment & Energy, Sudbury
- Ontario Golf Superintendents Association, Guelph
- Ontario Greffe Des Affaires, Sudbury
- Ontario Hockey Association, Cambridge
- Ontario Hot Air Balloon Rides, Mississauga
- Ontario Hot Mix Producers Association, Mississauga
- Ontario Land Registry Offices, Sudbury
- Ontario Library Service - North, Sudbury
- Ontario March Of Dimes, Sudbury
- Ontario March of Dimes, Sudbury
- Ontario Masonry Training Centre, Mississauga
- Ontario Milk Transport Association, Guelph
- Ontario Northern Regional Ofc, Sudbury
- Ontario One Call, Guelph
- Ontario Probation & Parole, Sudbury
- Ontario Professional Foresters, Halton Hills
- Ontario Provincial Police, Sudbury
- Ontario Recreation Vehicle Dealers Association, Hamilton
- Ontario Regional Cancer Centre, Sudbury
- Ontario SPCA, Orangeville
- Ontario Sante-Ministere, Sudbury
- Ontario School Counsellors' Assoc, Erin
- Ontario Searching & Info Svc, Sudbury
- Ontario Solliciteur General, Sudbury
- Ontario Veterinary College, Guelph
- Ontario Veterinary Medical Association, Milton
- Opa's Kitchen, Guelph
- Operation Rednose Laurent, Sudbury
- Optical in Real Canadian Superstore, Sudbury
- Optique Girard Optical, Sudbury
- Oraclepoll Research, Sudbury
- Orange Hall, Guelph
- Orangeville Badminton Club, Orangeville
- Orangeville Concert Association, Orangeville
- Orangeville Minor Baseball Association, Orangeville
- Orangeville Opera House, Orangeville
- Orchard Park Office Centre, Guelph
- Organic Bodies Pilates Yoga, Sudbury
- Orpheus Music Management, Sudbury
- Orthotic Centre The, Sudbury
- Osteopathy by Colleen, Guelph
- Ottewell Daycare & After School Care, Edmonton
- Outdoor Art & Science School, Guelph
- Outotec Canada Ltd., Sudbury
- OvertheAtlantic, Sudbury
- Oxford Child Development Centre, Edmonton
- Oxford Child Development Centre - Lynnwood (OSC), Edmonton
- Oxford Child Development Centre - Main Daycare Centre, Edmonton
- ontariocolleges.ca, Guelph