- Obstetricians & Gynecologists, Ottawa - Ob-Gyn Doctors, Physicians & Surgeons (Obstetrics & Gynecology)
- Office Supplies, Equipment & Office Furniture Stores, Ottawa
- Oil Change & Lubrication, Ottawa - Auto Oil & Quick Lube
- Oil Industry & Oil Field Equipment & Services, Ottawa - Oil Companies
- Ophthalmologists, Ottawa - Eye Doctors, Physicians & Surgeons (Ophthalmology)
- Optical Stores - Eyeglasses, Lenses & Sunglasses, Ottawa
- Opticians, Ottawa
- Optometrists, Ottawa - Eye Doctors, Physicians & Surgeons (Optometry)
- Oral Surgeon, Ottawa - Dentists - Oral & Maxillofacial Surgeons
|
- Ornamental Greenhouses, Ottawa
- Ornamental Nursery, Ottawa
- Ornamental Nursery Products, Ottawa
- Ornamental Nursery Services, Ottawa
- Orthodontist, Ottawa - Teeth Straightening, Invisalign & Dental Braces
- Other Building Materials & Supplies, Ottawa
- Other Lodging, Ottawa
- Outdoor Furniture & Patio Furniture, Ottawa - Garden Furniture Stores
- Oxygen & Respiratory Equipment & Supplies, Ottawa - Oxygen Concentrator, Tank, Machine, etc
|