Companies catalogue
- O'Brien Group Arena, Docklands
- O'Briens Mechanical, Caboolture
- O'Byrne Motors, Redland Bay
- O'Rourke Monuments, Sunbury
- O'loughlin Susan DR., Armidale
- O-Bento, Docklands
- O-Bento, Melbourne
- O-Bento Docklands, Docklands
- OCLC (Australia and New Zealand), Melbourne
- OCTEC Employment Service, Armidale
- OKAMI Japanese Restaurant - Brunswick, Brunswick
- OKAMI Japanese Restaurant - Footscray, Footscray
- ON Track 4WD Centre, Slacks Creek
- OSHClub Pascoe Vale, Pascoe Vale
- OTI Racing & Bloodstock, Docklands
- OZI INDIAN TV CHANNEL, Rocklea
- Oak Park Acupuncture and Chinese Medicine Clinic, Oak Park
- Oak Park Kindergarten, Oak Park
- Oak Tree Retirement Village Taylor St Armidale, Armidale
- Oaklands Hunt Club, Greenvale
- Oaklands Hunt Club Inc., Greenvale
- Oasis on Marsh, Armidale
- Ochre Plumbing and Gasfitting, Altona North
- Off the Pier, Williamstown
- Office Space Design, Melbourne
- Office of Public Prosecutions, Melbourne
- OfficeOurs, Yarraville
- Official Neighbours Tours, Melbourne
- Oil Depot, Yeerongpilly
- Oko Oko, Carlton
- Old Chilli B&B, Daylesford
- Old Geology Theatre 1, Parkville
- Old Melbourne Gaol, Melbourne
- Old Melburnians Hockey Club, Port Melbourne
- Old Mill Brasserie Armidale Ex services Club, Armidale
- Old and Butchered, Brisbane City
- Olive Media, Ascot
- Olive Tree Hotel, Sunbury
- Oliver Lumley & Associates Management & Accounting Services, Melton
- Oliver's Motorcycles, Moorooka
- Ollie's Place, Melton West
- Ollies Chicken, Melton
- Ollies Chicken Hillside, Hillside
- Olympia Gymnasium, South Melbourne
- Olympic Taekwondo Centre, Campbellfield
- Olympic Winter Institute of Australia, Docklands
- Omada Day Spa, Daylesford
- Omnibus Art Gallery, Ballan
- On Country Heritage and Consulting, North Melbourne
- Oncology Unit Armidale Hospital, Armidale
- Ondrik Larsen Lawyers, West Melbourne
- One Addiction, Lawnton
- One Of A Kind, Armidale
- One Stop Adventures, Melbourne
- One69 Main Street Cafe, Bacchus Marsh
- Only About Children Highpoint, Maribyrnong
- Onsite Pet Care Services, Seddon
- Oomph Osteopathy, Armidale
- Oorala Aboriginal Centre, Armidale
- Open Door Baptists Church, Brookfield
- Open for Life - Eiran Trethowan - Career, Life & Relationship Coaching, Reiki Therapist Counsellor Facilitator., Essendon
- OpenText Australia, Melbourne
- Oporto - Melbourne Airport QANTAS, Melbourne
- Opteon, Werribee
- Opteon, Docklands
- Oracle Insurance Solutions, Armidale
- Orange Hire, Tullamarine
- Orbit Cleaning Services Australia, North Melbourne
- Orchard Green, Melton South
- OreKinetics, Carole Park
- Organ Pipes National Park, Keilor North
- Orient Express Derrimut, Derrimut
- Origo BPO, Melbourne
- Ormond Statue, Melbourne
- Orthomedico Australia, Eagle Farm
- Otway Discovery Great Ocean Road Tours, Melbourne
- Our Lady Ta' Pinu Shrine, Merrimu
- Our Vet Melton, Melton
- Out N About Mechanical, Caboolture
- Outcome.Life, Carlton
- Outcross, Armidale
- Outotec, West End
- Outside The Square Accessories & Imaging, Broadmeadows
- Overnewton Anglican College, Taylors Lakes
- Overnewton Anglican Community College - Keilor Campus, Keilor
- Overnewton Castle Wedding Venue Melbourne, Keilor
- Owen Dixon Chambers East, Melbourne
- Oxley Wild Rivers NP - Dangar Falls picnic area, Dangarsleigh
- Oxley Wild Rivers National Park, Hillgrove
- Oyster Bar & Grill, Southbank
- Oz Aquarium Distributors, Altona North
- Oz Experience, Melbourne
- Oz Family Day Care, Kensington
- Oz Kebabs, Sunbury
- Oz Soda Blasting, Werribee
- Ozanam House, North Melbourne
- Ozmoto Motorcycle Hire, Brisbane
- Ozstyle Kitchens, Armidale
- Ozzy Dog Care, Bacchus Marsh
- onepointsix, North Melbourne