Bedrift O - Nordstrand
- Oma AS
- Otco AS
- Office4u AS
- Oppdater AS
- Omsorgsteam AS
- Organica AS
- Orthobache AS
- Or64
- Or64
- Orv60b AS
- Omnipro AS
- Orkesterkollektivet
- Onetwo3 AS
- Obc AS
- October Atelier
- October Atelier
- Oma Ohnstad
- Ole Brørby
- Oliver Bellefine
- Oleksandr Sheptukha
- Omil Holding AS
- Opa Holding AS
- Onco Consulting AS
- Opptur Aktiv AS
- Ola Moen
- Oda Lyngås
- Ottar Julsrud
- Ottar Langseth
- Oslo Pensjonistparti
- Omano Invest AS
- Oslo Anleggsgartner AS
- Oda Invest AS
- Orange Gaming AS
- Oppegård Seilforening
- Oslos Skøytevenner
- Oslo Møbelsnekkeri AS
- Ocl Holding AS
- Ostvoll Invest AS
- Obersten Barnehage
- Oban Invest AS
- Origo Invest AS
- Olberg Transport AS
- Obersten Invest AS
- Oberst Elektro AS
- Oslo Liftbil AS
- Oslohus Drift AS
- Oslohus Utvikling AS
- Oslohus Eiendom AS
- Omar Taxi
- Oslo Rådgivning AS
- Ola Akselberg
- Oslo Accounting AS
- Oslo Guideforening
- Oslo Guideforening
- One Team AS
- Outline Ventures AS
- Onedev Magnussen
- Ovis Invest AS
- Ond Spiral AS
- Onedev Consultancy AS
- Oban Holding AS
- Otc Invest AS
- Oda Tonstad Productions
- Osteopat Helene Andersen
- Onenomads Laska Marosi
- Ola Ingebrikt Dønnem
- Oslo Malerservice Oleinik
- Oslo Kommune Utdanningsetaten
- Oslo gate 39 AS
- Ole C. Loftesnes
- Oda Loui Østbakk
- Ordholderiet Yngvild Sørbye
- Oslo Soul Children
- Oslo Nøytrale Byråvakt
- Oh So Oslo AS
- Once In Oslo AS
- Ole Brumm Familiebarnehage
- Oslojolle Klubben Bundus
- Offshore Media Group AS
- Olav Kyrre Eiendom AS
- O Sole Solutions
- Oslo Assembly Production AS
- Oslo og Omegn Sjakkrets
- Optimal Kompetanse og Karriere
- Overå Fysioterapi, Manuellterapi, Akupunktur
- Olav Ramstad Birkevold Thelle
- Oberst Rodesvei 82b-E
- Ocht Kim André Hagen
- Oslo Irish Set Dancers
- Oberst Rodesvei 82b-E
- Oda Neoma Granath-Magelssen
- Orød Rådgivning Tor Øvrebø AS
- Oslo Bygg og Eiendom AS
- Oppsal Senter Boliggruppe D3 SA
- Orientalsk Visdom Av Sjasmin Butt
- On the Fritz IT Consulting AS
- Ole Moes vei 5 Sameie
- Ole Moes vei 5 Sameie
- Operasjonssykepleier Ida Ygemar Jæger-Eriksen
- Omni Posst Cato Jan Knem
- Oslo Bygg og Eiendom, Eiendom AS
- Oberst Rodes vei 60 A-D
- Oberst Rodes vei 60 A-D