Bedrift O - Stavern
- Ottem AS
- Orlogsbriggen Fredriksværn
- Ohlselia Panorama
- Oljeberget Invest AS
- Ohlselia Panorama
- Orlogsbriggen Fredriksværn
- Oksana Radulevych
- Outdoor Creative DA
- Oxholm Holding AS
- Oko Invest AS
- Olga Foldvik
- Odd Nerdrum
- Odd Sverre Kolstad
- Odd Wallebek Bedriftsrådgivning
- Orlogsbriggen Fredriksværns Venner
- Olaf Richard Klunderud
- Olsen 3D Printing
- Ole Andreas Foldvik
- Olsen-Nalum Geir
- Olav Kristian Oppedal
- Ole Leonard Haugene
- O & G Eiendom AS
- Olavs Firma Olav Rønneberg
- Odd Aksel Eide-Fredriksen
- Oda Kristine Instanes Design
- Ortopediteknikk Avd. Stavern - Ortopedisk Verksted
- Owal Kristin Elise Aall Dons-Wallebek