Bedrift O - Namsos
- Olaiosen AS
- Oppned AS
- Ouzo
- Ouzo
- Oleksii Kosiakov
- Oksana Shmulii
- Optimisten Dagsenter
- Olsen Vasketjenester
- Optiheat Energi AS
- Otterøy Sokn
- Oi Eiendom AS
- Opal Maritime AS
- Odin Eiendommer AS
- Odd Ingebrigtsen AS
- Osloveien 19 AS
- Ola-Kaviar AS
- Ori Holding AS
- Oi Holding AS
- Overhalla Mekaniske AS
- Optiker Ingebrigtsen
- Oleksandr Kazanskyi
- Oksana Shmulii
- Ole Leirvik
- Oplands Nødnettopplæring
- Oxijoa Renhold AS
- Oleksandr Sanduliarz
- Olena Andrieieve
- Oda Lundstadsveen
- Oleksandr Dekhnich
- Oleksandr Surych
- Olha Zapovitriana
- Olesia Kalynovska
- Oleksii Batsman
- Olha Sholak
- Olena Kosarieva
- Otterøyingen Vel
- Oleksii Suprunovych
- Ola Liljefjell
- Otterbekk Bil AS
- Olderstad Formidling AS
- Olderstad Holding AS
- Oddbjørn Aar
- Osman Monas Beauty
- Otto Moe Bilutleie AS
- Otto Moe Holding AS
- Opplysningen 1881 AS Avd. Namsos
- Otto Moe Eiendom AS
- Osloveien 17 Trondheim AS
- Ole Bruun Olsen AS
- Otto Moe avd. Namsos
- Odd Marius Skjelbred
- Ole Petter Dahl
- Ole Petter Dahl
- Olav Magne Vannebo
- Oddleiv Bernhard Havik
- Otto Moe Eiendom Grong AS
- Otto Moe Eiendom Rørvik AS
- Olav Duun videregående skole
- O. E. Ness Teknisk Konsulent
- Oriflame Namsos Hill K Fagernes
- Oasen Svømme og Miljøsenter Badeland
- Odden Båt- og Rorbuutleie, F.R.Pettersen