| Mikroprosjekt AS | Information & communication | 2025 |
| Mila Capital AS | | 2025 |
| Miljøretur AS | Information & communication | 2025 |
| Min Byggpartner AS | Construction | 2025 |
| Minus Solutions AS | Professional & scientific | 2018 |
| MKS Bergen Eiendom Og Teknisk AS | Construction | 2015 |
| MNS Eiendom AS | Real estate | 2015 |
| Moberg Invest AS | Real estate | 2005 |
| Moberg Legesenter AS | Health & social care | 2024 |
| Mobergs Fysikalske AS | Health & social care | 2002 |
| Mobra Kapital AS | Administrative & support | 2019 |
| Moderne Eiendom AS | Real estate | 2011 |
| Moldegaard AS | Real estate | 1982 |
| Moldestad Fjellsprengning AS | Construction | 2014 |
| Moly AS | Real estate | 1990 |
| Moral Holding AS | Professional & scientific | 2015 |
| Morten Halhjem Bygg AS | Construction | 2016 |
| Motorfest AS | Administrative & support | 2021 |
| Multi Entreprenør AS | Construction | 2017 |
| Multiax AS | Manufacturing | 2021 |
| Mvaccounting AS | Professional & scientific | 2019 |
| Møbelsenteret Eiendom Drotningsvik AS | Real estate | 2021 |
| Møbelsenteret Eiendom Os AS | Real estate | 2021 |
| Møbelsenteret Eiendom Stord AS | Real estate | 2021 |
| Møbelsenteret Lagerlokale Os AS | Real estate | 2021 |
| Møbelsenteret På Nordås Eiendom AS | Real estate | 1947 |
| Møbelsenteret På Nordås Eiendom Holding AS | Wholesale & retail | 2021 |
| Møsnuken Holding AS | | 2024 |
| Nabai AS | Construction | 2023 |
| Namastey Os AS | Hospitality | 2025 |
| Naturkost Os AS | Wholesale & retail | 2018 |
| Naturlige Kjøkken AS | Hospitality | 2021 |
| Nautilus Feed AS | Professional & scientific | 2020 |
| Navis Group AS | Professional & scientific | 2026 |
| Nestcare AS | | 2026 |
| Nestwork Group AS | Administrative & support | 2025 |
| Nexor AS | Real estate | 2023 |
| Niclas Hjelle Holding AS | | 2024 |
| Nilsen Transporttjeneste AS | Transport & logistics | 2017 |
| Nimaco AS | Real estate | 2002 |
| Ninnistrikk AS | Wholesale & retail | 2024 |
| Njøsen Hilding AS | Financial services | 2018 |
| Nord Trail AS | Transport & logistics | 2023 |
| Nord Trail Da | Transport & logistics | 2012 |
| Norden Maritim AS | Manufacturing | 2017 |
| Nordic Beauty AS | Wholesale & retail | 2019 |
| Nordic Eco-Tech AS | | 2020 |
| Nordic-Eco AS | Wholesale & retail | 2021 |
| Nordmarka Os AS | Real estate | 2018 |
| Nordre Drotningsvik 12 AS | Real estate | 2022 |
| Nordre Lyseparken AS | Real estate | 2026 |
| Nordtrading Butikk AS | Wholesale & retail | 2006 |
| Normo Automasjon AS | Wholesale & retail | 1996 |
| Norør AS | Construction | 1985 |
| Norør Butikken AS | Wholesale & retail | 2006 |
| Norør Holding AS | Construction | 2005 |
| Nova Food Da | Wholesale & retail | 2000 |
| Nuvolari AS | Professional & scientific | 2020 |
| Nygårdsvegen 12 AS | Real estate | 2022 |
| Nyta Maten AS | Wholesale & retail | 2023 |
| Næringshus Os AS | Real estate | 2025 |
| Nøkkelen Hårstudio AS | Other services | 2012 |
| Oasen Leiligheter AS | | 2025 |
| Obb AS | Construction | 2018 |
| Ocean for the Ladies | Education | 2008 |
| Octaos AS | Information & communication | 2011 |
| Odd Tøsdal AS | Real estate | 1968 |
| Of Eiendom AS | Real estate | 1952 |
| Ofl AS | Professional & scientific | 2024 |
| Ojx AS | | 2024 |
| Ome Finans AS | Real estate | 1990 |
| Omsorgspartner Vekst AS | Health & social care | 2025 |
| Omsorgspartner Vestland AS | Health & social care | 2011 |
| ONE4SAFETY AS | Information & communication | 2022 |
| Opataris AS | Information & communication | 2018 |
| Optiinvest AS | Real estate | 2007 |
| Optiker Bakketeig Os AS | Wholesale & retail | 2013 |
| Orku Da | Manufacturing | 2021 |
| Os / Byens Trafikkskole AS | Education | 1994 |
| Os Allmennpraksis Da | Health & social care | 2001 |
| Os Anlegg AS | Construction | 2015 |
| Os Auto AS | Other services | 2005 |
| Os Autosalg AS | Wholesale & retail | 2026 |
| Os Bil AS | Professional & scientific | 2021 |
| Os Biljard & Sportsbar AS | Arts & recreation | 2002 |
| Os Bilsenter AS | Wholesale & retail | 2017 |
| Os Bilsenter Service AS | Other services | 2020 |
| Os Bilutleie AS | Administrative & support | 2020 |
| Os Blikk & Fasade AS | Construction | 2007 |
| Os Blikk Og Fasade AS | Manufacturing | 2021 |
| Os Blomsterdesign AS | Wholesale & retail | 2023 |
| Os Blomsterservice AS | Wholesale & retail | 2021 |
| Os Brygge AS | Real estate | 2019 |
| Os Båthotell Ans | Agriculture & fishing | 1991 |
| Os Caravan & Fritid AS | Wholesale & retail | 2018 |
| Os Caravanservice AS | Other services | 2024 |
| Os Data AS | Information & communication | 2024 |
| Os Dekk Og Servicesenter AS | Other services | 1991 |
| Os Dyreklinikk AS | Professional & scientific | 2004 |
| Os Elektro AS | Construction | 2022 |