| Multisør AS | Administrative & support | 2025 |
| Muncor AS | Real estate | 2020 |
| Mur I Sør AS | Construction | 2004 |
| Mur I Sør Eiendom AS | Real estate | 2008 |
| Mur I Sør Forvaltning AS | Real estate | 2010 |
| Mur I Sør Utvikling AS | Real estate | 2007 |
| Murbygg Søgne AS | Construction | 1995 |
| Murer Bringedal AS | Construction | 2021 |
| Murerfirma Jan Øystein H. Nilsen AS | Construction | 2016 |
| Murerfirma Magne Lia AS | Construction | 2010 |
| Murerfirma Sven G Gangså AS | Construction | 2021 |
| Murmester Bjunes AS | Construction | 1999 |
| MVV 162 AS | Real estate | 2013 |
| MXT Holding AS | Information & communication | 2018 |
| MXT Services AS | Information & communication | 2024 |
| Mydlands Elektriske AS | Construction | 1998 |
| Møbel Holding AS | | 2026 |
| Møbel Invest Kristiansand AS | Wholesale & retail | 2026 |
| Møbelsnekker Professional AS | Construction | 2013 |
| N-Orcon AS | Professional & scientific | 2010 |
| N247 Media AS | Professional & scientific | 2024 |
| Naabel Management AS | Professional & scientific | 2013 |
| Neodesign AS | Construction | 2016 |
| Nesco AS | Professional & scientific | 1986 |
| Nettis AS | | 2024 |
| Netts AS | Wholesale & retail | 2022 |
| Nettstart Da | Information & communication | 2000 |
| New Hong Kong Ans | Hospitality | 1989 |
| Newtech AS | Professional & scientific | 2018 |
| Nicolaysen Betong AS | Construction | 2024 |
| Nicos Holding AS | Real estate | 2014 |
| Nikita Consulting AS | Wholesale & retail | 2024 |
| Nilsen IT. AS | Other services | 2015 |
| NLH Holding AS | | 2021 |
| Nodeland AS | Real estate | 2018 |
| Nodeland Eiendom AS | Real estate | 2006 |
| Nodenes Invest AS | Real estate | 2003 |
| Nordic Edge AI AS | Information & communication | 2025 |
| Norinspect AS | Real estate | 2015 |
| Norsk Dekor Og Fasadestein Ans | Manufacturing | 1999 |
| Norsk Stål AS | Manufacturing | 1990 |
| Norvix AS | Information & communication | 2026 |
| Norwegian Brands AS | Wholesale & retail | 2026 |
| Nubica AS | Real estate | 2016 |
| Ny-Hellesund Avløp SA | Water & waste | 2017 |
| Ny-Hellesund Utleie AS | Real estate | 2011 |
| Ny-Hellesund Vannverk SA | Water & waste | 1987 |
| Nye Heftenesvegen Veglag SA | Real estate | 2015 |
| Nyeskilt.No Nuf | Professional & scientific | 2007 |
| Nylund Kapital AS | | 2021 |
| Nymo Auto AS | Other services | 2012 |
| O. M. Pedersen Revisjon AS | Professional & scientific | 2009 |
| Oasen Eiendom G15 AS | Education | 2010 |
| Oasen Eiendom Søgne AS | Real estate | 2017 |
| Oasen Eiendom Vågsbygd AS | Real estate | 2024 |
| Oasen Holding Søgne AS | Education | 2014 |
| Oasen Kulturscene AS | Arts & recreation | 2017 |
| Oasen Skole Drammen AS | Education | 2018 |
| Oasen Skole Holding AS | Education | 2015 |
| Oddvin Invest AS | Agriculture & fishing | 2022 |
| Odel Consult AS | Real estate | 2001 |
| Odhin AS | | 2021 |
| Odison Invest AS | | 2021 |
| Oftenes Ved AS | Agriculture & fishing | 2023 |
| Oia AS | Wholesale & retail | 1996 |
| Ok I AS | | 2024 |
| Ok-E Eiendom AS | Real estate | 2023 |
| Ok-Helsehus AS | Health & social care | 2024 |
| Ole Johan Bueklev AS | Professional & scientific | 2022 |
| Olivian Holding AS | | 2020 |
| Olsen Og Stoveland AS | Administrative & support | 2024 |
| Omdal Anlegg AS | Construction | 2020 |
| Ommundsen Drift AS | | 2024 |
| Ommundsen Invest AS | Real estate | 2021 |
| Omni Invest AS | | 2005 |
| Omsorgskollektivet AS | Health & social care | 2020 |
| Omsorgskollektivet Holding AS | | 2024 |
| One Ocean Norway AS | Wholesale & retail | 2026 |
| Onkartgromt AS | Manufacturing | 2015 |
| Opp Kraftledningstjenester AS | Construction | 2003 |
| Ortisi Eiendom AS | Real estate | 2008 |
| Otry Invest AS | | 2024 |
| Ottar Jenssen AS | Professional & scientific | 2020 |
| Ovatronic AS | Manufacturing | 2020 |
| P&H Invest Da | Professional & scientific | 2007 |
| P. Try AS | Construction | 2005 |
| Parfymeriet Søgne AS | Wholesale & retail | 2024 |
| Pas Holding AS | Financial services | 2010 |
| Per Klungland Eiendom AS | Real estate | 2007 |
| Per Try AS | Construction | 2000 |
| Per Try Eiendom AS | Real estate | 2018 |
| Per Try Vann Og Avløp AS | Water & waste | 2021 |
| Per's Hage AS | Administrative & support | 2019 |
| Pettersen Ove Ans | Agriculture & fishing | 1991 |
| Pgas Holding AS | Professional & scientific | 2023 |
| Pgas Medinvest AS | | 2026 |
| Pharma Collections AS | Wholesale & retail | 2022 |
| Phronesis AS | | 2025 |
| Pictureit.No AS | Professional & scientific | 2015 |
| PJV Bygg AS | Real estate | 2026 |