| Mp.Invest AS | | 2024 |
| Mpbuh Apo AS | Wholesale & retail | 2025 |
| MR Eiendom & Utvikling AS | Real estate | 2025 |
| MR Håndverk AS | Construction | 2018 |
| MR Pizza AS | Hospitality | 1991 |
| Mrexx Eiendom AS | Real estate | 2020 |
| Mrexx Motor AS | Wholesale & retail | 2020 |
| MS Takst AS | Professional & scientific | 2025 |
| Msbr Invest AS | | 2021 |
| MSL Holdingselskap AS | Information & communication | 2019 |
| Mslt AS | | 2024 |
| Msnm Holding AS | | 2026 |
| Msoft AS | Professional & scientific | 1997 |
| MSW Holding AS | Professional & scientific | 2020 |
| MTG Invest Da | Wholesale & retail | 2024 |
| MTH Service Partner AS | Administrative & support | 2013 |
| Muida Tech AS | Information & communication | 2021 |
| Muji Sushi AS | Hospitality | 2023 |
| Multi Invest AS | Real estate | 1991 |
| Multi Systems AS | Professional & scientific | 1991 |
| Multifix Media & Consulting AS | Professional & scientific | 2013 |
| Multiforum Da | Wholesale & retail | 1996 |
| Mumm Holding AS | Construction | 2022 |
| Munk Holding AS | | 2024 |
| Munk Norway AS | Wholesale & retail | 2025 |
| MUNK1 AS | Manufacturing | 2012 |
| Mur Og Flis Oslo AS | Construction | 2019 |
| Murer Eriksen AS | Construction | 2015 |
| Murercompaniet AS | Construction | 2013 |
| Murlong Cres AS | Professional & scientific | 2023 |
| Murmester Skauge AS | Real estate | 2018 |
| Murmester Winnes Håndverk AS | Construction | 2012 |
| Mussomeli AS | Other services | 2017 |
| Musøya AS | Real estate | 2008 |
| Muurman AS | | 2023 |
| Muusøya 25 AS | Real estate | 2021 |
| Muusøya Holding AS | | 2022 |
| MWM AS | Information & communication | 2025 |
| Myfiber AS | Information & communication | 2025 |
| Myklestul Invest AS | Financial services | 2005 |
| Myntgata 12 AS | Real estate | 2014 |
| Myraveien AS | Real estate | 2015 |
| Myrøl Holding AS | Real estate | 2021 |
| Motorships A.S | Transport & logistics | 1963 |
| Målsponsor AS | Information & communication | 2026 |
| Mårbu Turisthytte AS | Hospitality | 2026 |
| Måto AS | | 2020 |
| Møbel Meglerne AS | Wholesale & retail | 2001 |
| Møbelonline AS | Wholesale & retail | 2015 |
| Møbelringen Drammen AS | Wholesale & retail | 2008 |
| Møllegaten 9 AS | Real estate | 2007 |
| Møller & Auster AS | Real estate | 2005 |
| Møller Graphics AS | Professional & scientific | 2005 |
| Møller Invest AS | Wholesale & retail | 2005 |
| Møllergården AS | Real estate | 2017 |
| Mørch-Hassel Consulting AS | Professional & scientific | 2026 |
| Mørch-Hassel Holding AS | | 2025 |
| Mørkåsen Eiendom Ans | Real estate | 1989 |
| Møteplasser AS | Hospitality | 2004 |
| N Invest AS | Financial services | 2009 |
| Nacos Valmarine AS | Information & communication | 1996 |
| Nagibi AS | Transport & logistics | 2011 |
| Naglestad Consulting AS | Information & communication | 2025 |
| Nagrand Invest AS | | 2019 |
| Nahim Jan Auto Expres Taxi Næring Da | Transport & logistics | 2009 |
| Nandine AS | Real estate | 2025 |
| Nanomed AI AS | Professional & scientific | 2017 |
| Nara Invest AS | Professional & scientific | 2021 |
| Nara Studio AS | Professional & scientific | 2021 |
| Nareveien SA | Real estate | 1973 |
| Nastro-Bygg AS | Construction | 2005 |
| Natale AS | Professional & scientific | 2024 |
| Natural Group AS | Wholesale & retail | 2021 |
| Naturlig Utvikling AS | Wholesale & retail | 2018 |
| Naust Wear AS | Wholesale & retail | 2021 |
| Navip AS | Professional & scientific | 2019 |
| Nbbo Byggservice AS | Administrative & support | 2002 |
| Nbbo Byggtek AS | Professional & scientific | 1996 |
| Nbbo Eiendomsmegling AS | Real estate | 1994 |
| Nbbo Utbygging AS | Real estate | 2004 |
| ND Transport AS | Transport & logistics | 2023 |
| Ndi Språkskole AS | Education | 2015 |
| NE 37 39 Holding AS | Real estate | 2020 |
| NE Arctos AS | Real estate | 2011 |
| NE Entreprenør AS | Construction | 2022 |
| NE Favusgården II AS | Real estate | 2016 |
| NE Havnegaten 1 AS | Real estate | 2011 |
| NE Havnegaten 2 AS | Real estate | 2011 |
| NE Havnegaten 4 AS | Real estate | 2011 |
| NE Lier AS | Real estate | 2011 |
| NE Mølnholtet 8 AS | Real estate | 2011 |
| NE Sørumsand Utvikling II AS | Real estate | 2017 |
| NE55 Drammen AS | Real estate | 2025 |
| Neash Solutions AS | Information & communication | 2015 |
| Nedberg Consult AS | Professional & scientific | 1999 |
| Nedre Eikervei 10 AS | Real estate | 2006 |
| Nedre Eikervei 14 AS | Real estate | 2006 |
| Nedre Eikervei 26 AS | Real estate | 1998 |
| Nedre Eikervei 65 AS | Real estate | 2018 |
| Nedre Eikervei AS | Real estate | 1910 |