| Me-Coaching AS | Education | 2025 |
| Media 3 Rana AS | Information & communication | 2000 |
| Mehan Holding AS | | 2021 |
| Mekanikeren AS | Other services | 1991 |
| Mellomvika 1 AS | Real estate | 2018 |
| Mellomvika 35 AS | Real estate | 2012 |
| Mellomvika 37 AS | Real estate | 2022 |
| Mellomvika 51 AS | Real estate | 2018 |
| Memmra Eiendom AS | Real estate | 2017 |
| Merkantil Consult AS | Professional & scientific | 2009 |
| Merkantil Holding AS | Real estate | 2009 |
| Merlin Kids Mo I Rana AS | Wholesale & retail | 1997 |
| Mester Holding AS | Real estate | 1995 |
| Meyer AS | Real estate | 2000 |
| Meyer Holding AS | Real estate | 2002 |
| Meyer Servering AS | Hospitality | 2002 |
| Meyergrunn AS | Real estate | 2019 |
| Meyergården AS | Hospitality | 1975 |
| Meyergården Eiendom AS | Hospitality | 2013 |
| Meyergården Turisthotell AS | Hospitality | 1999 |
| Meyers Gull Og Sølv AS | Wholesale & retail | 2000 |
| Meyership AS | Transport & logistics | 1987 |
| Meyership Eiendom AS | Real estate | 2006 |
| MHR Holding AS | Real estate | 2020 |
| Micma Interior Design AS | Wholesale & retail | 2012 |
| Mics AS | Construction | 2017 |
| Midgardsormen AS | Information & communication | 2015 |
| Midt-Norsk Eiendomsinvest AS | Real estate | 2017 |
| Midtbyen Eiendom AS | Real estate | 2008 |
| Midtre Gate 13 AS | Real estate | 2020 |
| Mik Marketing AS | Professional & scientific | 2018 |
| MIKO SENTER Ingebrigtsen/Kjenstad ANS | Information & communication | 1988 |
| Milano Mo I Rana AS | Hospitality | 2015 |
| Miljø Rent Nord AS | Administrative & support | 2012 |
| Miljømetall AS | Water & waste | 2023 |
| Miljøteknikk Terrateam AS | Water & waste | 1987 |
| Minerals Norway AS | Information & communication | 2011 |
| Mip Miljøkraft AS | Energy | 2017 |
| Mip RS AS | Real estate | 2006 |
| Miras Defence & Protection AS | | 2026 |
| Miras Elektro AS | Construction | 2017 |
| Miras Group AS | Manufacturing | 2012 |
| Miras Hydraulikk AS | Manufacturing | 2017 |
| Miras Solutions AS | Manufacturing | 1989 |
| Miras Velferd AS | Health & social care | 2024 |
| Mirror Inn AS | Real estate | 2022 |
| Mj-Holding AS | Financial services | 2019 |
| MJ. Holding AS | | 2026 |
| Mjellegården AS | Real estate | 2022 |
| Mjølner Entreprenør AS | Construction | 2023 |
| Mkdk Holding AS | Construction | 2024 |
| MKG Holding AS | | 2017 |
| MM Agenturer AS | Wholesale & retail | 2024 |
| MMS AS | Construction | 2026 |
| Mo Barbershop 1 AS | Other services | 2026 |
| Mo Bygg & Isolasjon Da | Construction | 1988 |
| Mo Dyreklinikk AS | Professional & scientific | 2004 |
| Mo Eiendomsselskap AS | Real estate | 2013 |
| Mo Eiendomsservice Da | Real estate | 2008 |
| Mo Fjernvarme AS | Energy | 1999 |
| Mo Gravferd AS | Other services | 2008 |
| Mo Handelspark AS | Real estate | 2007 |
| Mo I Rana Blomster AS | Wholesale & retail | 2013 |
| Mo I Rana Camping AS | Real estate | 2007 |
| Mo I Rana Dypvannskai AS | Real estate | 2023 |
| Mo I Rana Grill AS | Hospitality | 2020 |
| Mo I Rana Hotelldrift AS | Hospitality | 2024 |
| Mo I Rana Specsavers AS | Wholesale & retail | 2018 |
| Mo Industripark AS | Manufacturing | 1946 |
| Mo Industritransport AS | Transport & logistics | 1989 |
| Mo Multiservice AS | Administrative & support | 2025 |
| Mo NDT & Inspection AS | Professional & scientific | 2024 |
| Mo Rørservice AS | Construction | 2001 |
| Mo Shipping Agency AS | Transport & logistics | 1989 |
| Mo Taxisentral AS | Transport & logistics | 1996 |
| Mo Tekstil Ans | Wholesale & retail | 1995 |
| Mo Varme AS | Wholesale & retail | 2018 |
| Mo Veihjelp AS | Transport & logistics | 2023 |
| Mo Veiservice AS | Wholesale & retail | 1999 |
| Mo Vending AS | Wholesale & retail | 2024 |
| Moba Holding AS | | 2021 |
| Mobil AS | Other services | 2019 |
| Mofjellet Berghaller AS | Real estate | 1988 |
| Mohamad Saleh Dagligvarer AS | Wholesale & retail | 2024 |
| Moheia Eiendom AS | Real estate | 2005 |
| Moheia Fysikalske AS | Health & social care | 2000 |
| Moheia Kantine Ans | Hospitality | 1998 |
| Moholmen Holding AS | Wholesale & retail | 1975 |
| Moholmen Tre Og Flis AS | Construction | 2026 |
| Molvik Holding AS | | 2022 |
| Momal AS | Construction | 2024 |
| Momek Civil AS | Construction | 2007 |
| Momek Group AS | Manufacturing | 2012 |
| Momek Invest AS | Real estate | 2020 |
| Momek Løvold AS | Professional & scientific | 2021 |
| Momek PT Modular AS | Wholesale & retail | 2014 |
| Momek Robotics AS | Professional & scientific | 2021 |
| Momek Services AS | Manufacturing | 2008 |
| Momek Tappingmate AS | Professional & scientific | 2021 |
| Moment Rana AS | Real estate | 1960 |