| Mesterblikk Eiendom AS | Real estate | 2009 |
| Mesterblikk Invest AS | Construction | 2003 |
| Mestergruppen Arkitekter AS | Professional & scientific | 1991 |
| Mestergruppen Entreprenør AS | Construction | 2004 |
| Mesterlandskap AS | Administrative & support | 2023 |
| Mesterteam AS | Construction | 2024 |
| Mestertømrerbygg AS | Construction | 2020 |
| Meta Holding AS | Hospitality | 2016 |
| Metagen AS | Information & communication | 2020 |
| Metari Invest AS | Professional & scientific | 2005 |
| Mete AS | Information & communication | 2014 |
| Meteora AS | Information & communication | 2019 |
| Metertech AS | Professional & scientific | 2014 |
| Metinor AS | Information & communication | 2023 |
| Metiq AS | Professional & scientific | 2022 |
| Metko AS | Real estate | 1996 |
| Metro 2 AS | Hospitality | 2022 |
| Metron AS | Arts & recreation | 2016 |
| Mett Og Mektig AS | Hospitality | 2026 |
| Mevemi Impact AS | | 2025 |
| Mex-Co Holding AS | | 2021 |
| MFL Invest AS | | 2022 |
| Mfoss Holding AS | | 2023 |
| MG Salg Og Utleie AS | Wholesale & retail | 2008 |
| MGH Holding AS | Financial services | 2007 |
| MGM Eiendom AS | Real estate | 2015 |
| MHB AS | Real estate | 2020 |
| MHM Holding AS | Real estate | 2017 |
| MHN AS | | 2024 |
| Mho Invest AS | | 2020 |
| MHT Invest AS | | 2025 |
| Mi Invest AS | Real estate | 2019 |
| Mia AS | Wholesale & retail | 2014 |
| Mia Health AS | Information & communication | 2016 |
| Micaelsen Eiendom AS | Real estate | 2000 |
| Micaelsen Eiendom Holding AS | Real estate | 2023 |
| Michaelsen Holding AS | Real estate | 2005 |
| Microchip Technology Norway AS | Professional & scientific | 2002 |
| Microingress Nuf | Financial services | 2007 |
| Micronax AS | Professional & scientific | 2008 |
| Mictlan AS | Real estate | 2015 |
| Midcom Trondheim A/S | Manufacturing | 1987 |
| Middelhavets Marked AS | Wholesale & retail | 2012 |
| Midelfart Invest AS | | 2026 |
| Midfur Holding AS | | 2022 |
| Midfur Invest AS | | 2022 |
| Midgard Vind AS | Energy | 2018 |
| Midgard Vind Holding AS | Energy | 2018 |
| Midt Consulting AS | | 2020 |
| Midt Inneklima AS | Construction | 2025 |
| Midt Multiservice AS | Administrative & support | 2023 |
| Midt Norge Rådhus AS | | 1989 |
| Midt-Bygg AS | Construction | 2015 |
| Midt-Nordisk Gjenvinning Ans | Wholesale & retail | 2000 |
| Midt-Norge Eiendomsforvaltning AS | Real estate | 2016 |
| Midt-Norge Eiendomsutvikling AS | Real estate | 2010 |
| Midt-Norge Takst AS | Professional & scientific | 2005 |
| Midt-Norsk Salgssenter AS | Administrative & support | 2026 |
| Midt-Norsk Sikkerhetsopplæring AS | Education | 1999 |
| Midtbyen Bil Mc-Skole Ans | Education | 1989 |
| Midtbyen Eiendomsmegling AS | Real estate | 2024 |
| Midtbyen Legesenter AS | Health & social care | 2013 |
| Midtbyen Logopedi AS | Health & social care | 2023 |
| Midtbyen Regnskap AS | Professional & scientific | 1987 |
| Midtbyen Sykkel AS | Wholesale & retail | 2021 |
| Midtbyen Øyeklinikk AS | Health & social care | 2012 |
| Midtlyng Og Mørreaunet AS | Hospitality | 2024 |
| Midtnorsk Filmsenter AS | Information & communication | 2005 |
| Midtnorsk Glass Service AS | Construction | 2026 |
| Midtnorsk Renhold & Transport AS | Administrative & support | 2021 |
| Midtsand Eiendom AS | Real estate | 2022 |
| Midtsand Invest AS | | 2021 |
| Midtsandveien 12 AS | Real estate | 2018 |
| Mifi AS | | 2006 |
| Migo Eiendom AS | Real estate | 1995 |
| Migosenteret AS | Real estate | 2006 |
| Migris AS | Information & communication | 2005 |
| Mijos AS | Real estate | 2016 |
| Mika Enterprise AS | Construction | 2022 |
| Mika-Invest AS | | 2023 |
| Mikalsen Bakeri & Konditori AS | Manufacturing | 2002 |
| Mikalsen Bakeri Produksjon AS | Manufacturing | 2010 |
| Milano Nardo AS | Hospitality | 2010 |
| Miles Ahead AS | Professional & scientific | 2021 |
| Mili Økonomi AS | Professional & scientific | 2013 |
| Millenium Servicesenter AS | Administrative & support | 2025 |
| Millenium Transport AS | Transport & logistics | 2025 |
| Millennium Holding 1 AS | Transport & logistics | 2023 |
| Milok Invest AS | | 2020 |
| Min Kollasj AS | | 2025 |
| Mind AS | Education | 2010 |
| Mindfit AS | Information & communication | 2014 |
| Mindgrit AS | Education | 2019 |
| Mindo Trondheim AS | Real estate | 2019 |
| Mindpoint AS | Professional & scientific | 2012 |
| Mindsight AS | Professional & scientific | 2025 |
| Minervini AS | | 2024 |
| Mini AS | Administrative & support | 1997 |
| Minillhaugen AS | | 2021 |
| Minit North AS | Other services | 2024 |