| Memm Drift AS | Construction | 2022 |
| Memm Eiendom AS | Real estate | 2022 |
| Memm Holding AS | Construction | 2022 |
| Memoriacraft AS | Wholesale & retail | 2018 |
| Mentor Kapital AS | Professional & scientific | 2004 |
| Mer Film AS | Information & communication | 2011 |
| Mer Film Invest AS | Information & communication | 2021 |
| Merlo | Administrative & support | 2008 |
| Mesterteam Tromsø AS | Construction | 2006 |
| Metablock AS | Professional & scientific | 2022 |
| Methanxtra AS | Professional & scientific | 2025 |
| Metis Invest AS | Professional & scientific | 2005 |
| Meyer Ventures AS | | 2024 |
| MGS Capital AS | | 2023 |
| Mi Capital AS | | 2026 |
| Midgard AS | Hospitality | 2015 |
| Midgard Holding AS | Hospitality | 2021 |
| Midnight Munchies AS | Hospitality | 2026 |
| Miehlos AS | Information & communication | 2014 |
| Mikalsen Revisjon AS | Professional & scientific | 2025 |
| Mikkelsen Eiendom AS | Real estate | 2021 |
| Mikko AS | Wholesale & retail | 1971 |
| Mikse AS | Information & communication | 2013 |
| Milad Shakir Holding AS | Arts & recreation | 2024 |
| Milano Holding AS | | 2025 |
| Milano Pizzeria Tromsø AS | Hospitality | 2025 |
| Miljø Forbrenning AS | Wholesale & retail | 2011 |
| Miljøpartiet De Grønne Troms Og Finnmark | Other services | 2013 |
| Millifoke AS | | 2020 |
| Mindgest AI AS | Information & communication | 2025 |
| Mineplaystudios AS | Information & communication | 2026 |
| Mineralutvikling Ans | | 1988 |
| Minerva Medica AS | Health & social care | 2021 |
| Minken Næringspark 4 AS | Real estate | 2009 |
| Minken Næringspark 6 AS | Real estate | 2011 |
| Minsin Invest AS | | 2022 |
| Mirai Holding AS | | 2020 |
| Miss Sofi AS | Other services | 2016 |
| MJ Invest AS | | 2019 |
| MJM Finans AS | Administrative & support | 2024 |
| Mjph Invest AS | | 2026 |
| MK Invest- Og Kapitalutvikling AS | Real estate | 2025 |
| MK Investering & Eiendomsutvikling AS | Real estate | 2026 |
| Mkantonsen AS | | 2023 |
| Mkrshift AS | Professional & scientific | 2025 |
| MKS Nord AS | | 2021 |
| Mo Kompetanse AS | Construction | 2024 |
| Mobildialog AS | Wholesale & retail | 2006 |
| Mobula-Holding AS | | 2025 |
| Modus Vivendi Da | Professional & scientific | 2001 |
| Moegården AS | Real estate | 2022 |
| Moegården Holding AS | Real estate | 2022 |
| Moens Konsulentkontor AS | Professional & scientific | 1993 |
| Mofi Holding AS | Financial services | 2017 |
| Mohammad Frisør AS | Other services | 2024 |
| Moher AS | Transport & logistics | 2020 |
| Moinvest AS | | 2023 |
| Mok AS | Hospitality | 2015 |
| Moldalia Eiendomsforvaltning AS | Real estate | 2025 |
| Moldalia Invest AS | | 2025 |
| Moloen AS | Administrative & support | 2017 |
| Moloen Media AS | Information & communication | 2020 |
| Moloen People AS | Administrative & support | 2023 |
| Moloen Sustainability AS | Professional & scientific | 2022 |
| Moment Norway AS | Administrative & support | 2024 |
| Momentum Distribution AS | Wholesale & retail | 2025 |
| Mona Abelsen Store AS | Wholesale & retail | 2015 |
| Moneta AS | Real estate | 2005 |
| Moneykj/Em Invest AS | | 2024 |
| Monican AS | | 2026 |
| Monoidal AS | | 2025 |
| Montevideo Tromsø AS | Information & communication | 2020 |
| Montmartre AS | Professional & scientific | 2024 |
| Montørsentralen Ans | Construction | 1999 |
| Mor 24 AS | Real estate | 2019 |
| Morgen Studio AS | Information & communication | 2025 |
| Mormors Kræmmerhus Da | Manufacturing | 1996 |
| Mors Mat AS | Hospitality | 2024 |
| Mortensen Consult AS | Professional & scientific | 2019 |
| Motion Corporation AS | Information & communication | 2013 |
| Motus Læring AS | Education | 2019 |
| Moveuptjenester AS | Transport & logistics | 2025 |
| Movik AS | Real estate | 2005 |
| Mpower AS | Information & communication | 2002 |
| Mrj-Holding AS | Wholesale & retail | 2019 |
| Mrksoft AS | Information & communication | 2024 |
| MRP AS | Construction | 2015 |
| MS Eiendom AS | Real estate | 2014 |
| MSX Holding AS | | 2025 |
| MTF Trading Nuf | Real estate | 2005 |
| Mtkm Aktiv AS | | 2023 |
| Muli AS | Real estate | 2019 |
| Multi Eiendom AS | Real estate | 2000 |
| Multi Fritid AS | Arts & recreation | 2005 |
| Multi Montering AS | Construction | 2014 |
| Multi-Gh AS | | 2024 |
| Multiply Invest II AS | | 2016 |
| Multiservice Tromsø AS | Construction | 2025 |
| Munch Og Kufaas Invest AS | | 2021 |
| Munin Invest AS | Real estate | 2005 |