| MKF Shipping AS | Transport & logistics | 2018 |
| Mki Media AS | Information & communication | 2013 |
| Mlie Invest AS | | 2026 |
| MLP Holding AS | Real estate | 2018 |
| MLP Invest AS | | 2019 |
| MLT Invest AS | Real estate | 2013 |
| MM Sport Invest AS | | 2021 |
| MMJ Asset Management AS | Real estate | 2020 |
| MMJ Eiendom AS | Real estate | 2021 |
| MML Holding AS | | 2024 |
| MML Lomeland Mur AS | Construction | 2018 |
| Mmø Holding AS | | 2008 |
| MN Beauty AS | Wholesale & retail | 2023 |
| MN Invest AS | Real estate | 2020 |
| MN Solutions AS | Information & communication | 2025 |
| MND Holding AS | Construction | 2017 |
| MNK AS | Professional & scientific | 2024 |
| Moa AS | Real estate | 2020 |
| Mobildata Sørlandsparken AS | Information & communication | 2004 |
| Mobile Auto Sør AS | Wholesale & retail | 2020 |
| Mobile Sørlandsparken AS | Other services | 1987 |
| Mobilityone AS | Administrative & support | 2026 |
| Modell Møbler Holding AS | | 2014 |
| Modell Pels - Gustaf Hansson AS | Real estate | 1965 |
| Modern Qhse Consulting AS | Health & social care | 2023 |
| Modus Mur AS | Construction | 2017 |
| Moen Eckhoff Holding AS | Real estate | 2019 |
| Mofr Invest AS | | 2025 |
| Moheim Eiendom AS | Real estate | 2006 |
| Moi Rør AS | Construction | 1994 |
| Mois Thaimassasje AS | Other services | 2023 |
| Mokoba AS | Professional & scientific | 2021 |
| Molesto AS | Real estate | 2019 |
| Molivito AS | Real estate | 2005 |
| Mollandsveien Eiendom AS | | 2025 |
| Mome AS | Professional & scientific | 2013 |
| Mome Invest AS | Information & communication | 2019 |
| Moment Analyse AS | Professional & scientific | 2013 |
| Moment Digital AS | Professional & scientific | 2019 |
| Moment Holding AS | Real estate | 2016 |
| Moment Technology AS | Professional & scientific | 2021 |
| Moment Utvikling AS | Real estate | 2016 |
| Momentum Investments AS | | 2026 |
| Momentum Management AS | Professional & scientific | 2007 |
| Momentum Trade AS | Professional & scientific | 2026 |
| Mona Invest AS | Professional & scientific | 2023 |
| Mondent Living AS | Wholesale & retail | 2024 |
| Moneymaker Holding AS | Real estate | 2005 |
| Monica Nyhus AS | Professional & scientific | 2019 |
| Monica Nyhus Holding AS | Professional & scientific | 2021 |
| Monir Holding AS | Real estate | 2021 |
| Monir Stjerne AS | Real estate | 2021 |
| Monitra AS | Wholesale & retail | 2021 |
| Monkeys Holding AS | | 2017 |
| Monkeytours AS | Administrative & support | 2025 |
| Monopole Wines AS | Wholesale & retail | 2013 |
| Monro AS | | 2025 |
| Monsterfabrikken AS | Real estate | 2020 |
| Monstunet Holding AS | | 2024 |
| Monsun Frisør AS | Other services | 2007 |
| Monsør AS | Construction | 2024 |
| Montasje Og Varme AS | Construction | 2017 |
| Monte Christo Hills AS | Real estate | 2016 |
| Monty Holding AS | Manufacturing | 2016 |
| Montør I Sør AS | Construction | 2009 |
| Montøren AS | Construction | 2012 |
| Moodcat AS | Information & communication | 2020 |
| Moogdal AS | Other services | 2015 |
| Moore Advisors Sør AS | Professional & scientific | 1981 |
| Mop Holding AS | | 2023 |
| Mor Lamb Holding AS | | 2026 |
| Morah Holding AS | | 2026 |
| Mordor AS | Wholesale & retail | 2009 |
| Morency Consulting AS | Professional & scientific | 2026 |
| Morgengrysletta AS | Professional & scientific | 2019 |
| Morild Investment AS | | 2023 |
| Morild Norway AS | Wholesale & retail | 2021 |
| Morran Holding AS | | 2025 |
| Morse AS | Real estate | 2002 |
| Morsy Eiendom AS | Real estate | 2024 |
| Morten Berggren AS | Real estate | 2023 |
| Morten G.H AS | | 2025 |
| Morten Knutsen Holding AS | Financial services | 2016 |
| Morten Rønning Holding AS | Financial services | 2014 |
| Moru AS | Information & communication | 2021 |
| Mosby Bensin Eiendom AS | Real estate | 2005 |
| Mosby Utvikling AS | Real estate | 2016 |
| Mosdale Eiendom AS | Real estate | 2007 |
| Mose Studios AS | Information & communication | 2019 |
| Mosfjell AS | Real estate | 2004 |
| Mosiv Invest AS | | 2025 |
| Moslihn AS | Real estate | 1976 |
| Moso AS | Information & communication | 2016 |
| Mosprince AS | Real estate | 2001 |
| Mosring AS | Real estate | 2013 |
| Moss Logistikkbygg AS | Real estate | 2017 |
| Mossmann Holding AS | | 2023 |
| Mostrem AS | Administrative & support | 2023 |
| Mostrem Holding AS | Information & communication | 2023 |
| Mostun AS | | 2002 |