| Lærkdesign AS | Real estate | 2025 |
| Løken Bygg AS | Construction | 1998 |
| Lønaas Kattepensjonat AS | Other services | 2025 |
| Løvlia Markastue AS | Professional & scientific | 2015 |
| M7 Performance AS | Professional & scientific | 2014 |
| Magmar Invest AS | | 2024 |
| Magnus Invest AS | Financial services | 2005 |
| Mailbroking AS | Professional & scientific | 2012 |
| Majaca Eiendom AS | Real estate | 2022 |
| Majaca Invest AS | Real estate | 2022 |
| Maki Holding AS | | 2025 |
| Malou AS | Wholesale & retail | 2025 |
| Manara AS | | 2007 |
| Mangt Slag AS | | 2026 |
| Marcel Holding AS | Financial services | 2017 |
| Marinbuddy AS | Professional & scientific | 2023 |
| Marine Brokers AS | Transport & logistics | 1961 |
| Marmaclub AS | Professional & scientific | 2020 |
| Marol Innovation AS | Professional & scientific | 1998 |
| Marwell-Hauge Consulting AS | Professional & scientific | 1990 |
| Marwell-Hauge Holding AS | | 1977 |
| Mathel AS | Financial services | 2009 |
| Matron AS | Professional & scientific | 1988 |
| Mazurek Invest AS | Financial services | 2016 |
| MB Boligservice AS | Construction | 2013 |
| Megahartz AS | | 2019 |
| Meiscron AS | | 2022 |
| Memko AS | Professional & scientific | 2009 |
| Methier Eiendom AS | Real estate | 2024 |
| Methier Holding AS | Real estate | 2024 |
| Mexa Invest AS | Financial services | 2015 |
| Midtveis Holding AS | Professional & scientific | 2015 |
| Milliways Invest AS | Real estate | 2014 |
| Minds AS | Professional & scientific | 1994 |
| Ministry of Stæsj AS | | 2023 |
| Mipmip AS | Real estate | 2025 |
| Miti Invest AS | Financial services | 2014 |
| MLG AS | Financial services | 2005 |
| Mmxxv AS | | 2025 |
| MNM Invest AS | Real estate | 2014 |
| Mogstad AS | Information & communication | 2000 |
| Morellino AS | Real estate | 2004 |
| Morten Jørgensen Holding AS | | 2022 |
| Mouton AS | Financial services | 2018 |
| Movu Mobility AS | Information & communication | 2017 |
| MP Entreprenør AS | Construction | 2024 |
| MP Renovering Holding AS | | 2025 |
| Multikam Sport & Kapital AS | | 2021 |
| MW Studio AS | Wholesale & retail | 2021 |
| Myra Center for Athlete Development AS | Education | 2024 |
| Med In AS | Wholesale & retail | 1988 |
| Nameabrand AS | Professional & scientific | 2014 |
| Neolithix AS | | 2025 |
| Nevrokiro Holding AS | Health & social care | 2015 |
| New Home Bygg AS | Construction | 2025 |
| Nextgoalagency AS | Administrative & support | 2026 |
| Nextor AS | Professional & scientific | 2006 |
| Nils Foldal AS | Real estate | 1956 |
| Ninna AS | Information & communication | 2016 |
| Noativ AS | Professional & scientific | 2015 |
| Nomatoc Consulting AS | Professional & scientific | 2022 |
| Noonskar Invest AS | | 2018 |
| Nor Kjeveortopedi AS | Health & social care | 2024 |
| Norbergh Forsikring AS | Financial services | 1997 |
| Nord Capital AS | | 2026 |
| Norelteam Holding AS | | 2019 |
| Norhagen Mur AS | Construction | 2014 |
| Normu AS | | 2026 |
| Norsk Kompetansesenter AS | Real estate | 2004 |
| Norsk Prospekteringselskap AS | Professional & scientific | 2007 |
| Norske Hager AS | Administrative & support | 2009 |
| Nortrans Holding AS | Professional & scientific | 1978 |
| Norvest Capital AS | Financial services | 2010 |
| Nouveaux Invest AS | Real estate | 2015 |
| Npcc AS | Information & communication | 2022 |
| Nye Eiksmarka Butikksenter AS | Real estate | 2025 |
| Oeconomica Da | Professional & scientific | 1998 |
| Oev Consulting AS | Professional & scientific | 2021 |
| Okeanos AS | Information & communication | 2023 |
| Omni Retail Holding AS | Professional & scientific | 2014 |
| Omniretail Consulting AS | Professional & scientific | 2026 |
| Opaker Butikkeiendom AS | | 2026 |
| Ophelia Invest AS | Financial services | 2007 |
| Opnii AS | Professional & scientific | 2012 |
| Organized Creative Business Ltd Nuf | Administrative & support | 2011 |
| Orkan Holding AS | Financial services | 2005 |
| Oslo Lyskilder AS | Wholesale & retail | 2017 |
| Osm Fredenlund AS | Information & communication | 2005 |
| Osm Fredenlund Invest AS | | 2025 |
| Otluma Holding AS | | 2026 |
| Overskudd AS | Information & communication | 2016 |
| Overskudd Opplæring AS | Education | 2004 |
| Overskuddklinikken AS | Health & social care | 2014 |
| Paal Myhrvang Ltd Nuf | Financial services | 2005 |
| Parking Morgans AS | Real estate | 1972 |
| Partnerkontoret AS | Arts & recreation | 2018 |
| Passiv Invest AS | Health & social care | 2016 |
| Pdo AS | Information & communication | 2016 |
| Pha Invest AS | | 2024 |
| Phemni AS | | 2022 |