| Jamco AS | Professional & scientific | 2006 |
| Jan Bye AS | Wholesale & retail | 1988 |
| Janfo Invest AS | Professional & scientific | 2014 |
| Jazzcode AS | Arts & recreation | 2007 |
| Jeløy Va-Drift SA | Water & waste | 2016 |
| Jeløy Va-Utvikling SA | Professional & scientific | 2016 |
| Jga Invest AS | Financial services | 2012 |
| Ji Sport Norge Nuf | Wholesale & retail | 2005 |
| JK Invest Holding AS | Information & communication | 2021 |
| Jo Henrik Eiendom AS | Real estate | 2017 |
| Jo Henrik Invest AS | Real estate | 2006 |
| Jonas Strand Gravli AS | Arts & recreation | 2017 |
| Jonells Pizza Og Bar AS | Hospitality | 2025 |
| Jtj-Invest AS | Real estate | 2006 |
| Justai AS | Professional & scientific | 2025 |
| Jydsk Rørentreprise AS | Construction | 1998 |
| Jørgenrud Invest AS | | 2021 |
| K.A Holding AS | | 2022 |
| Kaag AS | | 2022 |
| Keystone AS | Real estate | 2004 |
| Kimusan Invest AS | | 2021 |
| King Equity AS | | 2026 |
| Kiosk & Spill AS | Wholesale & retail | 1997 |
| Kl/Cdk Norge | Professional & scientific | 2012 |
| Knut Thome Holding AS | Manufacturing | 2023 |
| Kolderup Invest AS | Real estate | 2005 |
| Kolseth Gruppen AS | Financial services | 2015 |
| Kolåstoppen Holding AS | | 2021 |
| Kom Forlag AS | Information & communication | 1990 |
| Kondishuset AS | Arts & recreation | 2014 |
| Kontoret I Son AS | Real estate | 2023 |
| KT11 Holding AS | | 2021 |
| Kulturtolk AS | Professional & scientific | 2023 |
| Kunstagent AS | Professional & scientific | 2025 |
| Kverneng AS | Real estate | 2020 |
| Kystlinjen Va SA | Water & waste | 2013 |
| La-Sa Marine Service AS | Manufacturing | 2000 |
| Laaby Holding AS | Real estate | 2020 |
| Landgraff Advisory AS | Professional & scientific | 2016 |
| Landgraff Invest AS | Professional & scientific | 2016 |
| Larsen Anleggsservice AS | Construction | 1992 |
| Larsen Gbe AS | Construction | 2002 |
| Larsen Utvikling AS | Construction | 2011 |
| Larsens Skovservice | Construction | 2001 |
| Lasse Steen Invest AS | Financial services | 2012 |
| Legal & Claims Solutions Holding AS | | 2025 |
| Lekang AS | Information & communication | 2010 |
| Leve & Blomstre AS | Education | 2021 |
| Lilleby Utvikling AS | Real estate | 2020 |
| Lillelørdag Holding AS | | 2026 |
| Linami Invest AS | | 2024 |
| Lippert AS | Professional & scientific | 2018 |
| Lisleby Rør Og Reparasjoner AS | Construction | 1993 |
| LK1 Holding AS | | 2026 |
| Ll-Consulting AS | Professional & scientific | 2022 |
| Lobbe Invest AS | | 2019 |
| Loci Wines AS | Wholesale & retail | 2021 |
| Lorentzen & Partners AS | Real estate | 2005 |
| Lue AS | Real estate | 2019 |
| Lundberg Holding AS | Professional & scientific | 2021 |
| Lyd & Lek AS | Wholesale & retail | 2012 |
| Lypark AS | Real estate | 2005 |
| Lær IT | Information & communication | 2014 |
| Lööv-Olsen Holding AS | | 2023 |
| Løsningsorientert Øivind Lunde AS | Other services | 2014 |
| Magida Holding AS | | 2017 |
| Magu Holding AS | | 2021 |
| Maritime Rescue Technologies AS | Professional & scientific | 2016 |
| Mart AS | Wholesale & retail | 2005 |
| Martech Consulting AS | Professional & scientific | 2019 |
| Martin Steen Invest AS | | 2012 |
| Marwol AS | | 2021 |
| Mats Gaupset Holding AS | | 2023 |
| Mauseth Holding AS | Information & communication | 2019 |
| Maximize Mgmt AS | Professional & scientific | 2024 |
| MBF Invest AS | | 2005 |
| MDH Bygg Aktiebolag Nuf | Construction | 2010 |
| Meadow AS | Professional & scientific | 2020 |
| Meak AS | Professional & scientific | 2026 |
| Media Technology Group AS | Wholesale & retail | 1996 |
| Mel Vestby 18 AS | Real estate | 2022 |
| Mel Vestby 19 AS | Real estate | 2022 |
| Mement AS | Information & communication | 2004 |
| MFB Holding AS | | 2025 |
| MGJ AS | | 2021 |
| Mik Holding AS | Construction | 2018 |
| Mikrodesign AS | Construction | 2023 |
| Min Reklamasjon AS | Professional & scientific | 2025 |
| Mindblowing Music Mme AS | Professional & scientific | 2017 |
| Mingus Invest AS | Real estate | 2005 |
| Misa Invest AS | | 2025 |
| Mister Lda V/ Byrået I Son AS | Construction | 2005 |
| Mjelve Konsult AS | Information & communication | 2017 |
| ML Utvikling AS | Professional & scientific | 2014 |
| Mme Holding AS | Real estate | 2016 |
| Mo Knausen AS | Wholesale & retail | 2005 |
| Molthe Invest AS | Administrative & support | 2005 |
| Mona Nordby Holding AS | Financial services | 2005 |
| Monica Heck AS | Professional & scientific | 2012 |
| Mono Yacht AS | Manufacturing | 2017 |