| J.N Invest AS | | 2021 |
| Ja-Ha Holding AS | | 2019 |
| Jack Sushi & Asia Mat AS | Hospitality | 2017 |
| Jadar Eiendom AS | Real estate | 1998 |
| Jaija AS | Professional & scientific | 2008 |
| Jay-Jay AS | Professional & scientific | 2009 |
| JB Consultants AS | Administrative & support | 2013 |
| Jb-Holding AS | Professional & scientific | 2010 |
| Jekri Finans AS | Financial services | 2007 |
| Jekri Forvaltning AS | Professional & scientific | 2017 |
| Jeo Finans AS | Financial services | 2015 |
| JHM Holding AS | Financial services | 2014 |
| JK Investering AS | | 2020 |
| JNG Invest AS | Real estate | 2021 |
| Joran Holding AS | Real estate | 2014 |
| Jotag AS | | 2026 |
| JP Engineering AS | Professional & scientific | 2025 |
| JRP Eiendom AS | Real estate | 2005 |
| JS Montasje Og Vedlikehold AS | Construction | 2024 |
| Jungmann AS | | 2019 |
| K. Fosmark AS | | 2023 |
| K. Kloster & Sønner AS | Professional & scientific | 2025 |
| Kaada AS | Real estate | 1990 |
| Kaja Stokstad Holding AS | Real estate | 2019 |
| Kampe AS | | 2020 |
| Kapitalvekst AS | | 2025 |
| KARLS1 Holding AS | | 2013 |
| Keharo AS | Health & social care | 2020 |
| Kenneth Jensen Holding AS | Financial services | 2016 |
| Kes Holding AS | Manufacturing | 2022 |
| Kessa AS | Real estate | 2014 |
| Kessa Eiendom AS | Real estate | 2016 |
| KH Kapital AS | Financial services | 2012 |
| Kick Holding AS | Real estate | 2010 |
| Kilenot AS | | 2020 |
| Kiropraktor Silje Kristensen AS | Health & social care | 2022 |
| Kisteneset Holding AS | Real estate | 2021 |
| Kjela AS | | 2025 |
| Kjen AS | Professional & scientific | 2008 |
| Klippenberg Invest AS | Education | 2023 |
| Knutzen Consultant AS | Professional & scientific | 2020 |
| Kokken I Logen AS | Hospitality | 2024 |
| Kongslien Petrophysics AS | Mining & quarrying | 2017 |
| Konviti AS | Financial services | 2013 |
| Kpenterprise AS | Professional & scientific | 2017 |
| KR Stjern Holding AS | | 2024 |
| Krosshaug Loen Velforening Ba | Other services | 2003 |
| Kund Holding AS | | 2022 |
| Kvam Data AS | Information & communication | 1987 |
| Lakr AS | | 2025 |
| LBV Holding AS | Financial services | 2015 |
| Lerke Holding AS | Real estate | 2014 |
| Lid Invest | Real estate | 2019 |
| Lien Finans AS | Administrative & support | 2012 |
| Lintact Holding AS | Information & communication | 2022 |
| Lintact Ltd Nuf | Information & communication | 2010 |
| Lintact Software Solutions AS | Information & communication | 2023 |
| List AS | | 2020 |
| Log Bygg AS | Construction | 2013 |
| Loham Invest AS | | 2024 |
| Longacre AS | Financial services | 2017 |
| Longacre I AS | | 2025 |
| Longfield AS | Manufacturing | 2013 |
| Longfield Holding AS | Manufacturing | 2017 |
| Longfield Invest I AS | Financial services | 2016 |
| Longfield Invest II AS | | 2025 |
| Lundefuglen AS | Professional & scientific | 2023 |
| Lærerskolen AS | Education | 2012 |
| M.M Utvikling AS | Real estate | 2020 |
| M.Ø.B AS | | 2026 |
| Majo Kapital AS | | 2026 |
| Malurd AS | | 2020 |
| Mapsi Design AS | Professional & scientific | 2021 |
| Mapsi Holding AS | Real estate | 2017 |
| Marita Ross AS | Education | 2024 |
| Marwin Rådgivning AS | Professional & scientific | 2011 |
| Masito AS | Construction | 1976 |
| Mccabe Holding AS | | 2022 |
| Mcom Holding AS | | 2016 |
| Medina Consulting AS | Professional & scientific | 2016 |
| Meed AS | Administrative & support | 2025 |
| Melanir Holding AS | | 2025 |
| Melis Eiendom AS | Wholesale & retail | 1995 |
| Memosika AS | Financial services | 2005 |
| Micronord AS | Information & communication | 2012 |
| Midtskips AS | Professional & scientific | 2021 |
| Miggie Syre AS | Professional & scientific | 2026 |
| Miglia AS | Professional & scientific | 2004 |
| Miglia Consulting AS | Professional & scientific | 2018 |
| Millibar Capital AS | | 2023 |
| Millibar Holding AS | | 2023 |
| Mirum AS | | 2021 |
| Mjølner-Bygg AS | Construction | 2018 |
| MKT AS | Professional & scientific | 2012 |
| Moan Holding AS | Financial services | 2020 |
| Monsvik Eiendom AS | Real estate | 2024 |
| Monsvik Holding AS | | 2024 |
| Mopato AS | Wholesale & retail | 2019 |
| Morning Jacket Invest AS | | 2026 |
| Multicad AS | Information & communication | 2003 |