| Kiso Bolig AS | Real estate | 2023 |
| Kjedalen Drift AS | Wholesale & retail | 2021 |
| Kjell Tore Moe AS | Construction | 1996 |
| Kjærstad AS | Financial services | 2007 |
| Kjærstad Holding AS | | 2022 |
| Kjærstad Transport AS | Transport & logistics | 2004 |
| Klampenborg Invest AS | Real estate | 1993 |
| Knivsenter.No AS | Wholesale & retail | 2006 |
| Kodeg AS | | 2021 |
| Kofaterm Norge AS | Wholesale & retail | 2023 |
| Kogstad Mjølk AS | Agriculture & fishing | 2026 |
| Kogstadmjølk Da | Agriculture & fishing | 2007 |
| Kollywood Entertainment AS | Information & communication | 2022 |
| Kongsvinger Retail I AS | Real estate | 2013 |
| Kongsvinger Retail II AS | Real estate | 2013 |
| KP Service AS | Construction | 2008 |
| Kroghsgaard AS | Real estate | 2023 |
| Kronberg Holding AS | Professional & scientific | 2013 |
| KS Souko Hårprodukter | Wholesale & retail | 2001 |
| KTV Group Øst AS | Administrative & support | 2022 |
| Kuldemontørene AS | Construction | 2013 |
| Kunst Holding AS | Financial services | 2018 |
| Kvalitet VVS Entreprenør AS | Construction | 2019 |
| Kvernberg Invest AS | Construction | 2005 |
| Landkjenning AS | | 2026 |
| Langsholt Invest AS | Information & communication | 2022 |
| Langsholt Maskin Og Eiendom AS | Professional & scientific | 2020 |
| Langsholt Snø Og Grønt AS | Administrative & support | 2005 |
| Larapinta AS | Agriculture & fishing | 2021 |
| Lars Roar Fallrø AS | Real estate | 2013 |
| Leif Haugen Holding AS | Real estate | 2006 |
| Leira Regnskap SA | Professional & scientific | 2003 |
| Lema Bolig AS | Real estate | 2024 |
| Lemalou AS | Wholesale & retail | 2022 |
| Lian Byggkonsult AS | Professional & scientific | 2026 |
| Lillestrøm Bilverksted AS | Real estate | 1984 |
| Live Wire Concerts AS | Professional & scientific | 2020 |
| Livelight AS | Information & communication | 2025 |
| LJ Quantum AS | | 2021 |
| Ljungmann AS | Manufacturing | 2003 |
| Ljungmann Hellen AS | Real estate | 1988 |
| LM Bygg & Eiendomsservice AS | Real estate | 2023 |
| Lnstv Holding AS | | 2026 |
| Logistikkjentene AS | Professional & scientific | 2025 |
| Logistikkutvikling AS | Professional & scientific | 2015 |
| Lorentz Holding AS | | 2026 |
| Lorenzato Holding AS | Other services | 2024 |
| Lubben AS | Real estate | 2021 |
| Lundby Inv AS | | 2023 |
| Lykkehaven AS | Administrative & support | 2019 |
| Lyr AS | Education | 2021 |
| Løvberg Bygg Og Eiendom AS | Construction | 2014 |
| Løvberg Holding AS | Construction | 2014 |
| M Våge Invest AS | | 2026 |
| M-Media AS | | 2013 |
| M.M.7 Bygg AS | Construction | 2023 |
| M.M.7 Holding Invest AS | Construction | 2020 |
| M3 Entreprenør AS | Construction | 2024 |
| Magbo AS | Real estate | 2006 |
| Magnar Bore Holding AS | | 2025 |
| Majaka Invest AS | | 2022 |
| Majorveien 26-28 AS | Real estate | 2022 |
| Maler Snekker Waldemar AS | Construction | 2026 |
| Malerfirma Lasse Gundal AS | Construction | 2013 |
| Malervikarene Ans | Administrative & support | 2004 |
| Mapre AS | Construction | 2020 |
| Marduv AS | Information & communication | 2025 |
| Marketing Studio AS | Transport & logistics | 2024 |
| Masertek AS | Manufacturing | 2023 |
| Massets AS | | 2015 |
| Mathias Ruud Invest AS | | 2023 |
| Maurholet AS | | 2024 |
| MB DK Projects Nuf | Professional & scientific | 2025 |
| MB Kursiu Projektas Nuf | Professional & scientific | 2026 |
| MBM Saga Invest AS | | 2024 |
| MC Transport AS | Transport & logistics | 2019 |
| MC TRANSPORT1 AS | | 2025 |
| Mc-Power Da | Wholesale & retail | 2012 |
| Mel Gardermoen 32 AS | Real estate | 2021 |
| Mel Gardermoen 40 AS | Real estate | 2022 |
| Mel Gardermoen A9 AS | Real estate | 2021 |
| Membraner Og Taktekking AS | Construction | 1995 |
| Mende AS | Education | 2020 |
| Mes Fjeldstad Holding AS | | 2025 |
| Mfalkevik Holding AS | | 2025 |
| Miljøfôr Eiendom AS | Real estate | 2021 |
| Miljøtak AS | Construction | 1996 |
| Millamoni AS | | 2021 |
| Mimmis Blomster & Interiør AS | Wholesale & retail | 2012 |
| Min-Takst AS | Real estate | 2025 |
| Minken Consulting AS | Professional & scientific | 2024 |
| Minken Eiendomsservice AS | Administrative & support | 2026 |
| Minken Holding AS | Financial services | 2017 |
| Mistical Studios AS | Information & communication | 2025 |
| Mjølkerampa AS | Health & social care | 2002 |
| Mjølkerampa Tiltak AS | Health & social care | 2024 |
| Mjølkerampa Tjenester AS | Health & social care | 2024 |
| MKM Group AS | Construction | 2023 |
| Mo-Lo Holding AS | | 2025 |
| Mollan Holding AS | | 2025 |