| Komplett Byggteknikk AS | Construction | 2020 |
| Komplett VVK AS | Construction | 2023 |
| Konvex AS | Information & communication | 2008 |
| Kornsilovegen 84 AS | Real estate | 2019 |
| Kreativ Partner AS | Professional & scientific | 2019 |
| Kreative Krefter AS | Health & social care | 2006 |
| KS Kolbotn Trelast Sundt & Co | Real estate | 1947 |
| Kuboå AS | Information & communication | 2013 |
| Kullebund Eiendom AS | Real estate | 2016 |
| Kullebund Gård AS | Real estate | 2007 |
| Kullebunden Spiseri AS | Hospitality | 2013 |
| Kunter AS | Real estate | 2010 |
| Kurlandsåsen 2 Eiendom AS | Real estate | 2012 |
| Kurås Holding AS | Wholesale & retail | 2024 |
| Kvernaas Arkitekter AS | Professional & scientific | 1994 |
| Kwa Invest AS | | 2023 |
| L Haug Holding AS | | 2023 |
| La Casa Invest AS | Financial services | 2005 |
| Lag Verksted AS | Other services | 2025 |
| Lagoleg AS | Health & social care | 1988 |
| Lamo AS | Real estate | 1986 |
| Landfjord Ans | Administrative & support | 2000 |
| Lars Gravermoen AS | Construction | 1992 |
| Laruan AS | Professional & scientific | 2009 |
| LCM Grafisk AS | Professional & scientific | 2018 |
| Le Petit AS | Wholesale & retail | 2025 |
| Leks Holding AS | | 2024 |
| Lemma Plus AS | Information & communication | 2024 |
| Lignum AS | Wholesale & retail | 2021 |
| Line Torp AS | Professional & scientific | 2026 |
| Liphe AS | Professional & scientific | 2001 |
| Livora AS | Health & social care | 2026 |
| LNR Mother AS | | 2026 |
| Loeshagen Holding AS | | 2018 |
| Los Balcones AS | Real estate | 2014 |
| Losol AS | Professional & scientific | 2014 |
| Lovisenberggata 3 AS | Real estate | 1936 |
| LST Revisjon AS | Professional & scientific | 2018 |
| Ludimus AS | | 2024 |
| Lumen Installasjon AS | Construction | 2016 |
| Lundin Holding AS | Financial services | 2012 |
| Lup Eiendom AS | Real estate | 2019 |
| LWK Invest AS | Real estate | 2015 |
| Lysaker Capital AS | Real estate | 2007 |
| Lysk AS | Professional & scientific | 2015 |
| Lyskestrekk Records AS | Information & communication | 2024 |
| Løitegaard Invest AS | | 2022 |
| Lønnerhagen AS | Real estate | 2013 |
| Løvenstadtorget 12 Eiendom AS | Wholesale & retail | 2012 |
| Madhu Holding AS | | 2012 |
| Mafica Finans AS | Financial services | 2007 |
| Magic Pixels Da | Information & communication | 2003 |
| Magikon Forlag Ans | Information & communication | 2007 |
| Make Hay AS | Professional & scientific | 2023 |
| Maketronics AS | Information & communication | 2007 |
| Mally-Vally AS | Manufacturing | 2015 |
| Managementmill AS | Professional & scientific | 2007 |
| Mandarin AS | Information & communication | 2023 |
| Mapa Lekekafé AS | Arts & recreation | 2026 |
| Maren Kvalvaag AS | Health & social care | 2023 |
| Maria Q Holding AS | | 2025 |
| Marius Ruud Invest AS | | 2017 |
| Markussen Invest AS | Real estate | 1996 |
| Maskin Og Miljø AS | Wholesale & retail | 2020 |
| Mata Leon AS | Education | 2023 |
| Maxtrykk AS | Arts & recreation | 2024 |
| Mediebyrået Enklere Valg AS | Professional & scientific | 2018 |
| Medon AS | Information & communication | 2020 |
| MG Consult AS | Wholesale & retail | 2015 |
| Mich AS | | 2026 |
| Midtoddveien 2 Eiendom AS | Real estate | 2012 |
| Mikael Samuelsen AS | Information & communication | 2025 |
| Mikrobe AS | Wholesale & retail | 2024 |
| Mlpf Holding AS | Professional & scientific | 2017 |
| Modahl Elektriske AS | Construction | 2019 |
| Modahl Holding AS | | 2019 |
| Momo Holding AS | Professional & scientific | 2011 |
| Morwen AS | Financial services | 2012 |
| Motogruppen AS | Wholesale & retail | 2023 |
| Motoi AS | Professional & scientific | 2014 |
| Mozzani AS | | 2020 |
| MPK Invest AS | | 2002 |
| Munkerudkleiva Eiendomsutvikling AS | Real estate | 2025 |
| Muskler, Mat Og Mening AS | Education | 2019 |
| Muspel AS | Professional & scientific | 2026 |
| MX3.NO AS | Health & social care | 2018 |
| Myrvoll Eiendomsforvaltning AS | Real estate | 2020 |
| Nebbiolo Capital AS | Financial services | 2019 |
| Nekromantheon Da | Arts & recreation | 2012 |
| Nema Holding AS | Wholesale & retail | 2021 |
| Nerland Holding AS | Construction | 2019 |
| Netcentric Systems AS | Information & communication | 1996 |
| Netkem AS | Wholesale & retail | 2001 |
| Nettec AS | Wholesale & retail | 1985 |
| Newbie AS | Real estate | 1973 |
| Nijjer Holding AS | Health & social care | 2021 |
| Nilselia Vel Va-Prosjekt Vaset SA | Water & waste | 2010 |
| Nina Ruthenbeck Moen AS | | 2024 |
| Niss Invest AS | Financial services | 2014 |
| NLP Huset AS | Health & social care | 2007 |