| Ina Haugen AS | Health & social care | 2022 |
| Inesplo AS | Education | 2022 |
| Ingebrigtsli Holding AS | | 2020 |
| Innerski AS | Professional & scientific | 2025 |
| Interiør Line AS | Wholesale & retail | 2021 |
| Invest by Blom AS | | 2025 |
| Irs Invest AS | Real estate | 2019 |
| Isam Holding AS | Financial services | 2016 |
| Iskoglund Invest AS | Wholesale & retail | 2019 |
| Ixcelio AS | Information & communication | 2016 |
| J.Morgan Invest AS | | 2014 |
| Jag & Vi AS | Professional & scientific | 2006 |
| Jaktvald 2A I Nittedal SA | Agriculture & fishing | 2021 |
| Je Jensen Holding AS | | 2016 |
| Jomaleli Holding AS | | 2021 |
| K Borkmo Holding AS | | 2025 |
| Kafe Nybrent AS | Hospitality | 2024 |
| Ke-Thomassen Holding AS | | 2023 |
| KFG Holding AS | Construction | 2007 |
| Kin Health AS | Information & communication | 2025 |
| Kjbc AS | Information & communication | 2006 |
| Kjbc Maskin AS | Construction | 2011 |
| Kjul Handel AS | Real estate | 2011 |
| Kjulsveien 15 AS | Real estate | 2006 |
| Kkfuskeland AS | Education | 2024 |
| Klubbsport AS | Wholesale & retail | 2019 |
| Knut Nystad AS | Education | 2016 |
| Koia Soft Norway AS | Information & communication | 2018 |
| Konstant Holding AS | | 2025 |
| KONTORASSISTENTEN Ans | | 1988 |
| Kribe AS | Real estate | 2007 |
| Krihan Invest AS | | 2013 |
| Kristiansen Renhold AS | Administrative & support | 2026 |
| Kristines Hud Og Kroppspleie AS | Other services | 2016 |
| Krohn Sellin Holding AS | Hospitality | 2021 |
| Kruttverket Fus Barnehage AS | Education | 2019 |
| Krøll Eiendom AS | Real estate | 2018 |
| KSN Nittedal AS | | 2024 |
| Kvist Marketing AS | Professional & scientific | 2025 |
| Kvitfjellhytta Nuf | Real estate | 2006 |
| La Chasse AS | Real estate | 2014 |
| La'Santino Holding AS | | 2026 |
| Laa Perla AS | Hospitality | 2024 |
| Labre AS | | 2022 |
| Lakeview Management AS | Information & communication | 2014 |
| Lambda Digital Nuf | Information & communication | 2020 |
| Lamøy Invest AS | | 2024 |
| Laursen Invest AS | Financial services | 2014 |
| Lederrådgivning AS | Education | 2014 |
| Linneas Hage AS | Wholesale & retail | 2019 |
| Little Dude Invest AS | | 2023 |
| Livv Health AS | Information & communication | 2023 |
| LKT AS | Hospitality | 2019 |
| Lunda AS | Wholesale & retail | 2025 |
| Lykke Hud & Spa AS | Other services | 2008 |
| Lyng Holding AS | | 2024 |
| Løvlie AS | Construction | 2004 |
| M.T.G AS | Arts & recreation | 2021 |
| Made by Blom AS | Information & communication | 2025 |
| Mads Hexeberg AS | | 2015 |
| Mae Entreprenør AS | Construction | 2022 |
| Magneter & Verktøy AS | Wholesale & retail | 2003 |
| Mahø AS | Real estate | 2005 |
| Mailgraph Eiendom AS | Real estate | 1995 |
| Makado Holding AS | | 2019 |
| Maling Og Bygganlegg Lindstrøm | Construction | 2000 |
| Manepe AS | Information & communication | 2019 |
| Marineservice Oslo AS | Manufacturing | 2021 |
| Martin Jarnæs Nilsen AS | Construction | 1997 |
| Mediehuset Varingen AS | Information & communication | 2017 |
| Meginhufr AS | Information & communication | 2026 |
| Metronyx Nordic AS | Wholesale & retail | 2026 |
| Microsystem AS | Professional & scientific | 2022 |
| Millionish Media AS | Professional & scientific | 2022 |
| Mimmi AS | | 1957 |
| Minde-S AS | Construction | 2025 |
| Minmar AS | Real estate | 2007 |
| Miui AS | Health & social care | 2024 |
| MJ Future AS | | 2025 |
| MJS AS | Construction | 2019 |
| MJS Bygg AS | Construction | 2025 |
| Mjøsen Eiendom AS | Real estate | 2005 |
| Mo Eiendom Nittedal AS | Real estate | 2018 |
| Mo Gård AS | | 2025 |
| Mo Holding Nittedal AS | Hospitality | 2019 |
| Moderne Boligutvikling AS | Real estate | 2012 |
| Molncom AS | Professional & scientific | 2015 |
| Moltzow AS | | 2019 |
| Mostua AS | Real estate | 2026 |
| Mostua Entrepenør Og Holding AS | | 2019 |
| Mosø Holding AS | | 2019 |
| Movimento AS | Professional & scientific | 2022 |
| MSS Logistikk AS | Transport & logistics | 2026 |
| Mumble AS | Information & communication | 2021 |
| Mwpf Holdings AS | | 2020 |
| My Drive AS | Transport & logistics | 2025 |
| Myco Group AS | Manufacturing | 2025 |
| Myhre Lås- Og Mek Verksted AS | Manufacturing | 1986 |
| Myrens Nittedal AS | Arts & recreation | 2020 |
| Måsabjønn AS | | 2024 |