| Longumkrysset Utvikling AS | Real estate | 2020 |
| Lossene Invest AS | | 2024 |
| LOTUS1 AS | | 2023 |
| LPG Arendal AS | Wholesale & retail | 2017 |
| LPG Kristiansand AS | Wholesale & retail | 2020 |
| LS Eiendom AS | Real estate | 2014 |
| LT Eiendom 1 AS | Real estate | 2024 |
| Lubba AS | | 2018 |
| Lucky 4 Holding AS | | 2025 |
| Lucky Frisør Amfi Arendal AS | Other services | 2004 |
| Lucky Frisør AS | Other services | 1996 |
| Lucky Frisør Harebakken AS | Other services | 2005 |
| Lucky Frisør Maxis AS | Other services | 2006 |
| Lucky Frisør Stoa AS | Other services | 1999 |
| Lund På Lund AS | Wholesale & retail | 2022 |
| Lundseng Holding AS | Wholesale & retail | 2021 |
| Lundvall AS | Wholesale & retail | 2026 |
| Lundvall Dagligvare AS | Wholesale & retail | 2019 |
| Lychebod AS | | 2025 |
| Lys Omsorg Arendal AS | Health & social care | 2024 |
| Lysaker Helse Og Omsorg AS | Health & social care | 2025 |
| Madam Reiersen AS | Hospitality | 1991 |
| Magasinet AS | Information & communication | 2012 |
| Mage- Tarmklinikken AS | Health & social care | 2014 |
| Magenta Living AS | Real estate | 1992 |
| Magenta Minilager AS | Real estate | 2018 |
| Magnussen Transport & Logistikk AS | Transport & logistics | 2013 |
| Make Invest AS | | 2015 |
| Malcan AS | Real estate | 1999 |
| Maler Lars Hinge AS | Construction | 2014 |
| Malermester Gundersen AS | Construction | 2007 |
| Malmbryggen 1 AS | Real estate | 2021 |
| Malming Consulting AS | Information & communication | 2022 |
| Manuellterapeut Am. Meyer-Myklestad AS | Health & social care | 2020 |
| Marcin Wysocki Holding AS | Financial services | 2012 |
| Marcussen Eiendom AS | Real estate | 2019 |
| Marcussen Invest AS | Wholesale & retail | 2023 |
| Marcussen Ur & Smykker AS | Wholesale & retail | 1987 |
| Mare Holding AS | Health & social care | 2005 |
| Marina Yacht Club Arendal AS | Hospitality | 2024 |
| Marine & Cargo Independent Inspection Services AS | Professional & scientific | 2024 |
| Maritim AS | Administrative & support | 2000 |
| Maritime Universal Service Nuf | Professional & scientific | 2011 |
| Marius Interiør AS | Construction | 2020 |
| Markedshjelpen AS | Professional & scientific | 2015 |
| Markedshjelpen Holding AS | | 2021 |
| Markens Goder Ans | Wholesale & retail | 1992 |
| Marketing Sør Fritzen Og Fritzen Ans | Wholesale & retail | 1987 |
| Markus Invest AS | Real estate | 2024 |
| Martin Breivik AS | Information & communication | 1987 |
| Martinshus AS | Administrative & support | 2011 |
| Master Bil AS | Other services | 2018 |
| Masyv Invest AS | | 2021 |
| Masø Holding AS | | 2019 |
| Mat&Mer AS | Hospitality | 2023 |
| Match Rekruttering & Bemanning AS | Professional & scientific | 2022 |
| Matilda Strømsbu AS | Education | 2022 |
| Mauritz Johnsen Holding AS | | 1983 |
| Max Effect AS | Professional & scientific | 2014 |
| Max Security AS | Administrative & support | 2016 |
| Maximal AS | Real estate | 2015 |
| Maxis Eiendom AS | | 2025 |
| Maxis Legesenter AS | Health & social care | 2015 |
| MB Stålbygg AS | Real estate | 2014 |
| Mba Auto AS | Wholesale & retail | 2026 |
| MBP Invest AS | | 2024 |
| Mcsn Holding AS | Hospitality | 2024 |
| Meccon AS | Manufacturing | 2015 |
| Medborgernes Menneskerettighets Kommisjon | Other services | 2001 |
| Media Service AS | Information & communication | 1983 |
| Media Sørlandet AS | Administrative & support | 2015 |
| Medicvision AS | Wholesale & retail | 2005 |
| Medicvision Optikk AS | Wholesale & retail | 2025 |
| Medinovo AS | Health & social care | 2014 |
| Mefa AS | | 2021 |
| Megaflis Agderparken AS | Wholesale & retail | 2004 |
| Meglerhuset & Partners AS | Real estate | 1999 |
| Meller AS | Wholesale & retail | 2018 |
| Merg Fysioterapi AS | Health & social care | 2026 |
| Mermaids Beyond AS | Professional & scientific | 2024 |
| Meshtech AS | Information & communication | 2012 |
| Mette & Kameratene Karlsen Andersen Og Karlsen Ans | Arts & recreation | 2000 |
| Meyer Norschau Design AS | Professional & scientific | 2012 |
| MFB Anlegg AS | Construction | 2021 |
| MHG Invest AS | | 2021 |
| Mi to Frisør AS | Other services | 1998 |
| Mickaco AS | | 2024 |
| Midtstøl AS | Real estate | 1966 |
| Midtstøl Bulk AS | Transport & logistics | 1999 |
| Midtstøl Invest AS | Real estate | 2006 |
| Midtstøl Næringspark AS | Real estate | 2020 |
| Midtstøl Transport AS | Transport & logistics | 1978 |
| Mijiti Gatekjøkken AS | Hospitality | 2025 |
| Mikarema AS | Professional & scientific | 2006 |
| Mikrobageriet AS | Manufacturing | 2016 |
| Mikrobageriet Krøgenes AS | Manufacturing | 2026 |
| Minlegevakt AS | Information & communication | 2013 |
| Mira Mare AS | Real estate | 2013 |
| Mira Mare Holding AS | Real estate | 2013 |
| Mira Sandås AS | Real estate | 2015 |