| Mjøsen Bygg Og Eiendom Ans | Real estate | 2003 |
| Mjøsen Bygg Og Eiendom AS | Construction | 1998 |
| Mjøsgårdene SA | Other services | 2007 |
| Mjøshagen Holding AS | | 2022 |
| Mjøshus AS | Construction | 2019 |
| Mjøsparken AS | Real estate | 2011 |
| Mjøsporten Eiendom AS | Real estate | 1983 |
| Mjøsskigard AS | Manufacturing | 2021 |
| Mjøstre AS | Wholesale & retail | 2012 |
| Mjøstruck Da | Manufacturing | 2002 |
| MK Development AS | | 2017 |
| MK Forvaltning AS | | 2022 |
| MLR Hodl AS | Wholesale & retail | 2024 |
| MNH Invest AS | | 2026 |
| Mno Agentur AS | Wholesale & retail | 2022 |
| Moelven Langmoen AS | Manufacturing | 2000 |
| Moja Holding AS | Financial services | 2017 |
| Monopol AS | Real estate | 2020 |
| Morgrethe AS | | 2009 |
| Morten Skaug Brazil.No AS | Information & communication | 2013 |
| Morten Tømrer AS | Construction | 2005 |
| Mortens Kranservice AS | Construction | 2022 |
| Movit AS | Professional & scientific | 2021 |
| MS Brumunddal Bygg, Biloutlet Og Bilutleie AS | Construction | 2015 |
| MS Eiendomsutvikling AS | Real estate | 2014 |
| MSK Utleie AS | Real estate | 2010 |
| Multi Bygg AS | Construction | 1977 |
| Murer S. Skansberg AS | Construction | 2023 |
| Murer Tore Granmo AS | Construction | 2018 |
| Murerfirma Kjell Syversen AS | Construction | 2000 |
| Muskel Og Ledd AS | Health & social care | 2025 |
| Mustang Invest AS | Other services | 2005 |
| Myldre AS | | 2022 |
| Mølla Grønt Og Godt Da | Wholesale & retail | 2010 |
| Mølle Strand AS | Real estate | 2012 |
| Mørkvedtunet AS | Real estate | 2013 |
| Natalie Hage AS | Health & social care | 2022 |
| Natalie Hage Holding AS | Health & social care | 2022 |
| ND Holding AS | | 2022 |
| Neste Fase AS | Administrative & support | 2026 |
| Newbiegainzz AS | | 2023 |
| NF Maskin AS | Administrative & support | 2021 |
| Niclas Berntsen Invest AS | Financial services | 2015 |
| Noahs Ark Samdrift Da | Agriculture & fishing | 2009 |
| Noahs Invest AS | | 2025 |
| Nobel Innlandet Holding AS | Wholesale & retail | 2023 |
| Nord Overnatting AS | Real estate | 2022 |
| Nordal R AS | Construction | 2025 |
| Nordic Heat Solution AS | Energy | 2024 |
| Nordic Prosjekt AS | Real estate | 2025 |
| Nordisk Heste- Og Hundeterapiskole AS | Agriculture & fishing | 2015 |
| Nordsveen Eiendom AS | Real estate | 1975 |
| Nordsveen Invest AS | Real estate | 2016 |
| Nordsveen VVS AS | Real estate | 2023 |
| Nordåsveien Plantesenter AS | Wholesale & retail | 1991 |
| Norest Bygg AS | Construction | 2013 |
| Norgesgruppen Innland AS | Wholesale & retail | 2001 |
| Norgesgruppen Regnskap AS | Professional & scientific | 2001 |
| Norgym AS | Arts & recreation | 2023 |
| Norheat AS | Construction | 2016 |
| Norheat Eiendom AS | Construction | 2016 |
| Norsk Brønnboring AS | Construction | 2019 |
| Norsk Filmbyrå AS | Professional & scientific | 1996 |
| Norsk Hundeterapi AS | Other services | 2019 |
| Norsk Kulde Og Varme AS | Wholesale & retail | 2017 |
| Norsk Regnskap AS | Professional & scientific | 2024 |
| Norstad Maskin AS | Wholesale & retail | 2006 |
| Norwegian Eiendom AS | Real estate | 2016 |
| Norwegian Wood Cluster SA | Professional & scientific | 2017 |
| Norwy AS | Real estate | 1997 |
| Novaventure AS | | 2024 |
| Nybakken Eiendom AS | Real estate | 2025 |
| Nygata 12 AS | Real estate | 2013 |
| Nygata 13 Utvikling AS | Real estate | 2014 |
| Nygata Uteliv AS | Hospitality | 2019 |
| Nyvi AS | Professional & scientific | 2020 |
| Næringsparken Eiendom AS | Real estate | 2021 |
| O,M Holding AS | | 2025 |
| Oddpod Holding AS | Information & communication | 2020 |
| Odin VVS AS | Construction | 2024 |
| Oh Invest AS | Real estate | 2005 |
| Olav Grøttum Holding AS | Financial services | 2018 |
| Olav Hovde AS | Construction | 2005 |
| Ole Pedersen Tangen Invest AS | | 2023 |
| Omsted Holding AS | | 2025 |
| Omsted Invest AS | | 2025 |
| Oplandske Konserves Eiendom AS | Real estate | 2004 |
| Oppland Bilvask AS | Other services | 2007 |
| Orion Hamar AS | Real estate | 2013 |
| Oslo Bolig Og Næringsutvikling AS | Real estate | 2016 |
| Oson AS | Transport & logistics | 2023 |
| P & T Snekkerserivce AS | Construction | 2005 |
| Paf Eiendom AS | Construction | 2014 |
| Pag Holding AS | | 2021 |
| Parkettpartner AS | Construction | 1997 |
| Parkgata 16 AS | Real estate | 2007 |
| Parkgata 16 Holding AS | Real estate | 2023 |
| Parkgården 1 AS | Real estate | 2005 |
| Passasjen AS | Real estate | 1998 |
| Pedersen Eiendom AS | Real estate | 1995 |