| Maksimal AS | Oslo | 2021 |
| Maksimal Coaching AS | Oslo | 2024 |
| Maleglede AS | Asker | 2021 |
| Malimo AS | Steinkjer | 2017 |
| Malimo AS | Steinkjer | 2024 |
| Malins Helsereise AS | Oslo | 2024 |
| Malins Helsereise Holding AS | Oslo | 2024 |
| Maliregina Da | Trysil | 2015 |
| Malmklumpen Barnehage SA | Narvik | 1989 |
| Malosalg AS | Oslo | 2021 |
| Malvik Trafikkskole AS | Vikhammer | 2000 |
| Malvik Undervisning Trafikkskole AS | Jessheim | 2022 |
| Mama Purity AS | Moss | 2020 |
| Mamma Mia Barnehage AS | Kløfta | 2008 |
| Mammaharmoni AS | Sandefjord | 2025 |
| Mammamestring AS | Sandnes | 2025 |
| Management Partner AS | Moelv | 1985 |
| Management Synergy AS | Tønsberg | 2009 |
| Mangelberget Barnehage SA | Oslo | 1990 |
| Mangfolk AS | Bolstadøyri | 2021 |
| Mara Coaching AS | Høvik | 2008 |
| Marco Elsafadi AS | Bønes | 2011 |
| Maren Erdvik AS | Kristiansand S | 2019 |
| Margit Olsvik AS | Kristiansand S | 2024 |
| Margo Olavesen AS | Rasta | 2024 |
| Margrethe Janbu Dressage AS | Askim | 2019 |
| Margrethe Otto Skar AS | Drammen | 2023 |
| Mari Naturbarnehage SA | Ytre Enebakk | 2003 |
| Mariann Eikelia AS | Stabbestad | 2024 |
| Mariannes Hus AS | Oslo | 2022 |
| Maridalen Barnehage SA | Oslo | 1984 |
| Marie Louise Tank AS | Oslo | 2004 |
| Marie Melania AS | Oslo | 2021 |
| Marieke Anna AS | Skaland | 2025 |
| Marielas Fitness AS | Drøbak | 2013 |
| Marihøna Barnehage SA | Sandvika | 1993 |
| Marihøna Barnehage SA | Gjøvik | 1990 |
| Marihøna Gårds- Og Friluftsbarnehage AS | Furnes | 2016 |
| Marina Malgina AS | Oslo | 2023 |
| Marina Wedenberg AS | Geilo | 2008 |
| Marine Seajoy Da | Namsos | 2025 |
| Marisafe AS | Ålesund | 2024 |
| Marisletta Barnehage SA | Steinkjer | 1989 |
| Maristua Barnehage SA | Hakadal | 1982 |
| Marit Gaare Laache AS | Bekkestua | 2024 |
| Marita Hunder AS | Vingelen | 2014 |
| Marita Ross AS | Hundvåg | 2024 |
| Maritim Kompetanse Sørlandet AS | Kristiansand S | 2025 |
| Maritim Sjøbemanning AS | Kaldfarnes | 2023 |
| Maritim Utdanning AS | Tønsberg | 2017 |
| Maritime Medicine AS | Rådal | 2021 |
| Marius Trafikkskole AS | Mogreina | 2022 |
| Markabygda Montessoriskole SA | Markabygda | 2003 |
| Markaplassen Barnehage SA | Ranheim | 1992 |
| Markedsføringsforeningen I Oslo Drift AS | Oslo | 2002 |
| Markestad AS | Ingeberg | 2013 |
| Markomp AS | Oteren | 2024 |
| Marnar Trafikkskole AS | Mandal | 2020 |
| Marops AS | Moss | 2023 |
| Marshmallow Invest AS | Stabekk | 2022 |
| Marte Dreier Audiopedagog AS | Lillestrøm | 2018 |
| Martens Consulting AS | Duken | 2002 |
| Marthe Strædet Babysvømming AS | Kristiansand S | 2014 |
| Marthe Vadders Rideskole AS | Ålesund | 2023 |
| Martin Gabrielsen Invest AS | Oslo | 2016 |
| Martina AS | Søndeled | 1996 |
| Marum Trafikkskole AS | Kolsås | 2015 |
| Marvik Kompetanse AS | Ombo | 2024 |
| Mash Studios Gamlebyen AS | Oslo | 2020 |
| Mash Universe AS | Oslo | 2021 |
| Mashti Community AS | Oslo | 2024 |
| Maskin Og Kran Opplæring AS | Narvik | 2013 |
| Maskin Og Truckopplæring AS | Moss | 2014 |
| Maskinkurs AS | Fyllingsdalen | 2003 |
| Maskinopplæring AS | Vestnes | 2013 |
| Maskinopplæring Øst AS | Moelv | 2012 |
| Mass Competence Consult AS | Husøysund | 2025 |
| Master Management Norge AS | Oslo | 2002 |
| Master on Consulting AS | Jessheim | 2022 |
| Master Sheff AS | Sylling | 2020 |
| Master Trafikkskole AS | Sandvika | 2025 |
| Masterment AS | Sandefjord | 2021 |
| Mat Og Trening Sandnes AS | Sandnes | 2024 |
| Mat Å Sånn AS | Sveio | 2026 |
| Mata Leon AS | Kolbotn | 2023 |
| Matast AS | Lillehammer | 2022 |
| Matematikk AS | Hønefoss | 2020 |
| Mathilde Junge AS | Stord | 2024 |
| Mathildebekken Barnehage SA | Nesna | 1992 |
| Matilda AS | Limingen | 2013 |
| Matilda Egra AS | Grimstad | 2022 |
| Matilda Strømsbu AS | Arendal | 2022 |
| Matmentor AS | Orkanger | 2020 |
| Matte.No AS | Oslo | 2025 |
| MATTE100 AS | Oslo | 2017 |
| Matteglød AS | Larvik | 2020 |
| Mattehelten AS | Kristiansand S | 2024 |
| Mattehuset AS | Oslo | 2018 |
| Mattemagi AS | Stjørdal | 2026 |
| Matterix Skole AS | Grimstad | 2021 |