| Mopeh AS | Real estate | 1993 |
| Mor Vangen AS | Real estate | 2023 |
| Morgenstierne AS | Professional & scientific | 2024 |
| Mostranda Camping AS | Hospitality | 2013 |
| Mov-Pro AS | Professional & scientific | 2011 |
| Moveien Vann- Og Avløpslag SA | Water & waste | 2017 |
| MRG AS | Administrative & support | 2025 |
| Msi Auto AS | Administrative & support | 2014 |
| Msi Invest AS | Administrative & support | 2005 |
| Museumsgata 41 AS | Real estate | 2010 |
| Musikkbritt AS | Education | 2014 |
| Musikkforvalterne AS | Information & communication | 2024 |
| Mågerø Opplag Og Båtservice AS | Manufacturing | 2007 |
| Mågerø Verft AS | Real estate | 1960 |
| Nesskogen Idrettspark AS | Real estate | 2007 |
| Net Zero Plastic AS | Professional & scientific | 2023 |
| NFH 250751 AS | Other services | 2025 |
| Nordic Financial Holding Ltd Nuf | Financial services | 2006 |
| Nordisk Metallramme System AS | Construction | 2023 |
| Normann Investeringsselskap AS | | 2005 |
| Norske Båt- Og Biltrekk AS | Manufacturing | 1995 |
| Næring-Bygg Entreprenør AS | Construction | 1996 |
| Odden Småbåthavn AS | Arts & recreation | 1990 |
| Omega Finans AS | Professional & scientific | 2012 |
| Omihus AS | Real estate | 1993 |
| Origo C AS | | 2025 |
| Oslo Byggfornyelse AS | Construction | 2007 |
| PHH Holding AS | Wholesale & retail | 2022 |
| Planet Bounty AS | Professional & scientific | 2019 |
| Pletly AS | Information & communication | 2021 |
| Polka II AS | | 2025 |
| Pour AS | Hospitality | 2019 |
| Present Moment AS | Administrative & support | 2014 |
| Ramdal Gård AS | Real estate | 1992 |
| Rammdak AS | Professional & scientific | 2021 |
| RD Servicepartner AS | Administrative & support | 2012 |
| Real Estate AS | Real estate | 1994 |
| Ren Fasadevask AS | Administrative & support | 2021 |
| Ren Vekst AS | Professional & scientific | 2024 |
| Rennemo Treverksted AS | Construction | 2025 |
| Riberia AS | Real estate | 2017 |
| Richard Investeringsselskap AS | | 2005 |
| Rå Sushi AS | Hospitality | 2022 |
| Rød Golf AS | Arts & recreation | 1989 |
| Røed Telecom AS | Construction | 2023 |
| Sam Eydes Gate 63 AS | Real estate | 2025 |
| Sandi Active AS | Wholesale & retail | 2024 |
| Sandwiki AS | Wholesale & retail | 2021 |
| Scan-Sense Eiendom AS | Real estate | 2004 |
| Scanbas Professional AS | Manufacturing | 2023 |
| Scanbase AS | Professional & scientific | 2002 |
| Scancatch AS | Wholesale & retail | 2002 |
| Scanmar Professional AS | Manufacturing | 2015 |
| Scanmar Ultimate AS | Professional & scientific | 2015 |
| Scantech Innovations AS | Professional & scientific | 2015 |
| Scantech Inventions AS | Professional & scientific | 2002 |
| Scantrawl AS | Professional & scientific | 2015 |
| Seahorse Eiendom AS | Real estate | 2010 |
| Seilerberget AS | Real estate | 2020 |
| Senterdekor AS | Manufacturing | 2008 |
| Senterlys AS | Wholesale & retail | 2013 |
| Sjøkrepsen AS | Agriculture & fishing | 2016 |
| Sk-I AS | | 2015 |
| Skafferiet Tjøme AS | Hospitality | 2013 |
| Skauen Treverksted AS | Manufacturing | 2020 |
| Skontorp Holding AS | Manufacturing | 2005 |
| Skriftgransker Reidun Wilhelmsen AS | Administrative & support | 2014 |
| Skybert-Tjenesten AS | Health & social care | 2025 |
| Snowbird AS | Real estate | 2004 |
| Solberg Mat AS | Wholesale & retail | 2004 |
| Somersholm AS | Wholesale & retail | 2017 |
| Stag AS | Administrative & support | 2016 |
| Stag Vedlikehold AS | Administrative & support | 2019 |
| Star Solutions AS | Manufacturing | 2021 |
| Starport AS | | 1997 |
| Steen Hanssen Invest AS | Financial services | 2013 |
| Stingfisher Powerboats AS | Manufacturing | 1993 |
| Stor-Re Consulting AS | Administrative & support | 2013 |
| Sttv Holding AS | | 2023 |
| Sundene Spillvannsanlegg SA | Water & waste | 2009 |
| Sunk Cost AS | Transport & logistics | 2019 |
| Svelviken AS | Real estate | 2002 |
| Svelvikstranda Vann Og Avløp AS | Water & waste | 2005 |
| Sørensen Ved Og Mek AS | Agriculture & fishing | 2022 |
| T.T Eiendom AS | Real estate | 2013 |
| Tablez AS | Information & communication | 2026 |
| Tanjoca Invest AS | Real estate | 1997 |
| Tato Holding AS | Professional & scientific | 2018 |
| Telko AS | Information & communication | 1976 |
| Telko Holding AS | Information & communication | 2005 |
| Terminal Invest AS | Professional & scientific | 2012 |
| Thorøyaveien 3 AS | Real estate | 1996 |
| Tilda Fabrics AS | Manufacturing | 2017 |
| Timer Solutions AS | Administrative & support | 1995 |
| Tjuma Grøntvedlikehold AS | Manufacturing | 2021 |
| Tjøme & Hvasser Elektriske AS | Construction | 1990 |
| Tjøme Bil & Motor AS | Wholesale & retail | 2007 |
| Tjøme Blomster AS | Wholesale & retail | 2017 |
| Tjøme Eiendom AS | Real estate | 2004 |
| Tjøme Eiendomsutvikling AS | Real estate | 2024 |