| Sundborg Holding AS | Wholesale & retail | 1991 |
| Sundet Eiendom AS | Real estate | 2001 |
| Sunkarl AS | | 2024 |
| Supervask Norge AS | Other services | 2015 |
| Svein Erik Toldnes Holding AS | Financial services | 2018 |
| Sykkelhuset Eiendom AS | Real estate | 2009 |
| Sykkelhuset Levanger AS | Wholesale & retail | 2007 |
| Søgstad Gård AS | Real estate | 2014 |
| Sønan Eiendom AS | Real estate | 2010 |
| Sørheim Maskin AS | Construction | 1986 |
| Sørlie Auto AS | Wholesale & retail | 2016 |
| Sørmo AS | Other services | 1988 |
| Sørmo Eiendom AS | Real estate | 2022 |
| T Aunan Holding AS | | 2025 |
| T-P Pubdrift AS | Hospitality | 2023 |
| T. Kristiansen AS | Administrative & support | 2025 |
| T.Moa AS | | 2023 |
| T.O. Tangen Bygg AS | Construction | 2016 |
| Tactrl.Ai AS | Administrative & support | 2020 |
| Takst, Arkitekt Og Ingeniør-Tjenester AS | Real estate | 2019 |
| Tannlege Alstad AS | Health & social care | 2008 |
| Tannlege Fostad AS | Health & social care | 2026 |
| Tannlege Kjell Arne Reitan AS | | 2014 |
| Tannlege Nils B Skaar AS | Health & social care | 2023 |
| Tannlege Skatland AS | Health & social care | 2014 |
| Tannlege William Kristiansen AS | Health & social care | 2016 |
| Tannlegene Levanger Sør Da | Health & social care | 2009 |
| Tbk-Eiendom AS | Real estate | 2022 |
| TBV Holding AS | Health & social care | 2013 |
| Tech Nordic AS | Professional & scientific | 2019 |
| TECH1 AS | Professional & scientific | 2013 |
| Teglverket Verdal AS | Real estate | 2014 |
| Telekiosken Levanger AS | Wholesale & retail | 2006 |
| Terik Technology AS | Manufacturing | 2005 |
| Terje Alstad Holding AS | Financial services | 2018 |
| Tetlimo AS | Construction | 2022 |
| Tevo Bil AS | Wholesale & retail | 2015 |
| Thad Eiendom AS | Real estate | 2025 |
| Tierarzt Holding AS | | 2026 |
| Tiga AS | Professional & scientific | 2005 |
| Tina Elden AS | Health & social care | 2012 |
| Tingstad Maskinlag SA | Agriculture & fishing | 1994 |
| Titanium Holding AS | Construction | 2021 |
| Tivoligrillen AS | Wholesale & retail | 2016 |
| Tle AS | Construction | 2013 |
| Tle Eiendom AS | Real estate | 2021 |
| TMM Produksjon AS | Information & communication | 2020 |
| TMS - Eiendom AS | Real estate | 2014 |
| TN Maskin AS | Construction | 2021 |
| Tobit AS | | 2021 |
| Tom Verpe AS | Health & social care | 2020 |
| Tommy Aune Rehn AS | Real estate | 2014 |
| Tore Forbord AS | Financial services | 2008 |
| Toringv Holding AS | Hospitality | 2018 |
| Torsbustaden Skisenter AS | Arts & recreation | 2020 |
| Torsbustaden Veilag SA | Real estate | 1996 |
| Tranaskogen AS | Real estate | 2012 |
| Trattoria Levanger AS | Hospitality | 2026 |
| Tre S Eiendom AS | Real estate | 2025 |
| Trekanten 6 Levanger AS | Real estate | 2014 |
| Trekanten 8 AS | Real estate | 2014 |
| Trekanten Holding AS | Real estate | 2005 |
| Tri Holding AS | | 2019 |
| Troll Entreprenør AS | Administrative & support | 2012 |
| Trollheim Eiendom AS | Manufacturing | 2006 |
| Trygg Leie AS | Real estate | 2021 |
| Trysa AS | | 2021 |
| Trætli Holding AS | | 2024 |
| Trøndelag Betong AS | Construction | 2016 |
| Trøndelag Bolig AS | Real estate | 2015 |
| Trøndelag Byggtjenester AS | Construction | 2017 |
| Trøndelag Fiske Og Fritid AS | Wholesale & retail | 2019 |
| Trøndelag Klima Service Utleie AS | Construction | 2026 |
| Trøndelag Revisjon AS | Professional & scientific | 2010 |
| Trønder-Tv AS | Information & communication | 2013 |
| Trøndergrønt AS | Administrative & support | 2000 |
| Tuan Dinh Khac AS | Hospitality | 2020 |
| Turo Finans AS | Real estate | 2021 |
| Ty-Bø Maskinlag SA | Agriculture & fishing | 2001 |
| Tynes Samdrift Da | Agriculture & fishing | 2005 |
| Tyttebærveien Holding AS | Construction | 2008 |
| Tåf Holding AS | Financial services | 2018 |
| Urds Holding AS | Real estate | 2017 |
| Uri Invest AS | Real estate | 2016 |
| Utleieselskapet AS | Administrative & support | 2007 |
| Uv Holding AS | Administrative & support | 2021 |
| Vague Intelligence AS | Information & communication | 2025 |
| Vaskeriet Arena Event & Konferanse AS | Administrative & support | 2025 |
| Vaxtr AS | | 2024 |
| Vela AS | Wholesale & retail | 1987 |
| Veso Invest AS | | 2021 |
| Veterinær Øyvind Skei AS | Professional & scientific | 2014 |
| Vevle Trade AS | Wholesale & retail | 2023 |
| Viam Holding AS | Professional & scientific | 2019 |
| Victoria Sjøsiden AS | Hospitality | 2020 |
| Vikhammer Nedre AS | Real estate | 2011 |
| Vikhammerstrand AS | Real estate | 2019 |
| Vikhammerstrand Holding AS | Real estate | 2019 |
| Vilde Invest AS | | 2024 |
| Vira Media AS | Professional & scientific | 2016 |