| Teaco AS | Professional & scientific | 2011 |
| Team Alfa AS | Professional & scientific | 2024 |
| Team Øygarden AS | | 2026 |
| Tech Nest AS | Other services | 2024 |
| Tee One AS | Information & communication | 2024 |
| Tej Investment AS | Wholesale & retail | 2008 |
| Tekle Drosje&Transport AS | Transport & logistics | 2023 |
| Tekstil-Vask AS | Other services | 2012 |
| Tele Soft AS | Wholesale & retail | 1986 |
| Tempt AS | Wholesale & retail | 2012 |
| Ten Holding AS | Wholesale & retail | 2007 |
| Teo AS | Information & communication | 2022 |
| Terapi Og Stetoskopi AS | Health & social care | 2025 |
| Terminals AS | Real estate | 2022 |
| Teve Eiendom AS | | 2013 |
| TH Stava AS | Professional & scientific | 2012 |
| Thai 1 Helse & Velvære AS | Other services | 2022 |
| Thai Delikatesser AS | Hospitality | 2024 |
| The Basic Shop AS | Wholesale & retail | 2015 |
| The Bergems AS | Real estate | 2021 |
| The Irish Viking AS | Hospitality | 2007 |
| The Room Haugesund AS | Education | 2025 |
| The Strand AS | Hospitality | 2023 |
| The Studio by Crush AS | Wholesale & retail | 2020 |
| The Viking Planet Haugesund AS | Arts & recreation | 2019 |
| Thermotech AS | Manufacturing | 1994 |
| Thomson Holding AS | Hospitality | 2015 |
| Thorax AS | Transport & logistics | 2025 |
| Thormodsen & Opheim Bygg Da | Construction | 2017 |
| Three Barrel Invest AS | Real estate | 2006 |
| THS Brekke AS | Wholesale & retail | 1983 |
| Thuen Bygg & Anlegg AS | Construction | 2025 |
| Thuen Bygg Holding AS | Construction | 2025 |
| Thulice AS | | 2023 |
| Thune Biltransport AS | Transport & logistics | 2006 |
| Thune Holding AS | Wholesale & retail | 2006 |
| THV Haavik Eiendom AS | Real estate | 2024 |
| Thy Engineering AS | Professional & scientific | 2012 |
| Ti Teknologi AS | Professional & scientific | 2023 |
| Tidal Sails AS | Professional & scientific | 2004 |
| Tiempo AS | Professional & scientific | 2014 |
| Tif Holding AS | Real estate | 2008 |
| Tijara AS | Wholesale & retail | 2017 |
| Timing Eiendom AS | Real estate | 2007 |
| Tina Vikse Holding AS | | 2022 |
| Tinamar AS | Transport & logistics | 1994 |
| Tindeland Holding AS | Real estate | 2010 |
| Tindeland Prosjekt AS | Real estate | 2017 |
| Tittelsnesvegen 302E AS | Real estate | 2026 |
| Tjrs AS | Real estate | 2013 |
| TK AS | Real estate | 1985 |
| TK Gruppen AS | Education | 2016 |
| TK Trafikkskole AS | Education | 2016 |
| TKJ Consulting AS | Professional & scientific | 2022 |
| Tkvass Invest AS | | 2025 |
| Tlo AS | | 2014 |
| TM Taksering AS | Real estate | 2018 |
| TML AS | Information & communication | 2024 |
| Tmtk Norge AS | Administrative & support | 2005 |
| TN Investments AS | Real estate | 2026 |
| TNB Amanda AS | Wholesale & retail | 2018 |
| Tobb Invest AS | | 2022 |
| Toft Eiendom AS | Real estate | 1990 |
| Tojj Holding AS | Real estate | 2018 |
| Tollaksen Holding AS | Wholesale & retail | 2005 |
| Tollevik Holding AS | Agriculture & fishing | 2023 |
| Tollevik II AS | Agriculture & fishing | 2023 |
| Tolås Invest AS | Real estate | 2017 |
| Tolås Marketing AS | Administrative & support | 2017 |
| Toma Maling AS | Construction | 2020 |
| Toma Mat AS | Manufacturing | 1997 |
| Tomlar Invest AS | Financial services | 2014 |
| Tonjer Link AS | Education | 2001 |
| Tonjer Media AS | Professional & scientific | 1987 |
| Tonjer Skilt & Dekor AS | Manufacturing | 2001 |
| Tonnes Panorama AS | | 2015 |
| Tony's Gatekjøkken Catering AS | Hospitality | 2014 |
| Tool Garden AS | Information & communication | 2026 |
| Topeka Hagland Greenbulk AS | | 2022 |
| Topp Bakeren AS | Manufacturing | 1985 |
| Topp Bakeren Eiendom AS | Real estate | 2010 |
| Tor Johan Stuve AS | Real estate | 1994 |
| Torana II AS | Financial services | 2015 |
| Torana Invest AS | Financial services | 2017 |
| Torana Investering AS | Financial services | 2017 |
| Tore Haugen Invest AS | Professional & scientific | 2024 |
| Tore Henriksen AS | Wholesale & retail | 2002 |
| Torgersen Holding AS | | 2014 |
| Torggaten 2 AS | Real estate | 2003 |
| Tornborg Shipping AS | Transport & logistics | 1999 |
| Tornes Bulk AS | Transport & logistics | 2019 |
| Tornesbygg AS | Households | 1950 |
| Tosak Holding AS | Construction | 2024 |
| Totalen Eiendom | Real estate | 1952 |
| Totalen Kaffebar AS | Hospitality | 2013 |
| Totalum AS | Real estate | 2016 |
| Toyota Haugesund AS | Other services | 2000 |
| Toyota Haugesund Utleie AS | Administrative & support | 2022 |
| TPH Holding AS | Real estate | 2024 |
| Tra Eiendom AS | | 2006 |