| Tor Holding AS | | 2021 |
| Tor Reidar Stangeland AS | Real estate | 2018 |
| Tore Breiland AS | | 2018 |
| Tore Gjesteland AS | Real estate | 1999 |
| Tore Rygh Holding AS | Real estate | 2013 |
| Torek AS | Professional & scientific | 2018 |
| Torek Drift AS | Professional & scientific | 2022 |
| Torek Eiendom AS | Real estate | 2021 |
| Torjus Bakkene Holding AS | | 2021 |
| Torland AS | Manufacturing | 2020 |
| Torly AS | Financial services | 2016 |
| Torneroseveien 10 AS | Wholesale & retail | 2000 |
| Torneroseveien 12 AS | Real estate | 2006 |
| Torneroseveien 14 AS | Real estate | 2006 |
| Torvmyrvegen 8 AS | | 2020 |
| Total Bolig AS | Real estate | 2017 |
| Total Safety AS | Education | 2018 |
| Total Safety Holding AS | Education | 2009 |
| Total Subsea AS | Real estate | 2017 |
| Totaltech AS | Real estate | 2006 |
| Toto Holding AS | Real estate | 1996 |
| Totoku AS | | 2023 |
| Touch Massage and Spa Services AS | Other services | 2020 |
| Tower AS | Administrative & support | 2012 |
| Towil AS | | 2012 |
| Toy-World AS | Wholesale & retail | 2024 |
| Toyota Rogaland AS | Other services | 2007 |
| Toyota Sørvest AS | Wholesale & retail | 1986 |
| Toyota Sørvest Bilutleie AS | Administrative & support | 2000 |
| TP Advokatfirma Da | Professional & scientific | 2013 |
| TPG Home AS | Real estate | 2016 |
| TPG Home E17 AS | Real estate | 2016 |
| TPG Home R1 AS | Real estate | 2016 |
| TPG Management AS | Real estate | 2017 |
| Trade Force AS | Administrative & support | 2023 |
| Trallfa Capital AS | Administrative & support | 2015 |
| Trallfa Focus AS | Administrative & support | 1986 |
| Trallfa Potteridokken AS | Real estate | 2012 |
| Trallfa Underhaug AS | Real estate | 2017 |
| Tram Invest AS | | 2022 |
| Transaction Executed Da | Wholesale & retail | 2008 |
| Transalp Invest AS | Financial services | 2008 |
| Transport & Flytting AS | Transport & logistics | 2020 |
| Transport AS | Transport & logistics | 2025 |
| Transportteknisk Utvikling Og Assistanse AS | Professional & scientific | 2020 |
| Travelz AI AS | Administrative & support | 2025 |
| Travelz AI Holding AS | | 2025 |
| Travtrener Pål Buer AS | Education | 2019 |
| Tre Hjerter Invest AS | | 2022 |
| Tre Invest AS | Real estate | 1992 |
| Tre Invest II AS | Real estate | 1995 |
| Tre Og Natur AS | Administrative & support | 2025 |
| Tredve 2 AS | Education | 2023 |
| Tree Holding AS | | 2017 |
| Trelico AS | Real estate | 2025 |
| Tren Sandnes AS | Arts & recreation | 2019 |
| Trend Bil AS | Wholesale & retail | 2023 |
| Trend Eiendom AS | Real estate | 2000 |
| Treskalle AS | Manufacturing | 2018 |
| Treskeveien 2 AS | Real estate | 2020 |
| Trestang 2 AS | Real estate | 2017 |
| Trestang 3 AS | Real estate | 2021 |
| Trestang AS | Real estate | 2014 |
| Trettø Olsen Invest AS | Financial services | 2018 |
| Treuhand AS | Professional & scientific | 2015 |
| Tribal AS | Arts & recreation | 2016 |
| Tribility Holding AS | | 2013 |
| Tribility Invest AS | Financial services | 2018 |
| Tribute AS | Hospitality | 2002 |
| Trico Bygg AS | Construction | 2011 |
| Trikløver AS | Real estate | 2023 |
| Trim Towers AS | Real estate | 2006 |
| Trimteateret AS | Other services | 2008 |
| Trine Thornquist AS | Health & social care | 1999 |
| Triple a Services AS | Professional & scientific | 2023 |
| Trippel Bygg AS | Construction | 1987 |
| Trippel V AS | Agriculture & fishing | 2023 |
| Trippel-M AS | Real estate | 2016 |
| Tristar Invest AS | Financial services | 2004 |
| Triton Inspections AS | Professional & scientific | 2024 |
| Trodahl Arkitekter AS | Professional & scientific | 2020 |
| Trodahl Holding AS | Real estate | 2020 |
| Trokon AS | Professional & scientific | 2009 |
| Trol Holding AS | | 2023 |
| Troll Ventures AS | Wholesale & retail | 2012 |
| Trollblokk AS | Manufacturing | 2016 |
| Trolljeger AS | Education | 2016 |
| Trolltech AS | Professional & scientific | 2025 |
| Trolsrud AS | Administrative & support | 2025 |
| Troms Offshore Management AS | Transport & logistics | 2011 |
| Troms Offshore Supply AS | Administrative & support | 2010 |
| Trond Arve Kommedal AS | Construction | 2016 |
| Trond Egeland Holding AS | Manufacturing | 2008 |
| Trond Hedland AS | Construction | 1989 |
| Trond Høie Holding AS | | 2021 |
| Trond Motland AS | Wholesale & retail | 2007 |
| Trondheim Holding AS | Manufacturing | 2025 |
| Trondpeten Musikk Ans | Wholesale & retail | 1993 |
| Trones Consulting & Accounting Services AS | Professional & scientific | 2019 |
| Trones Investering AS | Financial services | 2007 |