| Thermo Electron Sweden AB Nuf | Se-112 93 Stockholm | 2006 |
| Thermo Fisher Diagnostics AS | Oslo | 2003 |
| Thermo Fisher Scientific B.V. | 4817Bl Breda | 2008 |
| Thermo Lignum International GmbH | At-5020 Salzburg | 2021 |
| Thermobygg AS | Avaldsnes | 2013 |
| Thermocut AS | Larvik | 2007 |
| Thermopipe Insulation Products AS | Nesbyen | 2014 |
| Thermowiper Norway AS | Ulefoss | 2012 |
| Thero AS | Kristiansund N | 2026 |
| These Go to 11 AB Nuf | Se-116 24 Stockholm | 2026 |
| Thesilkyhub AS | Oslo | 2020 |
| Thevenin Data AS | Trondheim | 1992 |
| Thevikingshop AS | Utvik | 2020 |
| THG Butikksystemer Nuf | Knarrevik | 2008 |
| Thi AS | Flekkerøy | 2017 |
| Thibeko AS | Tolvsrød | 2025 |
| Thiim AS | Rørvik | 2005 |
| Thiink AS | Kristiansand S | 2021 |
| Thingnes Holding AS | Naustdal | 2013 |
| Think Big AS | Sandefjord | 2023 |
| Think Liquid AS | Oslo | 2023 |
| Thinlight Norge AS | Harstad | 2013 |
| Thinthan Asia Food AS | Borgenhaugen | 2019 |
| Third Wave AS | Krokkleiva | 2018 |
| Thirdlinks Oü Nuf | Oslo | 2026 |
| Thisway Holding AS | Hosle | 2021 |
| Thitutt AS | Flekkerøy | 2019 |
| Thma Holding AS | Hordvik | 2020 |
| Thoja AS | Verdal | 2011 |
| Thom Andersen Holding AS | Froland | 2017 |
| Thomann GmbH | De-96138 Burgebrach | 2020 |
| Thomas Andre Eike AS | Stavanger | 2023 |
| Thomas Andreassen Dagligvare AS | Sørreisa | 2018 |
| Thomas Broadbent & Sons Limited | Huddersfield Hd1 3Ea England | 1995 |
| Thomas Erik Ekjord AS | Gjettum | 1987 |
| Thomas Garstad Holding AS | Fauske | 2024 |
| Thomas Haugen AS | Rolvsøy | 2025 |
| Thomas Haukedal AS | Stathelle | 2024 |
| Thomas Hjelmsø AS | Evenskjer | 2018 |
| Thomas Huse Invest AS | Solbergelva | 2005 |
| Thomas Johnsen Dagligvare AS | Harstad | 2025 |
| Thomas Leker Butikk 2 AS | Oslo | 2023 |
| Thomas Leker Butikk AS | Oslo | 2023 |
| Thomas Leker Flå AS | Flå | 2023 |
| Thomas Leker Holding AS | Bekkestua | 2005 |
| Thomas Leker Kozmos Sandvika AS | Sandvika | 2023 |
| Thomas Leker Sandvika AS | Sandvika | 2023 |
| Thomas Leker Ski AS | Ski | 2023 |
| Thomas Leker Storo AS | Oslo | 2023 |
| Thomas Opsahl Maskin Og Metall AS | Holmestrand | 2023 |
| Thomas Sabo GmbH & Co KG Nuf | 91207 Lauf / Pegnitz | 2014 |
| Thomas Theodor AS | Alvdal | 2026 |
| Thomas Vikshåland AS | Avaldsnes | 2022 |
| Thomas Westvold AS | Bærums Verk | 2017 |
| THOMASSEN1960 AS | Vennesla | 2006 |
| Thomat AS | Heggedal | 2014 |
| Thomsen Agenturer AS | Nyborg | 1991 |
| Thomsen Lie Holding AS | Halden | 2005 |
| Thomsengården Hus & Hage AS | Verdal | 2025 |
| Thomèe Gruppen AB Nuf | Se-202 13 Malmö | 2014 |
| Thon Gjenbruk AS | Oslo | 2020 |
| Thonipa AS | Ålesund | 2002 |
| Thor Arntzen & Co Drift AS | Sørvågen | 2022 |
| Thor Arntzen & Co Holding AS | Sørvågen | 2022 |
| Thor Auto AS | Porsgrunn | 2025 |
| Thor Bakkens Eftf AS | Jostedal | 2015 |
| Thor Heldal AS | Nesttun | 1995 |
| Thor R Nilsen AS | Stathelle | 1981 |
| Thor Thermo Clothing AS | Skien | 2020 |
| Thor Vidar Nilsen AS | Ågotnes | 2001 |
| Thor Westad AS | Nesbru | 1962 |
| Thorbjørn Myklebust AS | Sogndal | 2017 |
| Thord Paulsen AS | Odda | 1999 |
| Thore Holding AS | Skien | 2005 |
| Thoresen & Moen Trading AS | Oslo | 1974 |
| Thoresen Anlegg Og Transport AS | Yven | 2004 |
| Thoresens Brille Og Kontaktlinsesenter AS | Råde | 1980 |
| Thoresens Marketing Ans | Stavanger | 2003 |
| Thorgersen Bygg AS | Kabelvåg | 2022 |
| Thorgersen Holding AS | Skotterud | 2005 |
| Thorium Norway AS | Oslo | 2015 |
| Thormax AS | Ålesund | 2009 |
| Thormodsen Holding AS | Stavanger | 2005 |
| Thorn Norge AS | Oslo | 1973 |
| Thornegården Antikvariat AS | Son | 2016 |
| Thoro Investment Group Da | Godvik | 2006 |
| Thors AS | Lena | 2015 |
| Thors Garage AS | Halden | 2012 |
| Thorsdag AS | Trondheim | 2008 |
| Thorsen Bil AS | Sunde I Sunnhordland | 2017 |
| Thorsen Kontormaskiner AS | Kokstad | 2001 |
| Thorsen Kontorsystemer AS | Kokstad | 2001 |
| Thorsen Maskin & Miljø AS | Kokstad | 2001 |
| Thorstad Mat AS | Brumunddal | 2022 |
| Thorstensen AS | Karmsund | 2015 |
| Thorstensen Holding AS | Oslo | 2005 |
| Thorstensen Jern Og Farge AS | Oslo | 2003 |
| Thorstensen Trading AS | Karmsund | 2016 |
| Thorstvedt Industriservice AS | Randaberg | 2012 |
| Thorsønn AS | Oslo | 2014 |