| TP Bygg AS | Oslo | 2019 |
| TP Byggentreprenør AS | Trondheim | 2019 |
| TP Elektro AS | Dokka | 2007 |
| TP Entreprenør AS | Gjøvik | 2021 |
| TP Holding AS | Skien | 2019 |
| TP Maskin Finnsnes AS | Finnsnes | 2000 |
| TP Multi Da | Skjolden | 2017 |
| TP Total AS | Veggli | 2014 |
| TP Ventilasjon AS | Søgne | 2018 |
| Tpa Bygg AS | Nøtterøy | 2015 |
| Tpa Holding AS | Paradis | 2005 |
| TPL Byggmesterfirma AS | Kristiansand S | 2001 |
| TPM Bygg AS | Oslo | 2015 |
| TPM Industrimålning AB | Se-802 91 Gävle | 2016 |
| Tpo Rørleggerbedrift AS | Fjellstrand | 2016 |
| TPP Holding AS | Trondheim | 2022 |
| TPR Eiendom Bygg AS | Oslo | 2022 |
| TR Byg & Montage Nuf | Dk-7330 Brande | 2014 |
| TR Bygg AS | Nedenes | 2024 |
| TR Byggtjenester AS | Fredrikstad | 2019 |
| TR Maskin AS | Garnes | 2013 |
| TR Montage I Karlstad AB | Se-66733 Forshaga | 2012 |
| TR Næringsbygg AS | Greåker | 2020 |
| TR Service AS | Mandal | 2020 |
| TR Tak Og Membran AS | Vinterbro | 2016 |
| Tr-Service AS | Flekkerøy | 2013 |
| Tr/T Holding AS | Grålum | 2023 |
| Traagstad Sandblåsing Og Sprøytemaling AS | Eidsberg | 2018 |
| Traaseth Eiendom AS | Øyer | 2018 |
| Trace B.V. | 3500 Gm Utrecht | 2008 |
| Tracktech Sverige AB Nuf | Årnes | 2021 |
| Trad AS | Bardufoss | 2020 |
| Tradd Service AS | Vik I Sogn | 2025 |
| Tradeco Sikkerhet AS | Fetsund | 2009 |
| Tradex Norge | Oslo | 2014 |
| Tradisjonelt Bygg Håndverk AS | Oslo | 1978 |
| Tradisjonsbygg AS Sunndalsøra | Sunndalsøra | 1996 |
| Tradisjonsbygg Entreprenør AS | Fåvang | 1999 |
| Tradisjonshaandtverk AS | Åmot | 2003 |
| Tradisjonshandverkaren AS | Torvastad | 2021 |
| Tradisjonshytter AS | Røn | 2005 |
| Tradisjonshåndverk AS | Staubø | 2020 |
| Tradisjonshåndverk Weidner AS | Hunndalen | 2017 |
| Tradisjonshåndverkeren AS | Hauge I Dalane | 2019 |
| Tradisjonslaft AS | Beitostølen | 2002 |
| Tradisjonsmur AS | Oppdal | 2010 |
| Tradmur Eiendom AS | Oppdal | 2017 |
| Tradmur Entreprenør AS | Ottestad | 2024 |
| Tradmur Holding AS | Ottestad | 2024 |
| Trafik & Fritid Skandinavien AB Nuf | Se-246 43 Löddeköpinge | 2019 |
| Trafikklederen AS | Kopervik | 2019 |
| Trafikkskilting AS | Lalm | 2013 |
| Trafikkteknikk AS | Langhus | 2023 |
| Trafo Tech AS | Nordre Frogn | 2025 |
| Traftec AS | Arendal | 2011 |
| Tragethon AS | Geilo | 2016 |
| Trainservice AS | Vestmarka | 2015 |
| Traktor & Gravemaskindrift AS | Skreia | 2004 |
| Traktor Og Vaktmestertjenester AS | Dombås | 2018 |
| Traktor Terje AS | Tana | 2015 |
| Traktor Transport AS | Larvik | 2002 |
| Traktorentreprenøren AS | Ulset | 2020 |
| Traktorlaget AS | Nordli | 1983 |
| Tramonte Norway | Roma 50 Cap 30010 | 2018 |
| Trampe Holding AS | Hylkje | 2021 |
| Tran VVS AS | Dilling | 2021 |
| Tranberg Service Og Vedlikehold AS | Biristrand | 2025 |
| Tranbok AS | Halden | 2023 |
| Tranby Bygg & Sanering AS | Tranby | 2016 |
| Tranby Tømrerne AS | Tranby | 2018 |
| Trane Håndverk AS | Lakselv | 2025 |
| Trangesmauet 1A AS | Oslo | 2016 |
| Trangvik Maskin AS | Tolga | 2005 |
| Transforming Design AS | Grøtavær | 2021 |
| Transgrav AS | Ytre Enebakk | 1994 |
| Transpectus AB | Se-413 23 Göteborg | 2019 |
| Transpol AS | Førde | 1999 |
| Transpol Bygg AS | Midsund | 2015 |
| Transport & Anlegg Kragerø AS | Helle | 2015 |
| Transport & Maskin AS | Bergen | 2003 |
| Transport Drift Og Vedlikehold AS | Nittedal | 2017 |
| Transport Og Gravearbeider AS | Oslo | 2018 |
| Transport Og Graving Limited Nuf | Haugesund | 2024 |
| Transport Og Gulvstøp AS | Os | 2001 |
| Transport Service Bergen AS | Blomsterdalen | 2009 |
| Transportkjøling Norge AS | Trondheim | 2018 |
| Transtema Norge AS | Oslo | 2007 |
| Transtema Sem AS | Tolvsrød | 1956 |
| Tranøyveien 6 AS | Bodø | 2015 |
| Trap Krzysztof Malak Spolka Jawna | 71-204 Szczecin | 2007 |
| Trapp Bauservices GmbH | Oslo | 2007 |
| Trappe Snekkeriet AS | Reistad | 2023 |
| Trappeheis Nord AS | Sørkjosen | 2017 |
| Trappekaren AS | Bangsund | 2021 |
| Traser Trafo Servisi Elektromekanik Bakim Sanayi Ve Turizm Ticaret Anonim Sirketi Nuf | Tr-34746 Istanbul | 2026 |
| Trasé AS | Østerås | 2015 |
| Tratec AS | Farsund | 1999 |
| Tratec Teknikken AS | Farsund | 2006 |
| Traust Byggeservice AS | Oslo | 2000 |
| Travbuilders | Ee-10916 Talllinn | 2018 |