| Unitrust AS | Fjellhamar | 2021 |
| Univent Kristiansand AS | Kristiansand S | 2007 |
| Universal AS | Moss | 1988 |
| Universal Malerservice AS | Ålesund | 2024 |
| Universal Rørconsult & Takst AS | Oslo | 2025 |
| Universell Bolig AS | Bjørnemyr | 2008 |
| Unnestad Bygg AS | Skiptvet | 2018 |
| Uno AS | Hvalstad | 1983 |
| Uno Bygg AS | Kristiansand S | 1998 |
| Uno Consept AS | Bodø | 2018 |
| Unoeiendom AS | Tverlandet | 1996 |
| Unos AS | Nedenes | 2017 |
| Unu AS | Måløy | 1987 |
| Uos AS | Frogner | 2020 |
| Up Bygg AS | Tromsdalen | 2014 |
| Up Entreprenør A/S | Lillestrøm | 2024 |
| Upm Service Norge AS | Høvik | 2022 |
| Uponor Infra OY | Fi-01511 Vaataa | 2015 |
| Uppal Maskin AS | Sundebru | 2015 |
| Uppe | Lv-3042 Brankas Ozolnieku Nov | 2010 |
| Upplands Dyk & Anlagging | Se-211 37 Malmö | 2014 |
| Uppstad Anleggservice AS | Rysstad | 2015 |
| Uppstad Holding AS | Rysstad | 2021 |
| Uppstad Kraftverk AS | Rysstad | 2012 |
| Uppstad VVS AS | Rysstad | 2022 |
| Uppstad VVS Avdeling Hovden AS | Hovden I Setesdal | 2021 |
| Ur Maskin AS | Jørpeland | 1986 |
| Urang Maskin & Transport AS | Urangsvåg | 2021 |
| Urban Cellar Prosjekt & Invest AS | Oslo | 2014 |
| Urban Elektro AS | Stranda | 2015 |
| Urban Olsson Bygg & Industriservice AB | Halden | 2011 |
| Urban Reuse AS | Slemmestad | 2018 |
| Urban Reuse Norway AS | Slemmestad | 2005 |
| Urbana Fasade AS | Oslo | 2016 |
| Urbana Våtrom AS | Oslo | 2023 |
| Urbanhus Bergen AS | Paradis | 2016 |
| Urbanmur AS | Hunndalen | 2026 |
| Urbe Services AS | Oslo | 2023 |
| Urd Klima Oppdal AS | Oppdal | 1999 |
| Urd Klima Sandnes AS | Sandnes | 1999 |
| Urdahl Maskin AS | Flisa | 2021 |
| Urevatn Holding AS | Tingvatn | 2016 |
| Urheims Elektrokompani AS | Bergen | 1975 |
| Urke & Madsen AS | Skodje | 2001 |
| Urke Kjøleteknikk AS | Sykkylven | 2020 |
| Urke Maskinservice AS | Ulsteinvik | 2025 |
| Urlaub in Norwegen AS | Bremnes | 2020 |
| Urskog Byggservice AS | Valnesfjord | 2016 |
| Urskog Eiendom AS | Valnesfjord | 2016 |
| Ursus Service AS | Søgne | 2022 |
| Us Operation AS | Oslo | 2024 |
| Us Service AS | Raudsand | 2024 |
| Uskugi Ogolno - Budowlane Sadowski Slavomir | Sykkylven | 2004 |
| Uslugi Budowlane Artur Debek | Pl-031 33 Warszawa | 2006 |
| Uslugi Budowlane Przemyslaw Kurek | Pl-62-400 Slupca | 2018 |
| Uslugi Budowlane Tom-Bud Jechanowski Tomasz-Stanislaw | Pl-07-420 Kadzidlo | 2011 |
| Uslugi Budowlane Tomasz Müller | 83-330 Zukowo | 2010 |
| Uslugi Buoowlane Buildning Repair & Construction | Oslo | 2004 |
| Uslugi Ciesielskie Dariusz Gasiemca | 34-521 Zab | 2008 |
| Uslugi Glazurnicze Dariusz Jakubowicz Mistrz Glazurnik Nuf | Pl-70831 Szczecin | 2016 |
| Uslugi Malarskie Dawid Przychodzki Nuf | 08-400 Garwolin | 2010 |
| Uslugi Malarsko-Remontowe Piotr Antkowiak | 80-392 Gdansk | 2005 |
| Uslugi Ogolnobudawlane Rafal Myszk | Lepsøy | 2015 |
| Uslugi Ogolnobudowlane Artur Henryk Mlodzianowski | Pl-80364 Gdansk | 2005 |
| Uslugi Ogolnobudowlane Grzegorz Skupinski | 55-300 Sroda Slaska | 2006 |
| Uslugi Ogolnobudowlane I Instalacyjme Marian Dworzycki | Degernes | 2012 |
| Uslugi Ogolnobudowlane Jamroz Wojciech | 34-730 Mszana Dolna | 2006 |
| Uslugi Ogolnobudowlane Przemyslaw Grzywacz | Pl- 72 110 Przybiernow | 2017 |
| Uslugi Ogolnobudowlane Tarczynski | 39-432 Gorzyce | 2006 |
| Uslugi Remontowe Montaz Stolarki Budowlanej Krzysztof Hopa Nuf | 78-550 Czaplinek | 2025 |
| Uslugi Remontowo Budowlane Alpa Krzyszof Wardyn | 83-400 Koscierskie | 2016 |
| Uslugi Remontowo-Budowlana Banaszak Slawomir | Horten | 2007 |
| Uslugi Remontowo-Budowlane Adam Stopka | Pl-34-470 Czarny Dunajec | 2010 |
| Uslugi Remontowo-Budowlane Dariusz Kowalczyk | Pl-66-304 Brojce | 2012 |
| Uslugi Remontowo-Budowlane Jacek Marek Majkowski | 07-400 Ostroleka | 2005 |
| Uslugi Remontowo-Budowlane Marek Grosch Nuf | Elverum | 2009 |
| Uslugi Remontowo-Budowlane Naciej Pawel Matuszewski | Vinterbro | 2013 |
| Uslugi Remontowo-Budowlane Wrona | Pl-27-400 Ostroeiec Swietokrzyski | 2016 |
| Uslugi Remontowo-Budowlany Jac Jack Wziatek | Oslo | 2006 |
| Uslugi Stolarsko Budowlane Trzyszof Zuber | 81-589 Gdynia | 2006 |
| Usm AS | Vihals | 2019 |
| Ustad Drift AS | Snillfjord | 2023 |
| Ustaoset Panorama AS | Morvik | 2018 |
| Usterud Anlegg AS | Risdal | 2012 |
| Utbjoa Bygg AS | Stavanger | 2022 |
| Utbjoa Rehab AS | Stavanger | 2023 |
| Utbygging Møre Prosjekt AS | Kristiansund N | 2009 |
| Utcon Byggservice AS | Horten | 2026 |
| Uteglass AS | Haslum | 2012 |
| Uteglass Montasje AS | Haslum | 2017 |
| Utehjelpen AS | Rykkinn | 2024 |
| Uteluksus AS | Billingstad | 2020 |
| Utemiljø Entreprenør AS | Tønsberg | 2023 |
| Uteområdet AS | Oslo | 2024 |
| Uterom Entreprenør AS | Skedsmokorset | 2020 |
| Uteromsgruppen AS | Straume | 2016 |
| Utetjenester AS | Sørum | 2024 |
| Utgaard AS | Trondheim | 1987 |
| Utgaard Invest AS | Trondheim | 2005 |
| Utgard Entreprenør AS | Fagernes | 2016 |