| Jensen Rørservice AS | Jevnaker | 2019 |
| Jensen Snekker Og Tømrerservice AS | Trondheim | 2016 |
| Jensen VVS AS | Fjellhamar | 2008 |
| Jensens Rørleggerservice AS | Ski | 2014 |
| Jenshus Maskin AS | Næroset | 2023 |
| Jenssen & Vaarum Holding AS | Rygge | 2021 |
| Jenssen AS | Kvaløya | 2013 |
| Jenssen Entreprenør AS | Tennevoll | 2007 |
| Jenssen Ventures AS | Tromsø | 2023 |
| Jenssen-System AS | Rygge | 2021 |
| Jenstad Maskin AS | Gjøra | 2013 |
| Jensvold Snekkerservice AS | Bodø | 2015 |
| Jentoft Entreprenør AS | Oteren | 2016 |
| Jentoft Holding AS | Bergen | 2005 |
| Jep Bygg Og Eiendomsutvikling AS | Sandefjord | 2015 |
| Jepsen's Betong AS | Vennesla | 2026 |
| Jermund Mulen AS | Førde | 2026 |
| Jernbane & Anleggsteknikk | Svelvik | 2026 |
| Jernbaneteknikk AS | Gvarv | 2019 |
| Jernbetong AS | Melhus | 1999 |
| Jernbro Industrial Services A/S Nuf | Mongstad | 1995 |
| Jernbro Industrial Services AS | Mongstad | 2011 |
| Jerpstad Maskin AS | Rennebu | 2013 |
| Jerstad VVS AS | Kristiansand S | 2022 |
| Jerzy Andrzej Jarmolowski Jarmo | 80-254 Gdansk | 2006 |
| Jerzy Hoft | 98-160 Pruszkow | 2007 |
| Jerzy Jankowski | 26-400 Przysucha | 2005 |
| Jerzy Jarszewski | 81-125 Gdansk | 2007 |
| Jerzy Kacki Slaskie | 43-600 Jaworzno | 2007 |
| Jerzy Was | Nøtterøy | 2005 |
| JES1 Bygg AS | Fredrikstad | 2019 |
| Jess-Bygg AS | Tynset | 2013 |
| Jess-Bygg Holding AS | Tynset | 2009 |
| Jessen Entreprenør AS | Drag | 2005 |
| Jessen Maskin | Skogn | 2013 |
| Jessheim Bygg Og Maler AS | Jessheim | 2025 |
| Jessheim Elektriske AS | Gardermoen | 2011 |
| Jessheim Rørleggerbedrift AS | Kløfta | 2021 |
| Jessheim VVS & Varmeservice AS | Jessheim | 2019 |
| Jesting Eiendomsservice AS | Oslo | 2006 |
| Jet-Maskin AS | Vang På Hedmarken | 2016 |
| Jetmundsen Elektro AS | Søreidgrend | 2005 |
| Jetta-Talo Nuf | Fi-69950 Perho | 2023 |
| Jeu Holding AS | Hylkje | 2010 |
| Jev Holding AS | Eikelandsosen | 2022 |
| Jeva Håndverk AS | Otta | 2000 |
| Jevgenijs G AS | Os | 2019 |
| Jevnaker Elektriske Forretning AS | Jevnaker | 1987 |
| Jevnaker Malerservice AS | Jevnaker | 2022 |
| Jevnaker Maskin AS | Aurland | 2026 |
| Jevne Bygg AS | Vang I Valdres | 2016 |
| JF Bygg AS | Ytre Enebakk | 2018 |
| JF Maskin AS | Lier | 2015 |
| JF Snekkerservice AS | Færvik | 2014 |
| JFL AS | Vestby | 2019 |
| JFR Sia | Lv-1082 Riga | 2020 |
| Jfsunde Invest AS | Snartemo | 2024 |
| JG Bygg AS | Tromsdalen | 2019 |
| JG Bygg Og Rehabilitering AS | Lier | 2025 |
| JG Maling AS | Alta | 2024 |
| JG Maskin AS | Dimmelsvik | 2019 |
| JG Plastsveis AS | Holmestrand | 2024 |
| JG Snekkeren AS | Stokke | 2013 |
| JGB Holding AS | Larvik | 2024 |
| JGB Invest AS | Vatnestrøm | 2015 |
| JGP Bygg AS | Larvik | 2026 |
| JH Bruun AS | Hokksund | 2007 |
| JH Bygg AS | Kongsvinger | 2012 |
| JH Byggmontage AB Nuf | Se-439 31 Onsala | 2024 |
| JH Graving Og Transport AS | Lysøysundet | 2019 |
| JH Installasjon AS | Hordvik | 2016 |
| JH Prosjekt AS | Bjoneroa | 2019 |
| JH Service AS | Lonevåg | 2022 |
| JH Spårservice AB | Se-734 32 Halstahammar | 2001 |
| JH Spårservice AS | Lillestrøm | 2014 |
| JH Svenske Sten AB | 38062 Mörbylånga | 2014 |
| Jh-Bygg AS | Namsos | 2022 |
| JHL Bygg AS | Ørje | 2023 |
| Jho Maskin Og Transport AS | Os | 2018 |
| JHP Bygg AS | Stavanger | 2016 |
| Jht-Maskin AS | Alta | 2007 |
| JHV Multiservice AS | Finnsnes | 2021 |
| Ji Bygg AS | Vestby | 1994 |
| Ji&B Holding AS | Horten | 2023 |
| Jia Holding AS | Frosta | 2013 |
| Jigemark & Bygg AB | Oslo | 2006 |
| Jih Graveservice AS | Skien | 2005 |
| Jim Håre Byggtjenester AS | Prestfoss | 1987 |
| Jim Ingvaldsen Bygg Og Betong AS | Tverlandet | 2020 |
| Jim's Betong AB | Se-458 32 Färgelanda | 2023 |
| Jimess Malerservice AB | Se-67151 Arvika | 2006 |
| Jin Maskin AS | Svelgen | 2006 |
| Jir Holding AS | Sola | 2018 |
| Jiri Suchomel | Cz- 1391 72 Tabor | 2013 |
| Jiri Toth Nuf | Cz-26203 Chotilsko | 2025 |
| Jirvelius World Wide Microtrenching AB Nuf | Se-716 31 Fjugesta | 2025 |
| Jisu Maskin AS | Roa | 2024 |
| JJ Anlegg AS | Elverum | 2026 |
| JJ Bygg Da | Frogner | 2012 |
| JJ Byggespecialister AS | Rennesøy | 2018 |