| Jobr Engineering AS | Røyneberg | 2006 |
| Jobraaten & Partners AS | Oslo | 2003 |
| Jobrest AS | Bardufoss | 2019 |
| Jobs Invest AS | Kristiansand S | 2018 |
| Jobswoop AS | Oslo | 2024 |
| Joco AS | Oslo | 2020 |
| Joco Consulting AS | Kristiansand S | 2024 |
| Joco Holding AS | Oslo | 2008 |
| Jocom AS | Oslo | 2013 |
| Jodapro AS | Asker | 2019 |
| Jodasol AS | Kristiansand S | 2022 |
| Jodfabrikken AS | Nesøya | 2015 |
| Jodi AS | Tønsberg | 2017 |
| Jodin Group AS | Oslo | 2026 |
| Joe AS | Jar | 2004 |
| Joe Byrne Electrics Ltd Nuf | Durham Dh7 9Qr | 2025 |
| Joeclub AS | Flatåsen | 2022 |
| Joeni AS | Mosjøen | 2018 |
| Joes Holding AS | Gardermoen | 2022 |
| Jofark AS | Klepp Stasjon | 2024 |
| Jofe AS | Oslo | 2022 |
| Jofi AS | Bergen | 2018 |
| Jofi Ingeniørfirma AS | Gressvik | 1986 |
| Joggende Optikere Da | Stabekk | 2000 |
| Jogn AS | Moss | 2016 |
| Jogo Media AS | Oslo | 2009 |
| Jogra Engineering AS | Stamnes | 2007 |
| Joh Johannson | Oslo | 1891 |
| Joh Vannteknikk AS | Trondheim | 2016 |
| Johab AS | Hafrsfjord | 2021 |
| Johan Arnt AS | Nannestad | 2023 |
| Johan Brobakke AS | Trondheim | 1991 |
| Johan F Aasen AS | Ålesund | 1997 |
| Johan Fossli AS | Frosta | 2012 |
| Johan Lindberg Holding AS | Oslo | 2020 |
| Johan Viktor Olofsson AS | Oslo | 2025 |
| Johann AS | Oslo | 2025 |
| Johanne Borthne AS | Oslo | 2018 |
| JOHANNESS1 AS | Moldjord | 2025 |
| Johannessen & Ljone Finans AS | Bergen | 1994 |
| Johannessen Creative AS | Lillehammer | 2023 |
| Johannessen Prosjekttjenester AS | Sem | 2020 |
| Johansen Kapital AS | Oslo | 2024 |
| Johansen Prosjektstyring AS | Stathelle | 2025 |
| Johansen Revisjon AS | Flekkefjord | 2001 |
| Johanssen AS | Sandnes | 2014 |
| Johansson AS | Hamar | 2021 |
| Johansson Consult AS | Trondheim | 2004 |
| Johansson Consulting Nuf | Oslo | 2021 |
| Johansson Konsulent & Rådgivning AS | Bergen | 1992 |
| Johansson Regnskap AS | Ålesund | 2018 |
| Johja AS | Nesbyen | 2017 |
| Johleo AS | Stavanger | 2016 |
| John Christian Bugge AS | Oslo | 1998 |
| John D Breivoll AS | Tromsø | 1987 |
| John Erik Nilsen AS | Drammen | 2006 |
| John Finan Ltd | Aberdeen Ab16 7Dd Scotland | 2019 |
| John Kristoffersen Arkitektkontor AS | Tromsø | 1989 |
| John Lingen Invest AS | Skåla | 2018 |
| John Martin Oilfield Services Limited | Ab154Zn Aberdeen | 2014 |
| John Olas Andre Holding AS | Haugesund | 2022 |
| John Roger Sørbøe Holding AS | Mandal | 2019 |
| John Spencer Wellsite Geological Consultancy Limited | Gb - Sunderland Sr6 7Dy | 2011 |
| John Underwood Consulting Ltd | Tn25 7Ah Kent | 2011 |
| John Zink Hamworthy Combustion S.R.L. | It-Cap 20871 Vimercate Milan | 2016 |
| John Zink International Luxembourg | 3451 Dudelange | 2009 |
| John-John Myhrvold Holding AS | Skedsmokorset | 2024 |
| Johnek Regnskap AS | Oslo | 2013 |
| Johnny Hansen AS | Lyngseidet | 1993 |
| Johns Bygg & Fasad AB | Halden | 2007 |
| Johns Wind Windows AS | Asker | 2026 |
| Johnsen Chemicals AS | Trollåsen | 2010 |
| Johnsen Foto Og Media AS | Stamsund | 2026 |
| Johnsen Konsulenttjenester AS | Grimstad | 2016 |
| Johnsen, Johnsen, Johnsen & Johansen AS | Gjøvik | 2022 |
| Johnsens Veterinærtjenester AS | Yven | 2015 |
| Johnson Controls Denmark Aps | Dk-8626 Viby J | 2008 |
| Johnson Controls Norway AS | Oslo | 1986 |
| Johnson Downes Consulting Limited | Surrey Kt16 9Be | 2016 |
| Johnson Screens SAS Nuf | Fr-86530 Availles-En-Chatellerault | 2026 |
| Johnsrud Consulting AS | Flatanger | 2022 |
| Johnsrud Media AS | Drøbak | 2020 |
| Joho AS | Kleppe | 2014 |
| Joho Holding AS | Drøbak | 2022 |
| Johre Revisjon AS | Dalen | 2025 |
| Johs. Hansen Management AS | Sandvika | 2020 |
| Johtek AS | Maura | 2013 |
| Johtti Productions AS | Kautokeino | 2020 |
| Join Animation Studio AS | Fjellhamar | 2020 |
| Join Consulting AS | Oslo | 2020 |
| Join Nordics AS | Kristiansand S | 2026 |
| Join Rådgivning AS | Lillestrøm | 2024 |
| Joint Bolig Og Eiendom AS | Oslo | 1997 |
| Joint Survey Group AS | Lillehammer | 2025 |
| Joinvest AS | Sandvika | 2005 |
| Joinyou Ans | Oslo | 2008 |
| Joinyou AS | Oslo | 2013 |
| Jojeko AS | Hosle | 2018 |
| Jojo AS | Tolvsrød | 1998 |
| Jojo Consult AS | Tønsberg | 1999 |