| Jon Røkenes Holding AS | Alta | 2005 |
| Jon Solberg AS Beslagfabrikk | Lonevåg | 1972 |
| Jon Vidar Rasmussen Holding AS | Hyggen | 2005 |
| Jonas & Bengt Marinservice AB | Se-47396 Henån | 2019 |
| Jonas Sivertsen Holding AS | Levanger | 2018 |
| Jondal Precision Industries A.S | Jondal | 1975 |
| Jonelis AB Nuf | Se-692 34 Kumla | 2019 |
| Jonn Skaar Service AS | Hønefoss | 2015 |
| Jonny Horgen Holding AS | Lierstranda | 2022 |
| Jons Kontor AS | Ålesund | 1987 |
| Jonson Controls Reycycling GmbH | 30419 Hannover | 2008 |
| Jonssen Holding AS | Fjellhamar | 2024 |
| Jonsten AS | Råde | 2015 |
| Jopi AS | Lørenskog | 2018 |
| Jor Farms AS | Oslo | 2018 |
| Jordanes Holding AS | Oslo | 2018 |
| Jordanes Invest AS | Oslo | 2018 |
| Jordanes Investments AS | Oslo | 2013 |
| Jordanes Investments Holding AS | Oslo | 2013 |
| Jordens Arv AS | Tønsberg | 2022 |
| Jordfabrikken AS | Levanger | 2002 |
| Jordhelse AS | Åsgårdstrand | 2020 |
| Jordi Bernad Bougault Nuf | Es-08130 Barcelona | 2025 |
| Jordnær AS | Frosta | 2011 |
| Jorids Lefsebakeri AS | Stokmarknes | 2012 |
| Jorkjend Båt AS | Ottestad | 2009 |
| Joro Invest AS | Støren | 2018 |
| Joskjør AS | Roan | 2022 |
| Joss AS | Lillestrøm | 2006 |
| Jostedal Industrier AS | Jostedal | 2013 |
| Jotek AS | Moss | 1995 |
| Jotne Ankers AS | Tistedal | 1998 |
| Jotne Holding AS | Fornebu | 2017 |
| Joto Møbelstopp Ans | Kviby | 1990 |
| Jotron AS | Larvik | 1967 |
| Jotron Skipper AS | Oslo | 1992 |
| Jotun A/S | Sandefjord | 1971 |
| Jotun Powder Coatings AS | Sandefjord | 1997 |
| Jotunheim Fisk AS | Espedalen | 2025 |
| JP Mekk AS | Finnås | 2024 |
| JP Shipping AS | Sandefjord | 2012 |
| JPL Services AB Nuf | Se-45337 Lysekil | 2021 |
| JPS Welding OY | Fi-60150 Seinäjoki | 2012 |
| JPT AS | Sandnes | 2009 |
| JR Service AS | Tønsberg | 2017 |
| JR Welding & Installation | 93100 Pudasjårvi | 2008 |
| JRL AS | Oppegård | 1999 |
| Jrtech Spolka Z Ograniczona Odpowiedzialnoscia Nuf | 05-825 Grodzisk Mazowiecki | 2024 |
| JS Mekaniske Verksted AS | Fjellstrand | 2008 |
| JS Stål Aps Nuf | Dk-9400 Nørresundby | 2019 |
| Jse Helle Holding AS | Dale I Sunnfjord | 2019 |
| JT Arnesen Holding AS | Birkeland | 2020 |
| JTM Produkt AB | Se-981 91 Jukkasjärvi | 2015 |
| Jual Welding SP. Z O.O. | 00-382 Warszawa | 2014 |
| Jubel Games AS | Oslo | 2023 |
| Jubi Thaisilke Sysenter Ans | Oslo | 2007 |
| Jubida AS | Oslo | 1998 |
| Jubs Bygg Og Industri AS | Frosta | 2017 |
| Judys Atelier AS | Kristiansand S | 2016 |
| Juga Mikrobryggeri AS | Lakselv | 2017 |
| Juhls Silver Gallery AS | Kautokeino | 1990 |
| Julanta AS | Grong | 2023 |
| Juliannes Rammeverksted AS | Mo I Rana | 2017 |
| Julie Sandlau | Dk-2900 Hellerup | 2026 |
| Julius & Ørenberg Bokbinderi AS | Oslo | 2025 |
| Juliussen Maskin AS | Lierskogen | 2023 |
| Juliusz Szymanski Nuf | 07-202 Mazowieckie | 2025 |
| JUNGE Norsk avdeling av utenlandsk foretak NUF | Oslo | 1997 |
| Jungel Juice AS | Hafslo | 2003 |
| Juno Larvik AS | Larvik | 1991 |
| Just Be AS | Kristiansand S | 2022 |
| Jutul AS | Leira I Valdres | 1992 |
| Juveler Conrad Langaard AS | Oslo | 1983 |
| Juvikprodukt AS | Aukra | 2017 |
| Juwa AS | Lierstranda | 2014 |
| Jve Service | Nl-4338Pd Ritthem | 2025 |
| JW Machinery Spolka Z Ograniczona Odpowiedzialnoscia Nuf | 20-824 Lublin | 2022 |
| JWW Invest Nuf | Pl-40-161 Katowice | 2021 |
| Jydsk Montage & Svejseteknik Aps | Dk-9560 Hadsund | 2008 |
| Jysk Montasje- Og Sveiseteknikk Nuf | Dk-9560 Hadsund | 2022 |
| Jysk Skorstens Service | 6771 Gredstedbro | 2014 |
| Jytte Fossum | Dk-1370 København K | 2007 |
| Jacob Bjørge AS | Ellingsøy | 1979 |
| Johs. H. Giæver A/S | Havnnes | 1986 |
| Julius Johannessen & Sønner A/S | Hafrsfjord | 1947 |
| Jåblom Bakst AS | Haugesund | 2018 |
| Jåblom Invest AS | Haugesund | 2021 |
| Jåttå Gårdsbryggeri AS | Stavanger | 2018 |
| Jæder AS | Ålgård | 1983 |
| Jædergruppen AS | Ålgård | 2024 |
| Jærakevitt AS | Bryne | 2007 |
| Jærbakeren Arne Johannesen AS | Kleppe | 1997 |
| Jærbjelken Norge AS | Bryne | 2020 |
| Jæreggprodukter AS | Sandnes | 2015 |
| Jæren Avtale AS | Vigrestad | 2020 |
| Jæren Energi Holding AS | Stavanger | 2017 |
| Jæren Gravstein AS | Bryne | 2023 |
| Jæren Holding AS | Varhaug | 2005 |
| Jæren Kjøkken AS | Vigrestad | 2021 |
| Jæren L Eiendom AS | Varhaug | 1997 |