| Joh Johannson Invest AS | Information & communication | 2016 |
| Joh Jørg Backe AS | Wholesale & retail | 1941 |
| Joh-System AS | Wholesale & retail | 1998 |
| Joh. H. Andresens Vei 5 AS | Real estate | 2013 |
| Joh. Jørg. Backe CC Vest AS | Wholesale & retail | 2013 |
| Joh. Jørg. Backe Storo AS | Wholesale & retail | 2023 |
| Joh. Jørg. Backe Strømmen AS | Wholesale & retail | 2012 |
| Johan Arnt Holding AS | Arts & recreation | 2019 |
| Johan Bjørdal AS | Real estate | 2019 |
| Johan Bojers Vei AS | Real estate | 2022 |
| Johan Evjes Vei 11 AS | Real estate | 2018 |
| Johan Follestads Vei 9 AS | Real estate | 2018 |
| Johan Follestadsvei 18 AS | Real estate | 2017 |
| Johan Follestadsvei 19 AS | Real estate | 2018 |
| Johan Lindberg Holding AS | Professional & scientific | 2020 |
| Johan Michelet AS | Administrative & support | 1920 |
| Johan Sandstrøm Byggare | Construction | 2004 |
| Johan Scharffenbergsvei 116 Eiendom AS | Real estate | 2014 |
| Johan Skjolden AS | Education | 2024 |
| Johan Viktor Olofsson AS | Professional & scientific | 2025 |
| Johanan Gruppen AS | Wholesale & retail | 2020 |
| Johann AS | Professional & scientific | 2025 |
| Johann Holding AS | | 2024 |
| Johanne Borthne AS | Professional & scientific | 2018 |
| Johanne Cornelia AS | Other services | 2023 |
| Johanne Skolt AS | Real estate | 2006 |
| Johannes Benestad AS | Real estate | 2001 |
| Johannes Brunsgate 12 D/E AS | Households | 1939 |
| Johannes Invest AS | Information & communication | 2020 |
| Johannes Nossum & Co AS | | 2023 |
| Johannesborg Eiendom AS | Real estate | 2025 |
| Johannesson Ventilasjonsmontasje AS | Construction | 2020 |
| Johansen & Nerell AS | Manufacturing | 2000 |
| Johansen & Skuggen AS | Other services | 2024 |
| Johansen & Sønn Gulvsliperi AS | Construction | 2011 |
| Johansen Bad Og Rørservice AS | Construction | 2006 |
| Johansen Eiendomstakst AS | Real estate | 2022 |
| Johansen Kapital AS | Professional & scientific | 2024 |
| Johansen VVS AS | Construction | 1997 |
| Johansson Consulting Nuf | Professional & scientific | 2021 |
| Johansson Invest | | 2021 |
| Johdi AS | | 2007 |
| Johema AS | Real estate | 2016 |
| Johera AS | Arts & recreation | 2019 |
| John B Ruud AS | Real estate | 1971 |
| John Christian Bugge AS | Professional & scientific | 1998 |
| John Høiness AS | Real estate | 1964 |
| John P Pedersen & Søn AS | Transport & logistics | 1994 |
| John Roger Hansen Invest AS | Real estate | 2005 |
| Johnek Regnskap AS | Professional & scientific | 2013 |
| Johnny Wallin Holding AS | | 2024 |
| Johnny's Pizza & Burger AS | Hospitality | 2026 |
| Johns Holding AS | | 2005 |
| Johnsen Brøgger Holding AS | | 2020 |
| Johnsen Mat AS | Wholesale & retail | 2022 |
| Johnsenøyborg Holding AS | | 2026 |
| Johnson Controls Norway AS | Professional & scientific | 1986 |
| Johnsrud Holding AS | | 2022 |
| Johre Holding AS | Financial services | 2013 |
| Johre Trading AS | | 2021 |
| Johs Bjerke Elektro Da | Construction | 1988 |
| Johs Brunsgt 10 AS | Real estate | 2004 |
| Johs E. Sæther AS | Real estate | 2005 |
| Johs Møller Maskin AS | Wholesale & retail | 1998 |
| Johs Solberg AS Ingeniør Og Entreprenørforretning | Real estate | 1985 |
| Johs. Ringen Eftf. AS | Arts & recreation | 2017 |
| Johu Holding AS | Financial services | 2016 |
| Join Consulting AS | Professional & scientific | 2020 |
| Join Invest AS | Construction | 2009 |
| Joined Ultimate Music Production Ans | Information & communication | 1991 |
| Joinevent AS | Information & communication | 2019 |
| Joint Action AS | Information & communication | 2019 |
| Joint Bolig Og Eiendom AS | Professional & scientific | 1997 |
| Joinyou Ans | Professional & scientific | 2008 |
| Joinyou AS | Professional & scientific | 2013 |
| Jojada AS | Financial services | 2020 |
| Joji House AS | Information & communication | 2026 |
| Jojo Agenturer AS | Wholesale & retail | 2013 |
| Jojo Group AS | | 2024 |
| Jojo's Mojo Da | Administrative & support | 2006 |
| Jojoha Handel Og Invest AS | | 2022 |
| Jojoha Invest AS | Real estate | 2018 |
| Jojuma Invest AS | | 2022 |
| Jok Holding AS | Real estate | 2005 |
| Jokama Invest AS | Financial services | 2018 |
| Joker Nord AS | Financial services | 2017 |
| Joker Sportscafé Da | Arts & recreation | 2008 |
| Jokerpotato AS | | 2020 |
| Jokersystemet AS | Information & communication | 2014 |
| Jokki X Holding AS | | 2026 |
| Jokki Y Holding AS | | 2026 |
| Jokr AS | Financial services | 2005 |
| Jokrijo Invest AS | Health & social care | 2023 |
| Jolawe Holding AS | | 2026 |
| Jolica AS | Financial services | 1996 |
| Jolima AS | Professional & scientific | 2011 |
| Jollebing Ans | Wholesale & retail | 2008 |
| Jollestore Da | Wholesale & retail | 2021 |
| Jolosol Invest AS | Professional & scientific | 2020 |
| Jom Kapital AS | | 2021 |