| Janaflaten Næringspark AS | Real estate | 2019 |
| Janeli AS | Financial services | 2007 |
| Jani AS | Real estate | 2002 |
| Janil Invest AS | | 2005 |
| Janma AS | Real estate | 2005 |
| Jaraad AS | Real estate | 2023 |
| Jarbtech Solution Group AS | Information & communication | 2013 |
| Jarico Invest AS | Financial services | 2012 |
| Jaro Gruppen AS | Real estate | 1996 |
| Jashan Restaurant AS | Hospitality | 2019 |
| Jaso Holding AS | Professional & scientific | 2005 |
| Jason AS | Financial services | 1996 |
| Javipa AS | Real estate | 1981 |
| Javiste AS | | 2024 |
| Jawendel AS | Professional & scientific | 2001 |
| Jbo AS | Real estate | 2005 |
| JBS Jansen Broadcast Support AS | Wholesale & retail | 2006 |
| JCC Holding AS | | 2020 |
| JCK AS | Education | 2009 |
| JCK Capital AS | Financial services | 2017 |
| JDM Invest No AS | Real estate | 2022 |
| JDM Real Estate No AS | Real estate | 2020 |
| Jebsen Carriers Ltd | Transport & logistics | 1995 |
| Jebsen Group AS | Transport & logistics | 2009 |
| Jeessaa AS | Professional & scientific | 2007 |
| Jeggis AS | Wholesale & retail | 2018 |
| Jej Norge Invest AS | Manufacturing | 2012 |
| Jem Invest AS | Real estate | 1992 |
| Jen Invest AS | Real estate | 2005 |
| Jenny Hagen AS | Arts & recreation | 2022 |
| Jenny Marie Bjørndal AS | | 2021 |
| Jens CHR Berle AS | Wholesale & retail | 1992 |
| Jens Restaurant AS | Hospitality | 2021 |
| Jensen Flis & Fasade AS | Construction | 2013 |
| Jentoft Holding AS | Construction | 2005 |
| Jeppesen Eiendom AS | Real estate | 1999 |
| Jerbj AS | | 2019 |
| Jernstøperiet AS | Real estate | 2013 |
| Jes-Holding AS | Real estate | 2019 |
| JES1 AS | | 2020 |
| Jets Holding AS | Real estate | 2011 |
| Jeyman AS | | 2023 |
| JFF AS | Professional & scientific | 2018 |
| JFN AS | Financial services | 2011 |
| JGD Invest AS | Financial services | 2005 |
| JH Innovation AS | Wholesale & retail | 2023 |
| JH Kardio Holding AS | | 2023 |
| JH Tech & Invest AS | Professional & scientific | 2018 |
| JH2 Holding AS | | 2024 |
| JHB Holding AS | | 2021 |
| Ji Thomassen Regnskap AS | Professional & scientific | 2017 |
| Jib Holding AS | | 2021 |
| Jisj Holding AS | Information & communication | 2019 |
| Jjh-Katla Holding AS | Professional & scientific | 2022 |
| JK - Invest AS | Professional & scientific | 2002 |
| JK Language Services Ans | Education | 2004 |
| Jkmu Holding AS | Financial services | 2012 |
| JMG Holding AS | | 2013 |
| JMT Nordic AS | Professional & scientific | 2013 |
| JMV Holding AS | Financial services | 2017 |
| Jnhp Holding AS | | 2023 |
| Jo Gjerstad Kulturformidling AS | Education | 2015 |
| Jo Odfjell AS | Transport & logistics | 2015 |
| Jo Sand AS | Health & social care | 2023 |
| JO2 Holding AS | | 2025 |
| Joachim Grieg Partners AS | Transport & logistics | 2010 |
| Joachim WG AS | | 2018 |
| Joanna's Art Club AS | Arts & recreation | 2026 |
| Jobb I Bergen AS | Administrative & support | 2006 |
| Jobby AS | Real estate | 2019 |
| Jobby II AS | Professional & scientific | 2022 |
| Jobby X AS | | 2024 |
| Jobloop AS | Education | 2017 |
| Jobwell AS | Education | 2020 |
| Jof Forvaltning AS | Financial services | 2017 |
| Jofi AS | Professional & scientific | 2018 |
| Johakri AS | Financial services | 2005 |
| Johan Berentsensvei 63 AS | Real estate | 1992 |
| Johan Berentsensvei 65 AS | Real estate | 2006 |
| Johan Eek-Larsen AS | Construction | 1977 |
| Johan Troye AS | Real estate | 1935 |
| Johannesen Dagligvare AS | Wholesale & retail | 2019 |
| Johannesen Holding AS | | 2026 |
| Johannessen & Ljone Finans AS | Professional & scientific | 1994 |
| Johansson Konsulent & Rådgivning AS | Professional & scientific | 1992 |
| John-Andre Flåm AS | Wholesale & retail | 2014 |
| John-Henry Erstad AS | | 2010 |
| Joho Forvaltning AS | | 2026 |
| Joho Invest AS | Financial services | 2006 |
| Jokernord AS | Real estate | 2016 |
| Jollyoo Corporate AS | Wholesale & retail | 2024 |
| Jollyroger AS | Transport & logistics | 2025 |
| Jon Smørs Gate Eiendom AS | Real estate | 2013 |
| Jonas Foss Holding AS | | 2021 |
| Jonas Reinsgate 15 a AS | Real estate | 2015 |
| Jonas Reinsgate 9B AS | Real estate | 2019 |
| Jonasson Invest AS | | 2026 |
| Jonge Eiendom AS | Real estate | 2026 |
| Jonge Holding AS | Professional & scientific | 2023 |
| Joni Invest AS | Financial services | 2005 |