| Joytrack AS | Professional & scientific | 2011 |
| JP Drift AS | | 2025 |
| JP Rosenlund AS | Real estate | 2016 |
| Jpeg AS | Arts & recreation | 2023 |
| Jpkj Capital AS | | 2025 |
| Jpmd Holding AS | Real estate | 2015 |
| JPN AS | Hospitality | 2017 |
| JPT Holding AS | Financial services | 2012 |
| Jqrgencorp Holding AS | | 2021 |
| JR Future Bygg AS | Construction | 2023 |
| JR Mur Og Bygg AS | Construction | 2022 |
| JR Rishaug AS | | 2023 |
| Jra Adventure AS | | 2023 |
| JRH AS | | 2019 |
| JRJ Bygg AS | Construction | 2018 |
| JS Communication AS | Professional & scientific | 2021 |
| JS Company AS | Wholesale & retail | 2019 |
| Jsa Investments AS | | 2021 |
| Jsbboss Holding AS | | 2024 |
| JSG Norge AS | Professional & scientific | 2023 |
| Jstarkitekter AS | Professional & scientific | 2007 |
| Jsy AS | Administrative & support | 2010 |
| JTF AS | Hospitality | 2015 |
| Jub AS | Financial services | 2013 |
| Juba Juba AS | Administrative & support | 2014 |
| Jugenddronninga AS | Real estate | 2024 |
| Juke AS | Information & communication | 2020 |
| Julcat AS | Professional & scientific | 2005 |
| Juletregården Breivika AS | Agriculture & fishing | 2012 |
| Julia Wiel | Professional & scientific | 2022 |
| Juliahub Norway AS | Information & communication | 2024 |
| Julianus Holms Veg 34 AS | Real estate | 2020 |
| Julije Holding AS | | 2021 |
| Julius AS | Professional & scientific | 2023 |
| Juliussen Consulting AS | Professional & scientific | 2019 |
| Juliussen Invest AS | Professional & scientific | 2006 |
| Julmas AS | Financial services | 2005 |
| Juma Development Ltd Nuf | Information & communication | 2012 |
| Juma Holding AS | Wholesale & retail | 2005 |
| Jumar AS | Real estate | 2018 |
| Jump Club AS | Wholesale & retail | 2008 |
| Jungel AS | Hospitality | 2023 |
| Junior Consulting AS | Professional & scientific | 2012 |
| Junor Invest AS | Professional & scientific | 2008 |
| Jurita AS | | 2024 |
| Just Gonna Send IT AS | | 2025 |
| Justfly AS | Administrative & support | 2013 |
| Jutvika Utbygging AS | Real estate | 2012 |
| JV Demolering AS | Construction | 2010 |
| Jviken Holding AS | | 2021 |
| JVS Bygg AS | Construction | 2026 |
| JWD Holding AS | | 2024 |
| JWH AS | | 2021 |
| JWR Holding AS | Real estate | 2019 |
| Jyh AS | | 2025 |
| Jølle & Kristensen AS | Construction | 2016 |
| Jølle & Kristensen Holding AS | Construction | 2024 |
| Jønestål AS | | 2024 |
| Jørgen Rødli Holding AS | Real estate | 2003 |
| Jørgensen Invest Holding AS | | 2017 |
| Jørn Rørmark AS | Professional & scientific | 2018 |
| Jøsnøya Eiendom AS | Real estate | 2024 |
| Jøssund Eiendom AS | Real estate | 2011 |
| K Dahl Invest AS | Financial services | 2005 |
| K Kvalø AS | Transport & logistics | 2020 |
| K Lund AS | Construction | 1964 |
| K-To AS | | 2014 |
| K. Aa Holding AS | Real estate | 2007 |
| K. Utvikling AS | Real estate | 2022 |
| K.D. Feddersen Plastics Machinery AS | Wholesale & retail | 2015 |
| K.E. Holding AS | | 2005 |
| K.E.Bergersen AS | Health & social care | 2025 |
| K/M/T AS | | 2007 |
| K2 Trading AS | Information & communication | 2017 |
| K3 Kiropraktorklinikk AS | Health & social care | 2016 |
| K5 Invest AS | Wholesale & retail | 2005 |
| Ka Blikk AS | Construction | 2024 |
| KA11 Holding 2 AS | | 2025 |
| Kaare Olsen Invest AS | | 2020 |
| Kabano AS | | 2025 |
| Kabokart AS | Professional & scientific | 2017 |
| Kadabra AS | Professional & scientific | 2024 |
| Kaelthas AS | | 2025 |
| Kaern AS | Professional & scientific | 2025 |
| Kaern Development AS | Mining & quarrying | 2025 |
| Kaern Solutions AS | Mining & quarrying | 2025 |
| Kafe Larsen AS | Hospitality | 2000 |
| Kafe to Tårn AS | Hospitality | 2018 |
| Kaffe Compagniet AS | Wholesale & retail | 1991 |
| Kaffemannen AS | | 2019 |
| Kafékollektivet AS | Hospitality | 2011 |
| Kagaflow AS | | 2025 |
| Kahg Areal AS | Real estate | 2019 |
| Kai Holding AS | | 2019 |
| Kaigata 3-5 AS | Real estate | 2008 |
| Kaireg AS | Wholesale & retail | 2021 |
| Kajo Assets Management AS | | 2026 |
| Kajsa Hårstad AS | Other services | 2023 |
| Kajsa Kajsa Da | Wholesale & retail | 2020 |
| Kaks Invest AS | | 2023 |