| Infinite G AS | Professional & scientific | 2019 |
| Infraplan AS | Wholesale & retail | 2017 |
| Ingeniørteknikk AS | Construction | 1994 |
| Inkassator AS | Administrative & support | 1976 |
| Inmetix AS | Professional & scientific | 2005 |
| Innedekning AS | Professional & scientific | 2024 |
| Inside AS | Wholesale & retail | 1967 |
| Intek Holdings AS | Real estate | 1969 |
| Inter-Sun AS | Manufacturing | 1976 |
| Interiørverkstedet AS | Manufacturing | 2020 |
| Interlock AS | Professional & scientific | 2015 |
| Internettopplysningen AS | Information & communication | 2004 |
| Interrobang AS | Information & communication | 2024 |
| Inwestermoen AS | | 2024 |
| Ionity GmbH (Nuf) Nuf | Energy | 2017 |
| Iot Hardware AS | Information & communication | 2018 |
| Isak Transport Og Renhold AS | Transport & logistics | 2025 |
| Isbjørn Invest AS | Real estate | 2018 |
| Isno Holdning AS | | 2025 |
| Istanbul Fruktmarked AS | Wholesale & retail | 2024 |
| Itw Novadan Aps | Wholesale & retail | 2008 |
| Ivas Holding AS | Manufacturing | 2020 |
| Ja Bilmegling AS | Wholesale & retail | 2014 |
| Jabba Invest AS | Professional & scientific | 2020 |
| Jacaranda Holding AS | Real estate | 2019 |
| Jaeger-Hansen Investment Group AS | | 2019 |
| Jaken Invest AS | Information & communication | 1990 |
| Jam Montasje AS | Construction | 2017 |
| Jan Strandbakke Holding AS | | 2024 |
| Janas Velvære AS | Other services | 2017 |
| Jaws Deploy AS | Information & communication | 2024 |
| JB 1 Eiendom AS | Real estate | 2014 |
| Jbro Holding AS | | 2025 |
| Jeg Er Unik AS | Administrative & support | 2015 |
| Jejs AS | Professional & scientific | 2023 |
| Jellestadveien 1 Seksjon 10 AS | Real estate | 2022 |
| Jellestadveien 1 Seksjon 11 AS | Real estate | 2022 |
| Jellestadveien 1 Seksjon 13 AS | Real estate | 2022 |
| Jellestadveien 1 Seksjon 3 AS | Real estate | 2022 |
| Jellestadveien 1 Seksjon 4 AS | Real estate | 2022 |
| Jellestadveien 1 Seksjon 5 AS | Real estate | 2022 |
| Jellestadveien 1 Seksjon 6 AS | Real estate | 2022 |
| Jellestadveien 1 Seksjon 7 AS | Real estate | 2022 |
| Jensens Rørleggerservice AS | Construction | 2014 |
| Jerez Holding AS | Professional & scientific | 2004 |
| Jernbaneveien 16 AS | Real estate | 1998 |
| Jevne Holding AS | Administrative & support | 2019 |
| JHD Invest AS | Real estate | 2005 |
| JK Barber Avd. 8 AS | Other services | 2023 |
| JK Barber Drift AS | Other services | 2023 |
| JK Barber Holding AS | Other services | 2022 |
| JK Beauty Salon AS | Other services | 2019 |
| JK Shop AS | Wholesale & retail | 2020 |
| Jke Design Ski AS | Wholesale & retail | 2023 |
| JKV Utvikling AS | Professional & scientific | 2021 |
| Jl-Invest AS | Real estate | 2020 |
| JMP Holding AS | | 2014 |
| JMP Invest AS | Wholesale & retail | 2017 |
| Jobj Holding AS | Financial services | 2018 |
| Jobportal Norway AS | Professional & scientific | 2024 |
| Joda AS | Construction | 2015 |
| Jodam AS | Hospitality | 2025 |
| Johansen & Co. Produksjon AS | Manufacturing | 2014 |
| Jonas Aasberg Holding AS | | 2024 |
| Jvkrey Holding AS | | 2022 |
| K by Kaos Ski AS | Wholesale & retail | 2020 |
| K Jacobsen AS | Real estate | 1986 |
| K Jacobsen Entreprenør AS | Real estate | 2007 |
| K. Berg AS | Education | 1995 |
| K12X Invest AS | Administrative & support | 2022 |
| K12X MC Adventure AS | Administrative & support | 2022 |
| Ka Konsult AS | Professional & scientific | 2013 |
| Kaffepause AS | Hospitality | 2025 |
| Kaizen Nova AS | Transport & logistics | 2024 |
| Kaizen Shipping AS | Transport & logistics | 2025 |
| Kaizer Invest AS | | 2021 |
| Kamin Eiendom Askim AS | Real estate | 2015 |
| Kaminar AS | | 2022 |
| Kampenes Holding AS | Information & communication | 2025 |
| Kapa AS | Administrative & support | 2018 |
| Kapitalens Krokodiller AS | | 2018 |
| Karlsrud Skog Ans | Agriculture & fishing | 1996 |
| KASE AS Oslo | Wholesale & retail | 1988 |
| Kbps Entreprenør AS | Construction | 2026 |
| KC Follo AS | Wholesale & retail | 2011 |
| Kebabhouse Ski AS | Hospitality | 2018 |
| Keco AS | Professional & scientific | 2017 |
| Kelstrup Invest AS | | 2021 |
| Kenno AS | Wholesale & retail | 2019 |
| Keramo AS | Construction | 2024 |
| Kesk Holding AS | | 2025 |
| KG Ellinggard Holding AS | Real estate | 2013 |
| KGK Norge AS | Wholesale & retail | 1979 |
| Kgo Invest AS | | 2005 |
| Kile Markedshage AS | Agriculture & fishing | 2023 |
| Kilkaya AS | Information & communication | 2020 |
| Kilsbakken Boligutvikling AS | Real estate | 2017 |
| Kimen Såvarelaboratoriet AS | Professional & scientific | 2004 |
| Kinoa Gruppen AS | | 2024 |
| Kinoa Tiltak AS | Health & social care | 2018 |