| Høvik Argos Holding AS | Professional & scientific | 1997 |
| Høvik AS | Real estate | 1998 |
| Høvik Eiendomsdrift AS | Administrative & support | 2002 |
| Høvik Gård AS | Agriculture & fishing | 2017 |
| Iaap AS | Health & social care | 2013 |
| Iby AS | Administrative & support | 1991 |
| Iby Service AS | Professional & scientific | 2022 |
| Ihla Samdrift Da | Agriculture & fishing | 2005 |
| Illari AS | Financial services | 2005 |
| Impetus Property Finance AS | Professional & scientific | 2020 |
| In Too Deep AS | Financial services | 2014 |
| Industriagentur Ans | | 1990 |
| Inge a. Aasen AS | | 2005 |
| Inger Nedal Invest | | 2024 |
| Innovative Management Services AS | Administrative & support | 1998 |
| Insert Solution AS | Professional & scientific | 2002 |
| Inweston AS | Real estate | 2013 |
| Ioslo Rådgivning AS | Professional & scientific | 2014 |
| Ivation Invest AS | Professional & scientific | 2011 |
| JA9 Invest AS | | 2018 |
| Jacobsen Elektro AS | Professional & scientific | 2019 |
| Jafu Holding AS | Financial services | 2005 |
| Jan Anders Marheim AS | Professional & scientific | 2013 |
| Japa Bygg AS | Construction | 2011 |
| Japa Bygg Holding AS | Construction | 2020 |
| Japa Bygg Invest AS | Construction | 2020 |
| JBC AS | Administrative & support | 2016 |
| Jerico Holding AS | Professional & scientific | 2019 |
| Jesusislord AS | | 2026 |
| JF Maskin AS | Construction | 2015 |
| JFT Estetikk AS | Other services | 2026 |
| JG Bygg Og Rehabilitering AS | Construction | 2025 |
| Jit Holding AS | Administrative & support | 2005 |
| Jit Tjenester AS | Administrative & support | 2018 |
| Jodal Holding AS | Financial services | 2016 |
| Joffen Invest AS | | 2024 |
| Jofix AS | Administrative & support | 2011 |
| John Volden Holding AS | Financial services | 2007 |
| Joint-Venture Holding AS | | 2020 |
| Jolin Accounting AS | Professional & scientific | 2015 |
| Jonia AS | | 2025 |
| Jonsson Folkestad Software AS | Information & communication | 2001 |
| Jordbærkollen Holding AS | Real estate | 2013 |
| JRF Holding AS | | 2025 |
| JST Tak Og Blikk AS | Construction | 2023 |
| Julin Råd AS | Professional & scientific | 2022 |
| Jumili AS | | 2022 |
| Jåla AS | Financial services | 2005 |
| Jåle AS | Professional & scientific | 1995 |
| K&H Holding AS | Health & social care | 2024 |
| K-Dalens Service Limited Nuf | Professional & scientific | 2009 |
| K3 Flis & Våtrom AS | Construction | 2017 |
| Ka Bil AS | Wholesale & retail | 2022 |
| Kabh Holding AS | | 2025 |
| Kai Svendsen Holding AS | Financial services | 2007 |
| Kalmo Gård AS | Arts & recreation | 2016 |
| Kalsvogna AS | Transport & logistics | 2006 |
| Kambygg Viken AS | Construction | 2021 |
| Kd-Staalkraft AS | Wholesale & retail | 2025 |
| Kemper Invest AS | Administrative & support | 2019 |
| Key Dog AS | Wholesale & retail | 2005 |
| Key IT AS | Wholesale & retail | 2001 |
| Keylink AS | Wholesale & retail | 2023 |
| KG Eiendom AS | Real estate | 2010 |
| KHS Maskin AS | Construction | 2018 |
| Kif Holding AS | Wholesale & retail | 2006 |
| Kikut Produksjon AS | Agriculture & fishing | 2008 |
| Kikutveien 5 AS | Real estate | 1998 |
| Kiropraktor Kristian Gabrielsen AS | Health & social care | 2017 |
| Kjetil Ellefsen Holding AS | Financial services | 2009 |
| Kjetil Halden Invest AS | Real estate | 2018 |
| KKB AS | | 2024 |
| Knutson Incentiv AS | Arts & recreation | 2016 |
| Kogstad AS | Administrative & support | 1997 |
| Kollekta AS | Wholesale & retail | 2023 |
| Kompani OSS2 AS | | 2021 |
| Kompani VI2 AS | Transport & logistics | 2021 |
| Kongsberg Park AS | Real estate | 2016 |
| Konsernet Mortensen AS | Construction | 2005 |
| Kontrollert Atmosfære Lager Lier AS | Transport & logistics | 2000 |
| Korsvik Engineering Nuf | Professional & scientific | 2007 |
| Kortnes Gartneri AS | Agriculture & fishing | 2001 |
| Kortnes Hyttegrend AS | Hospitality | 1984 |
| Kortnes Maskin AS | Other services | 1988 |
| Kotek Norge AS | Professional & scientific | 2002 |
| Kraftkar AS | Real estate | 2014 |
| Kranoperatøren AS | Construction | 2024 |
| Krikir Invest AS | | 2022 |
| Kris Autotrading Da | Wholesale & retail | 1998 |
| Kristine Hegg AS | Professional & scientific | 2023 |
| Kulelagerhuset AS | Wholesale & retail | 1998 |
| Kyberax AS | Information & communication | 2025 |
| L Regnskap AS | Professional & scientific | 2026 |
| LA8PV AS | Real estate | 2022 |
| Lana Vela AS | Wholesale & retail | 2025 |
| Lbas AS | Real estate | 2002 |
| Legacy in Stone AS | Mining & quarrying | 2024 |
| Lehmkuhl AS | Manufacturing | 1998 |
| Lerungskogen Vann- Og Avløp Drift SA | Water & waste | 2020 |
| Lerungskogen Vann- Og Avløpslag SA | Construction | 2020 |