| JRR Invest AS | | 2026 |
| JSJ Holding AS | | 2021 |
| JSK AS | | 2020 |
| JT Solutions Da | Information & communication | 2012 |
| Jtgled AS | | 2020 |
| Jtha Invest AS | | 2015 |
| Juan Sushi AS | Hospitality | 2021 |
| Juel Johannessen Glass Ans | Construction | 1989 |
| Juel Johannessen Glassforretning AS | Construction | 2019 |
| Juli Invest AS | Financial services | 1996 |
| Jump AS | Professional & scientific | 2012 |
| Jumpmediagroup AS | Information & communication | 2000 |
| Junjin Norge AS | Wholesale & retail | 2007 |
| Justor Da | Health & social care | 2018 |
| Justus Prosjekt AS | Professional & scientific | 2025 |
| Juthophi AS | | 2025 |
| Juvik Service AS | Construction | 2011 |
| Jvmt AS | Construction | 2022 |
| Jøhans AS | | 2020 |
| Jøran Olafsen Holding AS | | 2022 |
| Jørgen Johansen Holding AS | | 2026 |
| K M Invest AS | Real estate | 1988 |
| K.O.Roe AS | Financial services | 2016 |
| K2 Utleie Da | Administrative & support | 2023 |
| Ka Transport & Montasje AS | Transport & logistics | 2013 |
| Kab AS | Professional & scientific | 2005 |
| Kabrettstea AS | Real estate | 2005 |
| Kad Consult AS | Professional & scientific | 2026 |
| Kaehan AS | Real estate | 2016 |
| Kafka Sandefjord AS | Hospitality | 2011 |
| Kaiso Sustainable Solution AS | Professional & scientific | 2021 |
| Kajs Invest AS | Arts & recreation | 2020 |
| Kakeboksen Holding AS | | 2020 |
| Kalpa Holding AS | | 2022 |
| Kamfjord Industrier AS | Real estate | 1974 |
| Kanalen Eiendom AS | Real estate | 2005 |
| Kanalparken AS | Real estate | 2005 |
| Kanit AS | Information & communication | 2011 |
| Kap Adare AS | Information & communication | 2004 |
| Kapital Eiendom AS | Real estate | 2022 |
| Kapital Holding AS | Real estate | 2023 |
| Kapital Prosjekt 1 AS | Real estate | 2026 |
| Kapital Utvikling AS | Administrative & support | 2022 |
| Kappa Revisjon Ans | Professional & scientific | 2003 |
| Kappa Revisjon AS | Professional & scientific | 2004 |
| Karantz AS | Information & communication | 2021 |
| Karat Engros AS | Real estate | 1990 |
| Kardiokonsult AS | Health & social care | 1990 |
| Kari Uri AS | Professional & scientific | 2023 |
| Karin Rød AS | Health & social care | 2011 |
| Karis Salong AS | Other services | 2015 |
| Karis Salong by Gosia AS | Other services | 2026 |
| Karl & Co Invest AS | Real estate | 2006 |
| Karl Filip AS | Real estate | 2021 |
| Karl J Svensen AS | Construction | 2005 |
| Karlsen Transport & Eiendom AS | Transport & logistics | 1999 |
| Karma Hudpleie Da | Other services | 2002 |
| Karna Holding AS | Real estate | 2005 |
| Karo-Invest AS | Financial services | 2005 |
| Karriereportalen AS | Education | 2026 |
| Karrismatic Invest AS | | 2020 |
| Karsten Meum AS | Construction | 2019 |
| Kartotech AS | | 2020 |
| Katch AS | Information & communication | 2026 |
| Kaupang Holding AS | | 2024 |
| KB Invest AS | Professional & scientific | 1988 |
| KB Prosjekt 1 AS | Real estate | 2020 |
| Kebmar AS | Professional & scientific | 1998 |
| Kefas AS | Information & communication | 2022 |
| Kelinor Group AS | Professional & scientific | 2022 |
| Kenson AS | Wholesale & retail | 2015 |
| Keramikk Norge AS | Wholesale & retail | 2026 |
| Kesar AS | Hospitality | 2018 |
| Kevin Andersen Invest AS | Construction | 2025 |
| Kevin Larsen Invest AS | Wholesale & retail | 2020 |
| Key Invest AS | Real estate | 2021 |
| Key Performance Systems AS | Information & communication | 2014 |
| Keyq Group AS | Wholesale & retail | 2017 |
| KFC Holding AS | Other services | 2023 |
| Kicamp AS | Hospitality | 2015 |
| Kildemor AS | Real estate | 2013 |
| Kilen Apotek AS | Wholesale & retail | 2004 |
| Kilen Bensin AS | Wholesale & retail | 1990 |
| Kilen Brygge 1 AS | Real estate | 2017 |
| Kilen Brygge Restaurant AS | Hospitality | 2009 |
| Kilen Fysioterapi Og Akupunktur AS | Health & social care | 2025 |
| Kilen Holding AS | Real estate | 2005 |
| Kilen Hår & Velvære AS | Other services | 2009 |
| Kilen Kiropraktikk AS | Health & social care | 2020 |
| Kilen Legesenter Da | Health & social care | 2007 |
| Kilen Rør AS | Construction | 2015 |
| Kilen Tannlegesenter AS | Health & social care | 2002 |
| Kilimanjaro Invest AS | Financial services | 2023 |
| Kim Og Sigves Rakettutsalg AS | Wholesale & retail | 2021 |
| Kims Corner Da | Wholesale & retail | 1989 |
| Kind Eiendom AS | Real estate | 2016 |
| Kind Energispar AS | Construction | 2007 |
| Kingpin AS | Arts & recreation | 2005 |
| Kinzy Group AS | Professional & scientific | 2024 |
| Kiriv Invest AS | | 2019 |