| Kjørbekkdalen 14 AS | Real estate | 1985 |
| Kjørbekkdalen 19 AS | Real estate | 2015 |
| Kjørbekkdalen 5 Skien AS | Real estate | 2005 |
| Kjørbekkdalen 8 AS | Real estate | 1981 |
| Kjørboparken AS | Real estate | 2005 |
| Kjøre- Og Hviletidshjelperen AS | Professional & scientific | 2020 |
| Kjøregår AS | | 2020 |
| Kjørmednorge AS | Information & communication | 2025 |
| Kjøtåa Kraftverk AS | Energy | 2025 |
| KK Capital AS | | 2026 |
| KK Gyn AS | Health & social care | 2020 |
| KK Property AS | Real estate | 2021 |
| KK Rådgivning AS | Professional & scientific | 2025 |
| KK Rør AS | Construction | 2019 |
| KK Supplies AS | Wholesale & retail | 2022 |
| KKH AS | | 2022 |
| Kki Invest AS | Professional & scientific | 2012 |
| KKJ Holding AS | | 2022 |
| KKJ Kapital AS | | 2024 |
| KKN Equity AS | Financial services | 2009 |
| KKN Invest AS | Financial services | 2009 |
| KKR Invest AS | Information & communication | 2016 |
| KKV AS | Real estate | 2018 |
| KL Consulting AS | Professional & scientific | 2022 |
| KL Equity AS | Professional & scientific | 2025 |
| KL Helse AS | Health & social care | 2022 |
| KL Management AS | Professional & scientific | 2024 |
| KL Oslo AS | | 2018 |
| KL Prosjektutvikling Da | Real estate | 2009 |
| Kl-Bygg Viken AS | Construction | 2022 |
| KL1 Invest AS | | 2024 |
| Klaasen Holding AS | | 2024 |
| Klab Holding AS | Construction | 2024 |
| Klakegg Consulting AS | Information & communication | 2020 |
| Klami Consulting AS | Professional & scientific | 2018 |
| Klampe AS | Financial services | 2023 |
| Klan-Eiendom AS | Real estate | 2014 |
| Klang Av Oldtid Da | Arts & recreation | 2016 |
| Klangfarge AS | Professional & scientific | 2022 |
| Klanten Holding AS | | 2021 |
| Klar Bolig AS | Real estate | 2023 |
| Klar Entreprise AS | Construction | 2016 |
| Klar Ferdig Selg AS | Professional & scientific | 2026 |
| Klar Holdning AS | Construction | 2022 |
| Klar Invest AS | | 2015 |
| Klar Psykologklinikk AS | Health & social care | 2026 |
| Klar Renhold AS | Administrative & support | 2025 |
| Klar Topco AS | | 2025 |
| Klara Holding AS | Arts & recreation | 2017 |
| Klare Hoder AS | Other services | 2013 |
| Klarere AS | Professional & scientific | 2022 |
| Klarkraft AS | Energy | 2014 |
| Klarluft AS | Construction | 2026 |
| Klarna Norge AS | Professional & scientific | 2010 |
| Klarna Technologies AS | Information & communication | 2014 |
| Klarsol Energi AS | Construction | 2024 |
| Klarvi AS | Information & communication | 2026 |
| Klarvinduer AS | Construction | 2021 |
| Klassekampen AS | Information & communication | 1975 |
| Klasserommet AS | Hospitality | 2019 |
| Klassiske Bygårder AS | | 2026 |
| Klatre Invest AS | Financial services | 2017 |
| Klatreeventyr AS | Administrative & support | 2018 |
| Klatrehuset AS | Arts & recreation | 2019 |
| Klatreverket AS | Arts & recreation | 2006 |
| Klatt Ans | Construction | 2013 |
| Klauabekk AS | Financial services | 2018 |
| Klauper Holding AS | | 2026 |
| Klaus Hennum Produksjon AS | Professional & scientific | 2005 |
| Klaus Invest AS | Real estate | 2004 |
| Klausmikkelsen AS | Professional & scientific | 2024 |
| Klauva Kraft AS | Energy | 2012 |
| Klaveneslåven AS | Real estate | 1980 |
| Klaveness AS | Transport & logistics | 2011 |
| Klaveness Asia Pte. Ltd. | Transport & logistics | 2016 |
| Klaveness Combination Carriers ASA | Transport & logistics | 2018 |
| Klaveness Digital AS | Information & communication | 2017 |
| Klaveness Dry Bulk AS | Transport & logistics | 2021 |
| Klaveness Finans AS | Transport & logistics | 2008 |
| Klaveness Invest AS | Transport & logistics | 2005 |
| Klaveness Maler- Og Byggmester- Forretning AS | Construction | 2004 |
| Klaveness Marine Finance AS | Administrative & support | 2011 |
| Klaveness Marine Holding AS | Administrative & support | 2011 |
| Klaveness Ship Investments AS | Transport & logistics | 2005 |
| Klaveness Ship Management AS | Transport & logistics | 2011 |
| Klavetica AS | | 2026 |
| Klax Holding AS | | 2020 |
| Klaxton AS | Wholesale & retail | 2018 |
| KLC AS | Professional & scientific | 2020 |
| Klco Invest AS | Professional & scientific | 2011 |
| KLD AS | Hospitality | 2018 |
| Klean Kode AS | Water & waste | 2026 |
| Klebex AS | Real estate | 2025 |
| Kleda Gruppen AS | Information & communication | 2024 |
| Kleenerr AS | Administrative & support | 2022 |
| Klehe Invest AS | | 2021 |
| Kleiberg & Co AS | Professional & scientific | 2019 |
| Klein AS | Real estate | 2005 |
| Klein Boligeiendom 10 AS | Real estate | 2021 |
| Klein Boligeiendom 15 AS | Real estate | 2022 |