| Kosmos 4 Eiendomsselskap AS | Real estate | 2003 |
| Kosthjelpen AS | Health & social care | 2020 |
| Kov Consult AS | Professional & scientific | 2013 |
| KPL AS | Professional & scientific | 2020 |
| Krabbesund AS | Real estate | 2021 |
| Kraftir AS | Energy | 2018 |
| Kran Og Transportservice AS | Transport & logistics | 2019 |
| Krankel Zeptus AS | Real estate | 2005 |
| Krankonsult AS | Manufacturing | 2023 |
| Kranmesteren AS | Transport & logistics | 2019 |
| Kras Auto AS | Other services | 2024 |
| Kreative Kurs Sandefjord AS | Education | 2017 |
| Kremeriet AS | Wholesale & retail | 2024 |
| Krisbygg AS | Construction | 2019 |
| Kristelle Eiendom AS | Real estate | 2004 |
| Kristian Klaveness Holding AS | | 2020 |
| Kristiansen Håvard Fysioterapi AS | Health & social care | 1996 |
| Kristiansen Optik AS | Wholesale & retail | 2008 |
| Kristiansen Ur Og Gull AS | Wholesale & retail | 1996 |
| Kristine Masdal Aadne AS | Information & communication | 2024 |
| Kristjansson Malerservice AS | Construction | 2020 |
| Kristoffer Andersen AS | Wholesale & retail | 2011 |
| Kristoffersen Holdingselskap AS | | 2019 |
| Kristoffersen Salg Og Service AS | Manufacturing | 2024 |
| Kriva AS | Manufacturing | 1979 |
| Krogholm AS | | 2019 |
| Krohn-Olsen AS | Administrative & support | 2005 |
| Krokemoveien 126 AS | Real estate | 2016 |
| Kroken Bigård AS | Wholesale & retail | 1989 |
| Krokusen Barnehage AS | Education | 2005 |
| Krokusveien 9 AS | Real estate | 2016 |
| Kronblad Blomster AS | Wholesale & retail | 2025 |
| Kronstad Bygg Og Eiendom AS | Real estate | 2023 |
| Kronstad Byggtjenester AS | Construction | 2023 |
| Kronstad Forvaltning AS | | 2024 |
| Kronstad Kapital AS | Real estate | 2023 |
| Krontech AS | Wholesale & retail | 2000 |
| Krossnic AS | Real estate | 1998 |
| Krost AS | Real estate | 2022 |
| Kråka Holding AS | Financial services | 2016 |
| Kråkåsveien 1 AS | Real estate | 2016 |
| Krüger Kaldnes AS | Manufacturing | 1989 |
| KTB Drift Og Service AS | Real estate | 2021 |
| Kulde Og Varmeteknikk AS | Construction | 2001 |
| Kullerød Eiendomsinvest AS | Real estate | 2006 |
| Kultur I Hagan AS | Administrative & support | 2017 |
| Kulturmeieriet AS | Professional & scientific | 2017 |
| Kultursupport AS | Administrative & support | 1997 |
| Kumera Marine AS | Manufacturing | 1965 |
| Kurt Bygg AS | Construction | 2020 |
| KV Thomassen Invest AS | Financial services | 2013 |
| Kval Consultancy Services Ltd Nuf | Information & communication | 2010 |
| Kvamme Produktutvikling AS | Professional & scientific | 2018 |
| Kvartal 19 AS | Real estate | 1996 |
| L&D Holding AS | | 2019 |
| L&T Bredal Invest AS | Professional & scientific | 2014 |
| L.L. Service AS | Construction | 2023 |
| La Scala AS | Real estate | 2005 |
| Lacca Holding AS | Wholesale & retail | 2020 |
| Lady & Landstryker'N Restauranthus AS | Hospitality | 2007 |
| Lafteboys AS | Manufacturing | 2023 |
| Lagspiller AS | Professional & scientific | 2024 |
| Lahelle AS | Real estate | 2019 |
| Lahelle Barnehage AS | Education | 2023 |
| Lahelle Eiendom AS | Real estate | 2024 |
| Lali Invest AS | | 2022 |
| Lamadoso AS | Wholesale & retail | 2025 |
| Lana Eiendom AS | Real estate | 2005 |
| Landskapskollektivet AS | Professional & scientific | 2018 |
| Landstadsgate 10 AS | Real estate | 2019 |
| Landstryker'N Reiser AS | Administrative & support | 2007 |
| Langeby AS | Real estate | 2004 |
| Langeby Camping AS | Hospitality | 2018 |
| Langes Gate 12 AS | Real estate | 2025 |
| Langes Gate 8 AS | Real estate | 2025 |
| Langfeldt Holding AS | | 2021 |
| Langfjord Holding AS | Financial services | 2010 |
| Langsethagen Invest AS | | 2023 |
| Langøytangen Bidco AS | | 2023 |
| Laplace Holding AS | | 2026 |
| Larger Harvest AS | Professional & scientific | 2024 |
| Larkin Holding AS | Manufacturing | 2005 |
| Lars Morten Eid Holding AS | | 2025 |
| Lars Strømme Invest AS | Real estate | 2005 |
| Larsen Invest AS | Real estate | 1978 |
| Larsen Rekruttering Og Salgstjenester AS | Administrative & support | 2012 |
| Larsens Vann & Varme AS | Construction | 1995 |
| Larsing AS | Financial services | 2006 |
| Larvik Bilutleie AS | Administrative & support | 2016 |
| Larvik Eiendomsinvest AS | Real estate | 2018 |
| Lask Invest AS | | 2025 |
| Lasken AS | Real estate | 2023 |
| Lasken Holding AS | Financial services | 2013 |
| Lasken Invest AS | | 2019 |
| Laskenveien 36 B AS | Transport & logistics | 2014 |
| Lasse Solberg Invest AS | Construction | 2005 |
| Lastein Eiendom AS | Real estate | 2012 |
| Lathor AS | Financial services | 2005 |
| Lathor Eiendom AS | Real estate | 2020 |
| Lativ Tomter AS | Real estate | 1994 |