| Kirkebakken Bilverksted Ans | Other services | 1988 |
| Kirkerudåsen Utbygningsselskap AS | Real estate | 1989 |
| Kit Interiørarkitektur AS | Professional & scientific | 2016 |
| KJ Gruppen AS | Education | 2019 |
| KJ NFG Holding AS | Real estate | 2023 |
| Kjeppestadveien 4 AS | Real estate | 1985 |
| Kjeppestadveien 44 AS | Real estate | 2016 |
| Kjerag Labs AS | Professional & scientific | 2024 |
| Kjetil Schau AS | | 2026 |
| Kjeveortoped Espen Dahl AS | Health & social care | 2008 |
| Kjølstad Drift Da | Agriculture & fishing | 2021 |
| Kjønnås & Co Holding AS | Agriculture & fishing | 1992 |
| Kjøreglede Auto AS | Other services | 2025 |
| KK Ski AS | Wholesale & retail | 2026 |
| KK88.NO AS | Information & communication | 1995 |
| Klaastad AS | Financial services | 2005 |
| Kleggen Invest AS | | 2024 |
| Knallgod Invest AS | | 2025 |
| Knoll Og Tott Ans | Wholesale & retail | 1992 |
| Ko-Ma AS | | 2023 |
| Kokrisi Holding AS | | 2017 |
| Kolbotn Glasservice Invest AS | Wholesale & retail | 2013 |
| Kolbotn Karosseri & Lakk AS | Other services | 1997 |
| Kort & Kort Da | Manufacturing | 2006 |
| Kreativgården AS | Real estate | 2007 |
| Kribry Holding AS | | 2022 |
| Kringsjå Grendelag SA | Other services | 1985 |
| Krisan Holding AS | Professional & scientific | 2024 |
| Kristiania Bil AS | Wholesale & retail | 2019 |
| Kroko AS | | 2018 |
| Krunsj AS | Hospitality | 2023 |
| Krysset Eiendom AS | Real estate | 2018 |
| Krystall Byggservice AS | Construction | 2014 |
| Kråkstadveien 90 AS | Real estate | 2021 |
| KSM69 AS | | 2021 |
| KSR Eiendom AS | Professional & scientific | 2012 |
| Kurs I Skolen AS | Education | 2023 |
| Kvagas AS | | 2026 |
| Kvakestad Planteskole AS | Agriculture & fishing | 1993 |
| Kvakkestad & Sønner AS | Construction | 1961 |
| Kvakkestadgården 3 Ans | Real estate | 1993 |
| Kvakkestadgårdene AS | Real estate | 2019 |
| Kvalsund Holding AS | | 2026 |
| Kvarstein AS | Wholesale & retail | 2005 |
| Kvarving Invest AS | | 2025 |
| Kvistås Entreprenør AS | Construction | 2024 |
| Kånn to AS | Information & communication | 2024 |
| Kåpe AS | Administrative & support | 2016 |
| L/S Holding AS | Wholesale & retail | 2022 |
| Laila Irene Andersen AS | Professional & scientific | 2023 |
| Langaasen Holding AS | Wholesale & retail | 2023 |
| Langehaugen Va-Lag SA | Water & waste | 2025 |
| Langhus Stasjonskafé AS | Hospitality | 2026 |
| Langseter Consult AS | Real estate | 2005 |
| Langseter Eiendom AS | Real estate | 1988 |
| Langseter Holding AS | Real estate | 2015 |
| Langseth AS | | 2022 |
| Laps AS | Information & communication | 2017 |
| Lars Aas Snekkerverksted AS | Manufacturing | 2019 |
| Lars Døhl AS | Professional & scientific | 2022 |
| Lars Martin Borge AS | Health & social care | 2015 |
| Lars Trading AS | Wholesale & retail | 2013 |
| Laserhuset AS | Manufacturing | 2012 |
| Latindancenorway AS | Education | 2012 |
| Lazz Invest AS | Real estate | 2011 |
| Le Montmartre Ans | Hospitality | 1999 |
| Lederkompasset AS | Professional & scientific | 2025 |
| Leirvåg Holding AS | Information & communication | 2017 |
| Lelu Limon Pawel Lemieszek | Construction | 2006 |
| Lenoor AS | Wholesale & retail | 2026 |
| Leonardo Holding AS | Health & social care | 2018 |
| Lerskau Invest AS | Professional & scientific | 2020 |
| Lervold & Schau AS | | 2026 |
| Leziro AS | Wholesale & retail | 2026 |
| Lico AS | Health & social care | 2024 |
| Lightstone Holdings AS | Information & communication | 2021 |
| Like Home AS | Real estate | 2025 |
| Lindhardt Bygg AS | Construction | 2026 |
| Lindskog Maskin & Transport AS | Construction | 2026 |
| Lindtruppen AS | Households | 1958 |
| Linn Rammer Inn AS | Manufacturing | 2014 |
| Lizbiz AS | Wholesale & retail | 2020 |
| Ljosland Consulting AS | Information & communication | 2013 |
| Lloyd & Melón AS | Manufacturing | 2022 |
| Logehuset Ski AS | Hospitality | 2022 |
| Login AS | Information & communication | 2008 |
| Loke Invest AS | Financial services | 2005 |
| Lolaski AS | Hospitality | 2024 |
| Lomito AS | | 2026 |
| Longhurst Invest AS | Financial services | 2014 |
| Loraas Invest AS | Other services | 2021 |
| Lotmar Invest AS | Real estate | 2018 |
| Lowki AS | Information & communication | 2026 |
| LS Ventures AS | | 2024 |
| LTH Holding AS | | 2026 |
| Luminari AS | Information & communication | 2025 |
| Luna House AS | Hospitality | 2025 |
| Lunch Box AS | Hospitality | 2024 |
| Lunexa Group Nordics AS | Information & communication | 2025 |
| Lux Elektro AS | Construction | 2016 |