| Levende Boliger AS | Real estate | 2016 |
| Liberi Eiendom AS | Real estate | 2023 |
| Liberty Management AS | Professional & scientific | 2026 |
| Lier Anlegg AS | Construction | 2004 |
| Lier Asvo Holding AS | Health & social care | 1996 |
| Lier Asvo Kommuneleveranser AS | Health & social care | 2024 |
| Lier Asvo Vta/Aft AS | Health & social care | 2024 |
| Lier Bil-Demontering Ans | Wholesale & retail | 2003 |
| Lier Bilgjenvinning AS | Wholesale & retail | 2006 |
| Lier Boliginvest AS | Real estate | 2020 |
| Lier Boligselskap AS | Real estate | 1999 |
| Lier Boligutleie AS | Real estate | 2017 |
| Lier Dyreklinikk AS | Professional & scientific | 2012 |
| Lier Eiendom AS | Real estate | 2017 |
| Lier Everk Holding AS | Energy | 1998 |
| Lier Forberging Da | Agriculture & fishing | 1999 |
| Lier Frukt Og Grønt AS | Wholesale & retail | 2002 |
| Lier Fruktlager AS | Real estate | 2010 |
| Lier Gardsdrift Da | Real estate | 2014 |
| Lier Gartnerier AS | Real estate | 2015 |
| Lier Golfsimulator AS | Real estate | 2026 |
| Lier Grafiske AS | Manufacturing | 1988 |
| Lier Graving Og Transport AS | Construction | 2013 |
| Lier Grønt AS | Agriculture & fishing | 1997 |
| Lier Hud Og Fot Da | Other services | 2004 |
| Lier Naprapatklinikk AS | Health & social care | 2010 |
| Lier Natur Og Landbruks Barnehage SA | Education | 2002 |
| Lier Paintball AS | Arts & recreation | 2024 |
| Lier Pizza AS | Hospitality | 2016 |
| Lier Plast AS | Manufacturing | 1999 |
| Lier Regnskap AS | Professional & scientific | 1995 |
| Lier Regnskap Holding AS | | 2026 |
| Lier Vekst AS | Real estate | 2001 |
| Lierbakkene AS | Real estate | 2018 |
| Lierboden AS | Real estate | 2025 |
| Lierbyen Legesenter AS | Health & social care | 2023 |
| Lierbyen Optikk AS | Wholesale & retail | 2007 |
| Lierbyen Videosenter Da | Administrative & support | 2008 |
| Lierbær AS | Agriculture & fishing | 2023 |
| Lierelva Grunneierlag SA | Real estate | 1948 |
| Lierelven Jordvanning SA | Agriculture & fishing | 1976 |
| Lierkalv Da | Manufacturing | 2006 |
| Lierposten AS | Information & communication | 1995 |
| Lierterapeutene Da | Health & social care | 2023 |
| Lifescience Bridge Consulting AS | Professional & scientific | 2021 |
| Lifting & Safety International AS | Information & communication | 1995 |
| Liljenroth & Norstad AS | Health & social care | 1927 |
| Lille Stasjon AS | Wholesale & retail | 2020 |
| Lillepew Tjenester Nuf | Health & social care | 2021 |
| Lillesnekkeri AS | Manufacturing | 2019 |
| Line Varskog Gestaltterapi AS | Health & social care | 2021 |
| Linnes Panorama AS | Real estate | 2019 |
| Linnic Invest AS | Financial services | 2021 |
| Lisether AS | Wholesale & retail | 2015 |
| Litus AS | Professional & scientific | 1989 |
| Lorbivma AS | Real estate | 2021 |
| Lotech AS | Professional & scientific | 2007 |
| Ludvigsen Opsal Backe & Gravningsbråten Investering Da | | 1999 |
| Lund Bilsenter AS | Wholesale & retail | 2021 |
| Lundby Holding AS | Financial services | 2016 |
| Lunestad Holding AS | | 2019 |
| Luol Invest AS | | 2021 |
| Lux Milewska AS | Administrative & support | 2026 |
| Luxera AS | Construction | 2014 |
| Lyfjell Eiendom AS | Real estate | 1996 |
| Lynvingen Invest AS | | 2021 |
| M.Andresen Holding AS | | 2016 |
| Maeser AS | Financial services | 2012 |
| Magron AS | | 2005 |
| Malik Ali AS | Transport & logistics | 2025 |
| Malimi AS | Wholesale & retail | 2021 |
| Mama Bygg 1 AS | Construction | 2013 |
| Mama Bygg AS | Construction | 2015 |
| Mama Dom Invest AS | Construction | 2019 |
| Maridalsveien 91 Eiendom AS | Real estate | 2011 |
| Marvince Holding AS | | 2024 |
| MASKINENTREPRENØR1 AS | Wholesale & retail | 2021 |
| Maskintakst AS | Professional & scientific | 2017 |
| Matilde Solbakken AS | Arts & recreation | 2024 |
| Matuva Holding AS | | 2021 |
| Mazet Invest AS | | 2019 |
| MDK Helse AS | Health & social care | 2020 |
| Mehak Pizza Restaurant AS | Hospitality | 2013 |
| Mehren Eiendom AS | Real estate | 2015 |
| Meierikvartalet AS | Real estate | 1989 |
| Merikroken Barnehage SA | Education | 1978 |
| Meuble AS | Wholesale & retail | 2022 |
| Migla AS | | 2020 |
| Millennium Holding AS | Professional & scientific | 2015 |
| Min Advokat AS | Professional & scientific | 2022 |
| Mineral Holding AS | Mining & quarrying | 2011 |
| Mir Eiendom AS | Professional & scientific | 2022 |
| Mjøsund & Co AS | Information & communication | 1983 |
| MKS Service AS | Administrative & support | 2019 |
| MLB AS | Financial services | 2012 |
| MMP Consulting AS | Information & communication | 2009 |
| Modul-System AS | Wholesale & retail | 2013 |
| Moelsa Industrier AS | Manufacturing | 1990 |
| Moju Invest AS | Real estate | 2022 |
| Monolupa Holding AS | Financial services | 2018 |