| HÅNDVERKSPARTNER1 AS | Construction | 2025 |
| Høyer Strømmen AS | Wholesale & retail | 2012 |
| Ice Cream AS | Professional & scientific | 2017 |
| Iemi Invest AS | Financial services | 2011 |
| Ihs Norway Da | Arts & recreation | 2004 |
| Ikt Konsult Da | Administrative & support | 2002 |
| Importhuset Mat & Drikke AS | Wholesale & retail | 2026 |
| Inat Investing AS | Financial services | 2020 |
| Inglow AS | Other services | 2026 |
| Ingunn Eidsaunet AS | Financial services | 2017 |
| Inmatech AS | Wholesale & retail | 2018 |
| Inside Out AS | Wholesale & retail | 2016 |
| Inspo Bygg AS | Construction | 2024 |
| Intola Holding AS | Information & communication | 2022 |
| Intola Konsult AS | Information & communication | 2022 |
| Investlie AS | Wholesale & retail | 2021 |
| Investo Holdning AS | | 2023 |
| IP Bygg Service AS | Construction | 2019 |
| Iristel Norway AS | Information & communication | 2019 |
| Jafs Strømmen Da | Hospitality | 2026 |
| Jarle Martinsen Holding AS | Professional & scientific | 2021 |
| Jarrett Holding AS | | 2020 |
| Jasti Eiendom AS | Real estate | 2013 |
| JBD Finans AS | Professional & scientific | 2018 |
| JBS Holding AS | | 1989 |
| JK Barbershop Strømmen AS | Other services | 2025 |
| John Svendsen Invest AS | Real estate | 1991 |
| Jordbærpikene Strømmen AS | Hospitality | 2012 |
| JRB Invest AS | Real estate | 2016 |
| Js-Holding AS | Financial services | 2013 |
| JVT Invest AS | | 2025 |
| JVT Medical Services AS | Health & social care | 2025 |
| Jøssund Invest AS | Financial services | 2006 |
| K14 Invest AS | | 2026 |
| Kakehuset AS | Manufacturing | 2016 |
| Kalle Kapital AS | | 2005 |
| Kamel Eiendom AS | Real estate | 2022 |
| Kamel Holding AS | Real estate | 2013 |
| Kantine Mat & Services AS | Hospitality | 2022 |
| Karl M Gulbrandsen Stansefabrikk AS | Manufacturing | 2006 |
| Karrieresupport AS | Education | 2020 |
| Kaso AS | Professional & scientific | 2005 |
| Katrine Solbakke AS | | 2018 |
| Kenneth Danielsen Holding AS | Administrative & support | 2024 |
| Kinsarvik Naturkost Strømmen AS | Wholesale & retail | 2025 |
| Kirkerød Engineering AS | Professional & scientific | 2024 |
| KJ Entreprenør AS | Construction | 2025 |
| Kjelling Eiendom AS | | 2025 |
| Kjøkken Og Varme AS | Construction | 1970 |
| Kjøttbasaren Strømmen AS | Wholesale & retail | 2021 |
| KMG Byggservice AS | Administrative & support | 2016 |
| KMG Eiendom AS | Real estate | 2010 |
| KMG Invest II AS | | 2025 |
| KMG Maskin AS | Administrative & support | 2004 |
| Knutsen Invest AS | | 2023 |
| Kodekru AS | Information & communication | 2026 |
| Kong Holding AS | | 2026 |
| Konserva AS | Construction | 2026 |
| Kosmodrome Games AS | Information & communication | 2026 |
| KP Bygg AS | Construction | 2019 |
| Krabe Consulting AS | | 2024 |
| KT Global Invest AS | Real estate | 2013 |
| Ktmh Invest AS | Real estate | 2023 |
| Kuben Lekeplass AS | Arts & recreation | 2025 |
| Kurt Odin AS | Wholesale & retail | 2022 |
| Kvalitet Entreprenør AS | Construction | 2022 |
| KVT Holding AS | | 2023 |
| L.C.T. Holding AS | | 2025 |
| La Bonita Frisør Og Hudpleie AS | Other services | 2010 |
| Laaver AS | | 2021 |
| Lam Holding AS | | 2020 |
| Lapasta AS | Hospitality | 2025 |
| Laraib Holding AS | | 2025 |
| Laserakademiet AS | Education | 2021 |
| Latif Hajrizi AS | Wholesale & retail | 2016 |
| Lcama AS | Manufacturing | 2024 |
| Le'Ganz Strømmen AS | Wholesale & retail | 2012 |
| Leading Edge AS | Education | 2009 |
| Learnalist AS | Information & communication | 2026 |
| Ledonline AS | Wholesale & retail | 2012 |
| Legit VDC AS | Information & communication | 2024 |
| Lekeparken AS | Health & social care | 2022 |
| Leon Notkevich Invest AS | | 2019 |
| Lephan AS | Wholesale & retail | 2018 |
| Lephan Invest AS | Hospitality | 2022 |
| Levero AS | Transport & logistics | 2025 |
| LIEN42 Invest AS | | 2023 |
| Lille Pho Holding AS | Hospitality | 2024 |
| Lillestrøm Bil & Karosseri AS | Other services | 1986 |
| Litlehornet AS | | 2018 |
| Liv AS | Education | 2015 |
| Livaro AS | Real estate | 2025 |
| Lookprof AS | Wholesale & retail | 2017 |
| Lovelo AS | Information & communication | 2013 |
| LS Totalentreprenør AS | Real estate | 2026 |
| Luksus Bad for Alle AS | Construction | 2022 |
| Lux Investment Group AS | Real estate | 2023 |
| Lyngsaas Eiendom AS | Real estate | 2026 |
| Lørenskog Matkonsept AS | Hospitality | 2025 |
| M&S Import AS | Wholesale & retail | 2020 |