| 0FRI10 AS | Real estate | 2021 |
| 0FRI101 AS | | 2026 |
| 1 Skritt Foran AS | Education | 2014 |
| 4 You Barbershop AS | Other services | 2025 |
| 88 Eiendom AS | Real estate | 2008 |
| 88 Holding AS | Real estate | 2005 |
| 88 Invest AS | Real estate | 2005 |
| A&K Holding AS | Administrative & support | 2020 |
| A. Abelsen Holding AS | | 2025 |
| A. Martinsen Eiendom AS | Real estate | 2012 |
| A. Martinsen Invest AS | Arts & recreation | 2005 |
| A. Varreng Tannklinikk AS | Health & social care | 2025 |
| A.H. Klemsdal AS | | 2013 |
| A.T.M Invest AS | Real estate | 2012 |
| Aa Capital AS | Real estate | 2023 |
| Aakre Investments AS | | 2022 |
| Aarvik Holding AS | | 2021 |
| Aas Management & Consulting AS | Professional & scientific | 2025 |
| Aat Drift AS | Wholesale & retail | 2025 |
| Ab-Utvikling AS | Real estate | 2005 |
| Abakus Regnskap & Rådgivning AS | Professional & scientific | 2022 |
| Abc Miljø AS | Wholesale & retail | 2021 |
| Abr Partners AS | | 2019 |
| Abraham Holding AS | | 2026 |
| Acb Invest AS | Real estate | 2012 |
| Accend AS | Professional & scientific | 2024 |
| Acoa AS | Professional & scientific | 2022 |
| Acoa Regnskap AS | Professional & scientific | 2026 |
| Activ Eiendom AS | Real estate | 2005 |
| Active Trening AS | Arts & recreation | 2011 |
| Ad Utvikling AS | Real estate | 2019 |
| Adal Holding AS | Real estate | 2019 |
| Adas Skomakeri AS | Other services | 2013 |
| Addifolia AS | Information & communication | 2026 |
| Adm AS | | 1988 |
| Advokat Hilde Jæger AS | Professional & scientific | 2019 |
| Advokat K Jakobsen AS | Professional & scientific | 2024 |
| Advokatfirmaet Berggren AS | Professional & scientific | 2017 |
| Advokatfirmaet Bjørnebekk Og Martinsen AS | Professional & scientific | 2014 |
| Advokatfirmaet Dennis R Brorstrøm AS | Professional & scientific | 1994 |
| Advokatfirmaet Hohmann AS | Professional & scientific | 2018 |
| Advokatfirmaet Lex AS | Professional & scientific | 2010 |
| Advokatfirmaet Planke Da | Professional & scientific | 2005 |
| Afpt Global AS | Professional & scientific | 2025 |
| Afro Africa Shop AS | Wholesale & retail | 2019 |
| Agenda Regnskap AS | Professional & scientific | 2011 |
| Agroinvest AS | Real estate | 2015 |
| Ahhelse AS | Health & social care | 2021 |
| Aim Economics AS | Health & social care | 2023 |
| Airel AS | | 2023 |
| Ak-Holding AS | Real estate | 2008 |
| Akademiet for Personlig Trening AS | Health & social care | 2010 |
| Aker Hjortaas Dialog AS | Professional & scientific | 2006 |
| Akg Holding AS | | 2026 |
| Aktiv Fredrikstad AS | Real estate | 2012 |
| Al Capone AS | Administrative & support | 2008 |
| Alarm 24 Sikkerhet AS | Construction | 2016 |
| Alborilla AS | Real estate | 2006 |
| Aldata Solution AB | | 2004 |
| Aleksander Holding AS | Financial services | 2012 |
| Alexander Ferner Holdning AS | Financial services | 2005 |
| Alexander Moog | Construction | 2006 |
| Alingi AS | Administrative & support | 2025 |
| Alkibiades Invest AS | Other services | 2002 |
| All in AS | Real estate | 2009 |
| Allday AS | Real estate | 2005 |
| Allrent AS | Real estate | 1999 |
| Alm Invest AS | Real estate | 1997 |
| Almas Bygg AS | | 2025 |
| Alnour AS | Hospitality | 2025 |
| Alt I Eiendom AS | Real estate | 2017 |
| Altezza Safety AS | | 2019 |
| Alvimveien 59 AS | Real estate | 2023 |
| Alwa Eiendom AS | Real estate | 2020 |
| Always Content AS | Arts & recreation | 2023 |
| Alya Og Salam Services | Professional & scientific | 2003 |
| Ambjørnrød Eiendom AS | Real estate | 2020 |
| Ambjørnrød Gård AS | Real estate | 2022 |
| Amedia Annonse Follo Og Østfold AS | Professional & scientific | 2022 |
| Ampera AS | Construction | 2025 |
| Anco Invest AS | Wholesale & retail | 2019 |
| Andek Holding AS | | 2021 |
| Andersen Eiendom Fredrikstad AS | Real estate | 2016 |
| Andersen Holding AS | Real estate | 1998 |
| Andreas Munch AS | | 2021 |
| Andreas Pedersen Holding AS | | 2022 |
| Andreas Sørlie AS | | 2012 |
| Andresen Forvaltning AS | Real estate | 1975 |
| Andy Pett AS | Arts & recreation | 2019 |
| Angelheart Invest AS | | 2012 |
| Anker Hansen Eiendom AS | Real estate | 2025 |
| Anker Hansen Industrier AS | Real estate | 2007 |
| Ann Margret Apold-Aasen AS | Health & social care | 2005 |
| Ann-Kristin Ryen Holding AS | Financial services | 2008 |
| Annas Tannklinikk AS | Health & social care | 2018 |
| Anonsen Invest AS | Real estate | 2006 |
| ANS HEFELS Marit Hefel og Torleif Møgster | Wholesale & retail | 1988 |
| App Businesspartner AS | Information & communication | 2016 |
| Appixos AS | Information & communication | 2025 |
| Arb AS | Agriculture & fishing | 2019 |