| Alex Egeland Invest AS | | 2022 |
| Alexander AS | Wholesale & retail | 2004 |
| Alexander Kristoff Limited Nuf | Arts & recreation | 2010 |
| Alexandria Algard Architects AS | Professional & scientific | 2012 |
| Alfa Beta Finans AS | Financial services | 2005 |
| Alfa Capital AS | Real estate | 2020 |
| Alfa Dekk Forus AS | Other services | 2019 |
| Alfa Energi AS | Construction | 2022 |
| Alfa Rør AS | Construction | 2004 |
| Alfa Sea AS | Professional & scientific | 2017 |
| Alfa-Bygg AS | Professional & scientific | 2011 |
| Alfe Invest AS | Professional & scientific | 2019 |
| Alfredo Garcia AS | Information & communication | 2017 |
| Algeco Nordics AS | Construction | 2020 |
| Algeco Norway AS | Construction | 2003 |
| Algoritme AS | Professional & scientific | 2024 |
| Alham Holding AS | | 2023 |
| Alico Stavanger AS | Other services | 2025 |
| Alina B. AS | Other services | 2023 |
| Aline AS | Professional & scientific | 2025 |
| Alks Holding AS | Financial services | 2013 |
| Alkymi AS | Financial services | 2006 |
| All Clean AS | Administrative & support | 2024 |
| All Or Nothing AS | | 2026 |
| ALL10 AS | Administrative & support | 2014 |
| ALL10 Elektro AS | | 2024 |
| ALL10 Entreprenør AS | Construction | 2019 |
| Alle Tjenester AS | Construction | 2019 |
| Alliance Invest AS | Real estate | 1988 |
| Alliance Invest Holding AS | Real estate | 2007 |
| Alliance Optikk Hillevåg AS | Wholesale & retail | 1996 |
| Allkontor AS | Wholesale & retail | 2017 |
| Allrep AS | Construction | 2005 |
| Allsupermoto AS | Wholesale & retail | 2015 |
| Allto Energy AS | Energy | 2023 |
| Allum & Verlo Ans | Hospitality | 1998 |
| Alma Opal AS | Real estate | 2012 |
| Almenningsgata 11 AS | Real estate | 2025 |
| Aloha Home AS | Construction | 2025 |
| Alopex AS | | 2005 |
| Alp Norge AS | Professional & scientific | 2010 |
| Alpha Wave Beverages AS | Manufacturing | 2020 |
| Alphabet AS | Real estate | 2008 |
| Alphafish AS | Professional & scientific | 2017 |
| Alstom Engineering and Services Limited | Manufacturing | 2010 |
| Alsultan AS | Wholesale & retail | 2022 |
| Altera Al Rayyan L.L.C. Nuf | Mining & quarrying | 2021 |
| Altera Infrastructure Crewing AS | Mining & quarrying | 2013 |
| Altera Infrastructure Group Ltd. Nuf | Administrative & support | 2022 |
| Altera Infrastructure Services AS | Professional & scientific | 2013 |
| Altera Infrastructure Ventures AS | Transport & logistics | 2021 |
| Altibox AS | | 2023 |
| Altien AS | Information & communication | 2024 |
| Altifiber Bidco AS | | 2024 |
| Altinex Industries AS | Professional & scientific | 2001 |
| Altiss Technologies AS | Professional & scientific | 2010 |
| Altus Intervention (Technologies) AS | Professional & scientific | 2015 |
| Altus Intervention AS | Mining & quarrying | 1980 |
| Altus Intervention Limited Nuf | Mining & quarrying | 2003 |
| Alurental AS | Administrative & support | 2023 |
| Alvastein AS | | 2022 |
| Alved AS | Professional & scientific | 2021 |
| Alveskjær Invest AS | Real estate | 2018 |
| Alveveien Utbyggingsselskap AS | Real estate | 2024 |
| Alvheim AS | Transport & logistics | 2005 |
| Am Heat Holding AS | | 1979 |
| Am Nutrition AS | Manufacturing | 2004 |
| Amanda Hagel AS | Other services | 2017 |
| Amara Studio AS | Wholesale & retail | 2024 |
| Amare Eiendom AS | Real estate | 1998 |
| Amatisi AS | | 2019 |
| Ambema Management AS | Professional & scientific | 2007 |
| Amberklinikken AS | Health & social care | 2009 |
| Ambiente Eiendom AS | Real estate | 2021 |
| Ambiente Racing AS | Arts & recreation | 2018 |
| Ambio AS | Professional & scientific | 2000 |
| Ambio People AS | Administrative & support | 2002 |
| Ambit AS | Information & communication | 2026 |
| Ambrosia Holding AS | Financial services | 2005 |
| Amdal Eiendom AS | Real estate | 2007 |
| Amden AS | Information & communication | 2015 |
| Ameliora AS | Professional & scientific | 2021 |
| Amero Holding AS | | 2026 |
| Amh Investering AS | Professional & scientific | 2023 |
| Amica Holding AS | Professional & scientific | 2013 |
| Amina Charging Holding AS | Manufacturing | 2026 |
| Amina Distribution AS | Wholesale & retail | 2021 |
| Amina International AS | Professional & scientific | 2022 |
| Amina Ipr AS | Administrative & support | 2021 |
| Aminet AS | Information & communication | 2023 |
| Amitec Holding AS | Information & communication | 2021 |
| Amka Restaurants AS | Hospitality | 2022 |
| Amles Invest AS | Real estate | 2005 |
| Ammelgoei AS | Wholesale & retail | 2023 |
| Amo Investering AS | Real estate | 2020 |
| Amorie AS | | 2022 |
| Ampel Da | Wholesale & retail | 2018 |
| Ampere Invest AS | Real estate | 2020 |
| Amplitude Ventures AS | Professional & scientific | 2021 |
| Ampliuz AS | Professional & scientific | 2020 |