| Akoa AS | | 1986 |
| Akros AS | | 2025 |
| Akros Invest AS | Information & communication | 2023 |
| Akros Regnskap Og Forvaltning AS | Professional & scientific | 2025 |
| Aksa Invest AS | | 2024 |
| Akse AS | Professional & scientific | 2008 |
| Akt Eiendom Sør AS | Real estate | 2026 |
| Akt Haddeland AS | | 2026 |
| Akt Solution AS | | 2026 |
| Aktiv Gruppen Bergen AS | Real estate | 2008 |
| Aktiv Lillesand AS | Real estate | 2026 |
| Aktiv Service & Montasje AS | Administrative & support | 2016 |
| Aktiva Consulting AS | Professional & scientific | 2005 |
| Akulight AS | Manufacturing | 2016 |
| Al Dikar Transport AS | Transport & logistics | 2020 |
| Al Holdning AS | | 2026 |
| Al Lømslandsvei 25 AS | Real estate | 2018 |
| Ala Arkitekter AS | Professional & scientific | 2005 |
| Aladdin Drift SA | Real estate | 2013 |
| Albanian Wine AS | Wholesale & retail | 2025 |
| Albert Bjercke Holding AS | | 2025 |
| Albert Eiendom AS | Real estate | 2014 |
| Albert Investment AS | Real estate | 2002 |
| Albertine Frisør AS | Other services | 2018 |
| Aleksina AS | Information & communication | 2002 |
| Aleppo AS | Wholesale & retail | 2020 |
| Alex Bilmester AS | Other services | 2017 |
| Alfa Drift AS | Administrative & support | 2015 |
| Alfa Lagerhotell AS | Transport & logistics | 2008 |
| Alfa Radon Norge AS | Wholesale & retail | 2010 |
| Algotrade AS | Information & communication | 2019 |
| Alhoot AS | Hospitality | 2021 |
| Alibaba Restaurant AS | Hospitality | 2018 |
| Alibi Fredrikstad AS | Hospitality | 2019 |
| Alinea AS | Professional & scientific | 2010 |
| Alipharma Holding AS | Wholesale & retail | 2025 |
| Aliva AS | Manufacturing | 2020 |
| All Inn AS | Hospitality | 2025 |
| Allfather AS | Arts & recreation | 2023 |
| Allgrid AS | Manufacturing | 2015 |
| Alliance Optikk Borning AS | Wholesale & retail | 2008 |
| Allmy.Energy AS | Information & communication | 2022 |
| Allova AS | Professional & scientific | 2014 |
| Alma Eik AS | Professional & scientific | 2012 |
| Almo Invest AS | Financial services | 2005 |
| Alnor Service AS | Construction | 2022 |
| Alp Elektro AS | Professional & scientific | 2019 |
| Alpaca Norge AS | Wholesale & retail | 2018 |
| Alpha Hodl AS | | 2025 |
| Alpha-Holding AS | Real estate | 2018 |
| Alphah AS | Professional & scientific | 2023 |
| Alphaone AS | Information & communication | 2020 |
| Alphaville AS | Real estate | 1992 |
| Alphaville Holding AS | Information & communication | 2008 |
| Alphaville Productions AS | Information & communication | 2008 |
| Alquds AS | Wholesale & retail | 2023 |
| Alt Er Mulig AS | Education | 2018 |
| Alt I Høyde AS | Administrative & support | 2023 |
| Altadena AS | | 2020 |
| Alternus AS | Real estate | 1997 |
| Altiskog AS | Agriculture & fishing | 2019 |
| Altitudo AS | Real estate | 2018 |
| Alu Design & Services AS | Professional & scientific | 2023 |
| Alu Stigen AS | Manufacturing | 1994 |
| Alustrax AS | Manufacturing | 2004 |
| Alustrax Group AS | | 2025 |
| Alutions AS | | 2026 |
| Alutions Distribution AS | Wholesale & retail | 2004 |
| Alutions Innovation AS | | 2026 |
| Amalienborg Aveny AS | Real estate | 2011 |
| Amalienborg Brygge 2 AS | Real estate | 2022 |
| Amalienborg Brygge 3 AS | Real estate | 2022 |
| Amalienborg Brygge 4 AS | Real estate | 2025 |
| Amalienborg Brygge AS | Real estate | 2016 |
| Amalienborg Brygge Utbygging AS | Real estate | 2021 |
| Amalienborg Lumberveien 13 AS | Real estate | 2013 |
| Amano Holding AS | Professional & scientific | 2007 |
| Amarone Invest AS | Wholesale & retail | 2005 |
| Amazing Grapes AS | Education | 2012 |
| Amba Investments AS | | 2015 |
| Ambisjon Pluss Da | Education | 2020 |
| Ambrina AS | Real estate | 2016 |
| Ambu Norge Filial Nuf | Wholesale & retail | 2015 |
| Ambus AS | Professional & scientific | 2008 |
| Amelsberg AS | Professional & scientific | 2024 |
| Amer Eiendom AS | Real estate | 2012 |
| Ameta AS | Professional & scientific | 2012 |
| Ameta Ignite AS | Information & communication | 2022 |
| Amicas AS | Wholesale & retail | 2022 |
| Amj Holding AS | Construction | 2007 |
| Amjf Holding AS | Wholesale & retail | 2019 |
| Ammonia AS | Professional & scientific | 2019 |
| Amo Agnieszka Otto | Construction | 2008 |
| Amo Eiendom AS | Real estate | 2024 |
| Ampersand AS | Professional & scientific | 2023 |
| Ampersand Holding AS | | 2023 |
| Amsea AS | Real estate | 2018 |
| Amtedal & Hansen Arkitektkontor AS | Professional & scientific | 2000 |
| Amundlien Holding AS | Financial services | 2011 |
| Amundsen Radiology AS | Health & social care | 2021 |