| Aursland Invest AS | | 2023 |
| Aursmoen Eiendom Ans | Real estate | 2003 |
| Aurtun Invest AS | Financial services | 2017 |
| Aurum AS | Information & communication | 2014 |
| Aurum Capital AS | | 2024 |
| Aurus AS | | 2024 |
| Aurvegen 11 AS | Real estate | 2019 |
| Aurvegen 13 AS | Real estate | 2017 |
| Aurvexi AS | Information & communication | 2025 |
| Auråen Holding AS | | 2024 |
| Aurélia Beauty AS | Other services | 2026 |
| Ausavi Nuf | Professional & scientific | 2010 |
| Ausen Industrier AS | Real estate | 2010 |
| Ausen Invest AS | | 2008 |
| Ausgezeichnet Invest AS | Wholesale & retail | 2023 |
| Austad AS | Real estate | 2012 |
| Austad Eiendomsutvikling AS | Real estate | 2010 |
| Austbø Helse AS | Health & social care | 2026 |
| Austeja Invest AS | | 2023 |
| Auster AS | Other services | 2004 |
| Auster Bryn AS | Other services | 2026 |
| Auster Salonger AS | Other services | 2005 |
| Auster Skøyen AS | Other services | 2025 |
| Auster Storo AS | Other services | 2020 |
| Austerlitz AS | | 2025 |
| Austgulen Capital AS | | 2020 |
| Austigard Arkitektur AS | Professional & scientific | 2013 |
| Austigard Design AS | Professional & scientific | 2020 |
| Austigard Holding | Real estate | 2015 |
| Austin Holding AS | | 2024 |
| Austin Lyngmyr & Co Advokatfirma AS | Professional & scientific | 2013 |
| Austintex AS | | 2019 |
| Austland AS | Real estate | 2020 |
| Austlid Eiendom AS | Real estate | 2018 |
| Austnes Invest AS | | 2024 |
| Australian Study Connection | Administrative & support | 2005 |
| Australian Transport Flytteservice AS | Transport & logistics | 2018 |
| Australiareiser AS | Administrative & support | 2005 |
| Austre Åsen AS | Professional & scientific | 2018 |
| Austrheim Holding AS | Real estate | 2016 |
| Austrian Airlines Norsk Avdeling Av Utenlandsk Foretak Nuf | Transport & logistics | 2000 |
| Austvest Halding AS | | 2026 |
| Austvold Consulting AS | Information & communication | 2012 |
| Austvær AS | Real estate | 1996 |
| Aut AS | Real estate | 2015 |
| Aut Rørleggermester Jan-Erik Østreng AS | Construction | 1989 |
| Autarkeia Capital AS | | 2018 |
| Autentish AS | Hospitality | 2023 |
| Authentic Europe AS | Administrative & support | 2018 |
| Authentic Me AS | Professional & scientific | 2024 |
| Authentic Scandinavia AS | Administrative & support | 2007 |
| Authenticore AS | Administrative & support | 2019 |
| Authera AS | Professional & scientific | 2022 |
| Authera Holding AS | Professional & scientific | 2022 |
| Authimate AS | Information & communication | 2025 |
| Authorized.No AS | Wholesale & retail | 2017 |
| Authén Arkitektur AS | Professional & scientific | 2026 |
| Auto Detailer AS | Other services | 2019 |
| Auto Detailing Da | Other services | 2023 |
| Auto Europe Deutschland GmbH | Information & communication | 2005 |
| Auto Invest AS | Wholesale & retail | 1985 |
| Auto Ital AS | Wholesale & retail | 2006 |
| Auto Ivanovski AS | Wholesale & retail | 2024 |
| Auto Joachim AS | Other services | 2014 |
| Auto Kso AS | Administrative & support | 2018 |
| Auto Marked AS | Wholesale & retail | 2023 |
| Auto Prime AS | Transport & logistics | 2017 |
| Auto Records Ans | Arts & recreation | 2007 |
| Auto Retail AS | Wholesale & retail | 2018 |
| Auto X AS | Wholesale & retail | 2022 |
| Auto-Boks-Service AS | Administrative & support | 1949 |
| Auto-Trio AS | Wholesale & retail | 1974 |
| Auto-Trio Holding AS | Real estate | 1985 |
| AUTO13 AS | Administrative & support | 1997 |
| Autobjørn A/S | Other services | 1968 |
| Autobjørn Bilutleie AS | Administrative & support | 2017 |
| Autocenteret Nordstrand AS | Wholesale & retail | 2005 |
| Autoco Industribygg AS | Other services | 1977 |
| Autocomplex 1 AS | Other services | 2023 |
| Autocomplex AS | Professional & scientific | 2019 |
| Autocore AS | Education | 2023 |
| Autocosmetic AS | Other services | 2001 |
| Autodesk Norway AS | Professional & scientific | 2019 |
| Autodesk Norway Operations AS | Information & communication | 2016 |
| Autodrift AS | Transport & logistics | 2007 |
| Autofix 1 AS | Other services | 2025 |
| Autogen AS | Manufacturing | 1977 |
| Autogruppen Norge AS | Wholesale & retail | 1999 |
| Autohjelp AS | Transport & logistics | 2018 |
| Autohub Oslo AS | Wholesale & retail | 2026 |
| Autoin Bilskade Alnabru AS | Other services | 2006 |
| Autoin Bilskade AS | Other services | 1988 |
| Autoklinikken Ital Bilservice AS | Other services | 2005 |
| AUTOLAGER51 SA | Transport & logistics | 2014 |
| Autolakkservice AS | Other services | 1997 |
| Autolease AS | Real estate | 2020 |
| Autolyze Vision AS | Information & communication | 2025 |
| Automagi Ltd Nuf | Information & communication | 2010 |
| Automaker Eiendom AS | Other services | 1987 |
| Automania Bilservice AS | Other services | 2017 |