| Audiocom AS | Wholesale & retail | 1987 |
| Audioped AS | Health & social care | 2024 |
| Auds Holding AS | Other services | 2002 |
| Auds Hudpleie Aquarama AS | Other services | 2023 |
| Auds Hudpleie Markens AS | Other services | 2016 |
| Audun Frustøl Elektro AS | Construction | 2021 |
| Augland Byggservice AS | Construction | 2013 |
| Augland Eiendom AS | Transport & logistics | 2015 |
| Augland Invest AS | | 2023 |
| Augland Sau Da | Agriculture & fishing | 2014 |
| Augland SVS AS | Education | 2014 |
| Augufine Drift AS | | 2015 |
| Aulin AS | Financial services | 2016 |
| Aune Consulting AS | Professional & scientific | 2026 |
| Aurebekk Elektro AS | Construction | 1989 |
| Aurebekk Montasje AS | Construction | 2011 |
| Aurebekk Sau Da | Agriculture & fishing | 2016 |
| Aurex AS | Information & communication | 2026 |
| Aurion AS | Health & social care | 2022 |
| Aurion Holding AS | Health & social care | 2022 |
| Aurora 1 AS | Administrative & support | 2023 |
| Aurora Galaxy AS | Transport & logistics | 2022 |
| Aurora Horizon AS | Transport & logistics | 2022 |
| Aurora Mosvold AS | Transport & logistics | 2021 |
| Aurora Offshore & Mooring Services AS | Administrative & support | 2021 |
| Aurora Offshore AS | Transport & logistics | 2021 |
| Aurora Offshore Crewing 2 AS | Administrative & support | 2026 |
| Aurora Offshore Management AS | Professional & scientific | 2022 |
| Aurora Partner AS | Education | 2023 |
| Aurora Shipholding AS | Administrative & support | 2021 |
| Aurora Shipping One AS | Transport & logistics | 2021 |
| Aurora Storm AS | Transport & logistics | 2022 |
| Aurum Økonomi AS | Professional & scientific | 2025 |
| Ausvig Invest AS | Financial services | 2004 |
| Ausviga Eiendom AS | Real estate | 2010 |
| Aut Maskinentreprenør Olav Martin Sørli AS | Construction | 1997 |
| Auto Agentur AS | Wholesale & retail | 2020 |
| Auto Marine Transport Inc Nuf | Transport & logistics | 2017 |
| Auto Teknikk AS | Wholesale & retail | 2010 |
| Auto Teknikk Bilforretning AS | Wholesale & retail | 1996 |
| Auto Teknikk Holding AS | Other services | 2000 |
| Auto-Key.No AS | Information & communication | 2022 |
| Autoflip AS | Wholesale & retail | 2023 |
| Autoform Kristiansand AS | Wholesale & retail | 2025 |
| Autofys AS | Health & social care | 2012 |
| Autoleie AS | Administrative & support | 1988 |
| Autoleie Eiendom AS | Other services | 2024 |
| Autoleie Eiendom Kristiansand AS | Real estate | 2022 |
| Autoleie Mobility AS | Administrative & support | 2010 |
| Autoleie Oslo AS | Administrative & support | 2008 |
| Autoleie Sørlandet AS | Administrative & support | 1976 |
| Autoleie Tromsø AS | Administrative & support | 2009 |
| Autosør AS | Wholesale & retail | 2026 |
| Autotek AS | Wholesale & retail | 2006 |
| Autotek Holding AS | Wholesale & retail | 2024 |
| Auver AS | | 2022 |
| Avelion AS | Information & communication | 2025 |
| Aveluna AS | Wholesale & retail | 2021 |
| Aventador Group AS | Transport & logistics | 2021 |
| Aventech AS | Professional & scientific | 2023 |
| Aventi AS | Real estate | 2005 |
| Avenyen 36 AS | Real estate | 2007 |
| Avenyen 7 AS | Real estate | 2011 |
| Avenyen Eiendom AS | Real estate | 2016 |
| Avenyen Handelsselskap AS | Professional & scientific | 2020 |
| Avenyen Invest AS | Real estate | 2020 |
| Avenyen Storhandel AS | Real estate | 2020 |
| Avfall Sør AS | Water & waste | 2003 |
| Avfall Sør Eiendom AS | Water & waste | 2010 |
| Avfall Sør Husholdning AS | Water & waste | 2010 |
| Avfall Sør Næring AS | Water & waste | 2018 |
| Avgiftspartner AS | Professional & scientific | 2003 |
| Avh Eiendom AS | Real estate | 2019 |
| Avitell AS | Construction | 1978 |
| Avnp Seksjon 10 AS | Real estate | 2022 |
| Avnp Seksjon 11 AS | Real estate | 2022 |
| Avnp Seksjon 12 AS | Real estate | 2022 |
| Avnp Seksjon 13 AS | Real estate | 2022 |
| Avnp Seksjon 14 AS | Real estate | 2022 |
| Avnp Seksjon 15 AS | Real estate | 2022 |
| Avnp Seksjon 18 AS | Real estate | 2022 |
| Avnp Seksjon 19 AS | Real estate | 2022 |
| Avnp Seksjon 2 AS | Real estate | 2022 |
| Avnp Seksjon 3 AS | Real estate | 2022 |
| Avnp Seksjon 4 AS | Real estate | 2022 |
| Avnp Seksjon 5 AS | Real estate | 2022 |
| Avnp Seksjon 8 AS | Real estate | 2022 |
| Avnp Seksjon 9 AS | Real estate | 2022 |
| Avrion Holding AS | | 2026 |
| Avtjern Holding AS | | 2023 |
| Avventura Holding AS | | 2025 |
| Awmn AS | Wholesale & retail | 2024 |
| Awv AS | Health & social care | 2021 |
| Axelo Eiendom AS | Real estate | 2026 |
| Axentra AS | Information & communication | 2025 |
| Axfam Holding AS | | 2023 |
| Axitec Entreprenør AS | Construction | 2024 |
| Axzera Holding AS | Information & communication | 2026 |
| Ayo Invest AS | | 2021 |
| Az Arkitektur AS | Professional & scientific | 2016 |