| 1-VENN AS | Hospitality | 2016 |
| 123 Sushi AS | Hospitality | 2021 |
| 12HUS Invest | | 2023 |
| 2 Nordic Group AS | | 2026 |
| 2CE Nail Beauty AS | Other services | 2024 |
| 2TEM AS | Financial services | 2015 |
| 3P Distribusjon AS | Wholesale & retail | 1997 |
| A Team Management AS | Professional & scientific | 2013 |
| A&B Scandinavia AS | Professional & scientific | 2006 |
| A&E Luxury AS | Other services | 2020 |
| A-Skills AS | | 2025 |
| A.K. Kvalitet Entreprenør AS | Construction | 2020 |
| Aag Entreprenør AS | Construction | 2023 |
| Aandalen Holding AS | Financial services | 2016 |
| AB Klipp Triaden AS | Other services | 1982 |
| Aba-Skol AS | Transport & logistics | 2007 |
| Abc Kitchen AS | Hospitality | 2026 |
| Abdex Transport AS | Transport & logistics | 2022 |
| Abm Entreprenør AS | Construction | 2021 |
| Abmas Elektro AS | Construction | 2025 |
| Absolute Day AS | Other services | 2023 |
| Abtf AS | Hospitality | 2023 |
| Academica Malerentreprenøren AS | Construction | 2006 |
| Acamar Capital AS | | 2023 |
| Active Transport Service AS | Transport & logistics | 2012 |
| Activehost AS | | 2005 |
| Adam Diagnostics AS | Health & social care | 2017 |
| Adams Auto AS | Wholesale & retail | 2020 |
| Addo Logistikk AS | Transport & logistics | 2018 |
| Ademi AS | Transport & logistics | 2024 |
| Adjuvo Eiendom AS | Real estate | 1999 |
| Advanced Power Technologies Ans | Wholesale & retail | 1993 |
| Advitec AS | Professional & scientific | 2025 |
| Advokatfirmaet Sander AS | Professional & scientific | 2016 |
| Advsan Holding AS | Professional & scientific | 2016 |
| Aeon AS | Information & communication | 2017 |
| Afg Pensjon AS | Financial services | 2011 |
| Afm Holding AS | Construction | 2025 |
| Agenturhuset Salg AS | Wholesale & retail | 1989 |
| Agenturhuset Utleie AS | Administrative & support | 1996 |
| Agh AS | Financial services | 2005 |
| Agvik AS | Construction | 2013 |
| Aha Holding AS | | 2026 |
| AI89 Holding AS | | 2021 |
| Aim Invest AS | Information & communication | 2018 |
| Ak Aastad Holding AS | | 2024 |
| Akershus Bilutleie AS | Administrative & support | 2025 |
| Akershus Car Senter AS | Wholesale & retail | 2021 |
| Akershus Legesenter AS | Health & social care | 2018 |
| Aktiv Personlig Trening AS | Education | 2005 |
| Aktiv Rørinspeksjon AS | Water & waste | 2000 |
| Akupunkturhuset AS | Health & social care | 1998 |
| Alanya Marked AS | Wholesale & retail | 2025 |
| Albicore AS | Information & communication | 2012 |
| Algol Consulting AS | Professional & scientific | 1989 |
| Alingar Invest AS | Transport & logistics | 2024 |
| All-Trade Norge Da | Wholesale & retail | 1990 |
| Allergan Sales Ltd | Wholesale & retail | 1999 |
| Allergan Trading International Ltd | Wholesale & retail | 1999 |
| Alliedsignal Aftermarket Europe | | 1995 |
| Allkopi Holding AS | Manufacturing | 2007 |
| Alltak AS | Construction | 2015 |
| Alltid Rent-Kantine Og Renhold AS | Hospitality | 2006 |
| Alpegro AS | Wholesale & retail | 2021 |
| Alpha Team AS | Construction | 2021 |
| Alt I Installasjon AS | Construction | 2014 |
| Alt Innen VVS AS | Construction | 2020 |
| Altegruppen AS | Information & communication | 2017 |
| Am Service AS | Real estate | 2005 |
| Amaan Holding AS | Real estate | 2023 |
| Amer Sports Norge AS | Wholesale & retail | 1981 |
| Ametso Holding AS | Education | 2022 |
| Anceka AS | Wholesale & retail | 2014 |
| Andhau AS | | 2022 |
| Andreas K.M. AS | Manufacturing | 2006 |
| Ansi Eiendom AS | Real estate | 2019 |
| Anyu Klinikken AS | Health & social care | 2014 |
| Ap Insight AS | Information & communication | 2025 |
| Apeks AS | Wholesale & retail | 2022 |
| Apex S&N AS | Wholesale & retail | 2025 |
| Apila AS | Construction | 2021 |
| Apila Gruppen AS | Construction | 2024 |
| Apotek 1 Gruppen AS | Wholesale & retail | 2001 |
| Apotek Oslo Bussterminal AS | Wholesale & retail | 2025 |
| Aquamedic AS | Professional & scientific | 2011 |
| Aquilos AS | Wholesale & retail | 2016 |
| Arash AS | Health & social care | 2015 |
| Aray AS | Health & social care | 2023 |
| Archaeological Research AS | Information & communication | 2014 |
| Arctic B&C Norway AS | Construction | 2018 |
| Arctic Dreams Norway AS | Administrative & support | 2019 |
| Ardeo AS | Professional & scientific | 2018 |
| Ardvale AS | | 2025 |
| Aren Invest AS | Wholesale & retail | 2024 |
| Arifs Transport AS | Transport & logistics | 2022 |
| Arnheim Investment & Pension Consulting AS | Real estate | 1995 |
| Aroma AS | Education | 2011 |
| Artis Global AS | Wholesale & retail | 2020 |
| Arun AS | Education | 2018 |
| AS Elektro-Montering | Construction | 1972 |