| 24-7 Ekspress AS | Transport & logistics | 2025 |
| 24/7 Ekspress AS | Transport & logistics | 1996 |
| 365EIENDOM AS | Real estate | 2020 |
| 3J Kreativ Studio Da | Professional & scientific | 2026 |
| 4M Holding AS | | 2022 |
| 6287 Holding AS | Construction | 2023 |
| 73BITS AS | Financial services | 2013 |
| A Hønsen Sjåførskole AS | Education | 1996 |
| A K Granheim AS | Construction | 1990 |
| A Til Å REGNSKAP1 AS | | 2024 |
| A-Partner AS | Education | 2020 |
| A. Hansen Invest AS | Arts & recreation | 2021 |
| A.G Tavleservice AS | Manufacturing | 2012 |
| Aa Pharma AS | | 2026 |
| Aasum Holding AS | Education | 2022 |
| Aban Tek AS | Professional & scientific | 2023 |
| Abed Transport AS | Transport & logistics | 2022 |
| Abhinav Jolly AS | | 2019 |
| Abiosa Pharma AS | Wholesale & retail | 2017 |
| Abk Tak AS | Construction | 1998 |
| Ac Klima AS | Construction | 2014 |
| Accessorius AS | Health & social care | 2023 |
| Acerinox Scandinavia AB | Manufacturing | 2015 |
| Ad Dekor AS | Professional & scientific | 1993 |
| Adrian Transport AS | Transport & logistics | 2023 |
| Agaton Sax AS | Other services | 2000 |
| Agea Holding AS | Professional & scientific | 2022 |
| Agenda Invest AS | | 2024 |
| Agilea AS | Professional & scientific | 2017 |
| Agilea Invest AS | Professional & scientific | 2021 |
| Ahn Renholdservice AS | Administrative & support | 2015 |
| Ahr AS | Professional & scientific | 2004 |
| Ajaib Invest AS | Hospitality | 2014 |
| Akershus Bygg- Og Vedlikehold AS | Construction | 2016 |
| Akershus Karosseri AS | Other services | 1989 |
| Akershus Maskinutleie AS | Administrative & support | 2022 |
| Akershus Og Østfold Virkestransport AS | Transport & logistics | 1988 |
| Akershus Reklame Team AS | Manufacturing | 1992 |
| Akinto Eiendom AS | Real estate | 2025 |
| Ako Kapital AS | | 2025 |
| Alab AS | Information & communication | 2012 |
| Alarmlink Oslo AS | Wholesale & retail | 2021 |
| Alexander Solberg Holding AS | Financial services | 2014 |
| Alfa Markiser AS | Wholesale & retail | 2018 |
| All About That Bass Tubakvartett Da | Arts & recreation | 2024 |
| Allrens AS | Other services | 2023 |
| Allèen Begravelsesbyrå AS | Other services | 2015 |
| Almera AS | | 2025 |
| Alpha Design AS | Construction | 2023 |
| Alpha Regnskap Ans | Professional & scientific | 2000 |
| Alpha Rør Service AS | Construction | 2025 |
| Alpin Invest AS | Real estate | 2025 |
| Alumeco Norge AS | Wholesale & retail | 1997 |
| Ametyst Velvære AS | Other services | 2026 |
| An Komfort Bygg AS | Construction | 2015 |
| Anasab AS | | 2024 |
| Andersenholding AS | | 2026 |
| Anker Renhold AS | Administrative & support | 2017 |
| Anv Gruppen AS | Construction | 2022 |
| Apropo Regnskap AS | Professional & scientific | 1975 |
| Arcol AS | Wholesale & retail | 1997 |
| Are Bredesen Holding AS | Health & social care | 2021 |
| Arild Strømhylden Holding AS | | 2021 |
| Armandito AS | Construction | 2025 |
| Arqdesign Norge AS | Wholesale & retail | 2019 |
| AS Heda Garasjeutstyr | Wholesale & retail | 1971 |
| AS Norfo | Wholesale & retail | 1963 |
| Asmin Engros AS | Wholesale & retail | 2024 |
| Assets Holding AS | Real estate | 2018 |
| Atech AS | Professional & scientific | 2012 |
| Atech Holding AS | Administrative & support | 2012 |
| Atech Security AS | Administrative & support | 2012 |
| Atv AS | Professional & scientific | 2004 |
| Audio Visuell AS | Arts & recreation | 2014 |
| Audioteknikk AS | Construction | 2012 |
| Aurstadfam AS | Transport & logistics | 2016 |
| Auto Care Skedsmo AS | Other services | 2026 |
| Auto Lounge AS | Wholesale & retail | 2016 |
| AUTO2 AS | Other services | 2013 |
| Automotive AS | Wholesale & retail | 2020 |
| Autoringen AS | Administrative & support | 2004 |
| Autoringen Digital AS | Wholesale & retail | 2022 |
| Autoringen Oslo AS | Wholesale & retail | 2022 |
| Autoshine Berger AS | Other services | 2020 |
| Avancia Sport Center Skedsmo AS | Arts & recreation | 2006 |
| Avra Holding AS | Transport & logistics | 1990 |
| Avra Utleie AS | Administrative & support | 2024 |
| Axo Prosjekt AS | | 2018 |
| Az Entreprenør AS | Construction | 2025 |
| Azam Rrotlla Malerteam AS | Construction | 2003 |
| Asle Skoveng Kranservice A/S | Construction | 1988 |
| B.O. Holding AS | | 2019 |
| Ba-Entreprenør AS | Construction | 2019 |
| Bagges AS | Wholesale & retail | 1999 |
| Bagges Eiendom AS | Wholesale & retail | 1912 |
| Bajasen AS | Wholesale & retail | 2023 |
| Bakerikonsulting AS | Manufacturing | 2022 |
| Bakåsveien 48 AS | Administrative & support | 2017 |
| BC Accounting AS | Professional & scientific | 2025 |
| Beau AS | Professional & scientific | 2021 |