| Abc Sushi AS | Hospitality | 2025 |
| Abc-Klinikken AS | Health & social care | 2006 |
| Abc-Klinikken Naprapatpraksis AS | Health & social care | 2006 |
| Abena Entreprenør AS | Professional & scientific | 2026 |
| Ability Group AS | | 2006 |
| Ability Media AS | Information & communication | 2022 |
| Abior AS | Wholesale & retail | 2022 |
| Ableon Medical AS | Professional & scientific | 2017 |
| Abn AS | | 2026 |
| Abonkentta AS | | 2022 |
| Abovo AS | Professional & scientific | 2011 |
| Abra Cards AS | Wholesale & retail | 2024 |
| Abs Formidling AS | Education | 2019 |
| Absolutt Data AS | Information & communication | 2024 |
| Absolutt Rens & Vask AS | Other services | 2014 |
| Ac/Dc Marine Consult AS | Construction | 2012 |
| Acapoco AS | | 2024 |
| Accel Ventures AS | | 2021 |
| ACCELER8. AS | Professional & scientific | 2014 |
| Accord Venture AS | | 2024 |
| Acerola AS | | 2022 |
| Achieve Eiendomsmegling AS | Real estate | 2020 |
| Achieve Holding AS | Real estate | 2022 |
| Acl 328 Holding AS | | 2023 |
| Aco Consult AS | Professional & scientific | 2012 |
| Aco Holding AS | Real estate | 2009 |
| Acon AS | Professional & scientific | 1995 |
| Acon Prosjekter AS | | 2007 |
| Acquire AS | Real estate | 2020 |
| Acriter Invest AS | Financial services | 2007 |
| Acsent.As AS | Construction | 2026 |
| Active Flow AS | Professional & scientific | 2020 |
| Activity AS | Information & communication | 2018 |
| Actor AS | Real estate | 1999 |
| Actual AS | Professional & scientific | 2024 |
| Ad Skulstad Invest AS | | 2026 |
| Adaptic Technology AS | Information & communication | 2021 |
| Adaris AS | Professional & scientific | 2000 |
| Adatech AS | Professional & scientific | 2022 |
| Additech AS | Professional & scientific | 2018 |
| Ade Afro Barbershope Ans | Other services | 2025 |
| Adept Concept AS | Information & communication | 2011 |
| Adepth Minerals AS | Professional & scientific | 2020 |
| Adeptor AS | Wholesale & retail | 2011 |
| Adfectus AS | Health & social care | 2021 |
| Adh Elementhus AS | Construction | 2020 |
| Adh Invest AS | Construction | 2019 |
| Adhama Holding AS | Administrative & support | 2004 |
| Adi Rådgivning AS | Information & communication | 2001 |
| Adil Transport AS | Transport & logistics | 2025 |
| Adlens AS | Information & communication | 2025 |
| Adlesi Fysioterapi AS | Health & social care | 2023 |
| Adlor AS | | 2019 |
| Administrasjonsbygget Solheimsviken AS | Real estate | 2007 |
| Admiral Hotel AS | Real estate | 2019 |
| Ado Arena Drift AS | Arts & recreation | 2013 |
| Ado AS | | 2020 |
| Adore AS | Wholesale & retail | 2014 |
| Adpt Invest AS | Real estate | 2012 |
| Adrenalin AS | Professional & scientific | 2000 |
| Advanced Asset Management AS | Real estate | 2005 |
| Advanced Innovations AS | Information & communication | 2016 |
| Advanced Mobile Computing and Technology AS | Wholesale & retail | 2002 |
| Advokat Birgitte G Eknes AS | Professional & scientific | 2020 |
| Advokat Clas Olsen AS | Professional & scientific | 2026 |
| Advokat David Hilton Holding AS | Financial services | 2005 |
| Advokat Jørgen Riple AS | Professional & scientific | 2013 |
| Advokat Kjetil Ottesen AS | Professional & scientific | 2022 |
| Advokat Ole-Petter G Hoff AS | Professional & scientific | 2005 |
| Advokat Solheim AS | Professional & scientific | 2018 |
| Advokat Svein Bergset Holding AS | Financial services | 2005 |
| Advokat Tungesvik AS | Professional & scientific | 2017 |
| Advokat Vegard Austgulen AS | Professional & scientific | 2014 |
| Advokat Vidar Broder Lund AS | Professional & scientific | 1989 |
| Advokatcompagniet Da | Professional & scientific | 1991 |
| Advokatconsult Nuf | Professional & scientific | 2015 |
| Advokatfirma Mæland & Co AS | Professional & scientific | 2014 |
| Advokatfirma Riisøen AS | Professional & scientific | 2004 |
| Advokatfirmaet Carl-Christian Grythe Hoff AS | Professional & scientific | 2008 |
| Advokatfirmaet Frølich, Fossmark & Tverborgvik AS | Professional & scientific | 2025 |
| Advokatfirmaet Gjesdahl AS | Professional & scientific | 2018 |
| Advokatfirmaet Holter AS | Professional & scientific | 2012 |
| Advokatfirmaet Jespersen AS | Professional & scientific | 2020 |
| Advokatfirmaet Judicium Da | Professional & scientific | 2000 |
| Advokatfirmaet Karlsson AS | Professional & scientific | 2021 |
| Advokatfirmaet Kyrre Ans | Professional & scientific | 2003 |
| Advokatfirmaet Landsvik & Larsen AS | Professional & scientific | 2020 |
| Advokatfirmaet Liabø & Øistensen AS | Professional & scientific | 1960 |
| Advokatfirmaet Nygaard AS | Professional & scientific | 2013 |
| Advokatfirmaet Oldermann AS | Professional & scientific | 2015 |
| Advokatfirmaet Rasmussen & Broch Da | Professional & scientific | 2019 |
| Advokatfirmaet Rastum AS | Professional & scientific | 2022 |
| Advokatfirmaet Riise & Brown AS | Professional & scientific | 2006 |
| Advokatfirmaet Soltvedt & Co Da | Professional & scientific | 2003 |
| Advokatfirmaet Støle AS | Professional & scientific | 2026 |
| Advokathuset Vest AS | Professional & scientific | 2018 |
| Advokatkontoret Fløien AS | Professional & scientific | 2017 |
| Ae Hus AS | Real estate | 2014 |
| Aegis Eiendom AS | Real estate | 2025 |
| Aegis Invest AS | | 2023 |