| 05060 Taxi AS | Transport & logistics | 2024 |
| 100.XYZ AS | Information & communication | 2021 |
| 102 Asia Mat AS | Wholesale & retail | 2019 |
| 123ENKELT AS | Construction | 2026 |
| 1S Auto AS | | 2026 |
| 2 SA1X AS | Real estate | 2014 |
| 2KSOLUTION AS | Construction | 2023 |
| 2R Invest AS | | 2021 |
| 2R2K Holding AS | | 2026 |
| 3 ÈRN Trafikkskole AS | Education | 2006 |
| 4ADA AS | Professional & scientific | 2019 |
| 4B Bil AS | Wholesale & retail | 2021 |
| 4ESS AS | Information & communication | 2024 |
| 4PRINT AS | Professional & scientific | 2026 |
| 4U Hair Body Style AS | Other services | 1998 |
| 4UNITS AS | Administrative & support | 2024 |
| 5 Stars Services AS | Other services | 2024 |
| A & E Invest AS | | 2005 |
| A G Tømrertjenester AS | Construction | 2022 |
| A Rana Holdingselskap AS | | 2022 |
| A Team AS | Construction | 2018 |
| A-Consult AS | Professional & scientific | 2005 |
| A-One Catering Da | Hospitality | 2019 |
| A-Shoes Nuf | Wholesale & retail | 2019 |
| A-Å Grafisk Design & Reklame AS | Professional & scientific | 1986 |
| A. Husum Eiendom AS | Real estate | 2015 |
| A. Leinaas Holding AS | | 2021 |
| A. Neteland Holding AS | | 2024 |
| A.H Trafikkskole AS | Education | 2022 |
| A.W. Faber-Castell Vertrieb GmbH | Wholesale & retail | 2009 |
| A/S Danvikgaten 20 | Households | 1951 |
| A/S Katfos Fabrikker | | 1898 |
| A/S Konnerudgt. 12 | Households | 1955 |
| A/S Neumannsgate 16 | Households | 1951 |
| Aa Auto AS | Wholesale & retail | 2018 |
| Aa Eiendomsutvikling AS | Real estate | 2022 |
| Aa Executive Holding AS | Wholesale & retail | 2021 |
| Aabysgate 6 AS | Other services | 2015 |
| Aakvåg Fysioterapi AS | Health & social care | 2025 |
| Aakvåg Invest AS | Financial services | 1989 |
| Aandahl Invest AS | | 2023 |
| Aas Glass AS | Wholesale & retail | 2014 |
| Aase Broen Invest AS | | 2025 |
| Aasen Byggeledelse AS | Professional & scientific | 2016 |
| Aaserud Holding AS | Wholesale & retail | 2005 |
| Aass Bryggeri AS | Manufacturing | 2013 |
| Aass Konsulentfirma AS | Administrative & support | 2014 |
| AB Capital AS | Real estate | 2026 |
| AB Dentalservice AS | Manufacturing | 1996 |
| Abac Bygg AS | Construction | 2014 |
| Abbe Eiendom AS | Manufacturing | 2018 |
| Abc Dyreklinikk Drammen AS | Professional & scientific | 1999 |
| Abc-Rep Verksted Ans | | 1991 |
| Abdi Trans Nuf | Transport & logistics | 2021 |
| Abf Invest AS | Financial services | 2021 |
| Abg Consulting AS | | 2019 |
| Abg Payment Systems AS | Information & communication | 2018 |
| Abi Holding AS | | 2026 |
| Abicon Elektro AS | Construction | 1996 |
| Abicon Gruppen AS | Real estate | 2016 |
| Abrahamsen Software Solutions AS | Information & communication | 2011 |
| Absolute Wellness Ans | Wholesale & retail | 2007 |
| Aburayya Holding AS | | 2023 |
| Ac Cars Nordic AS | Wholesale & retail | 2014 |
| Ac Holding AS | Wholesale & retail | 2014 |
| Ac Juel AS | Professional & scientific | 1978 |
| Aca Holding AS | Real estate | 2007 |
| Acax Development AS | Information & communication | 2012 |
| Acd Eiendom Og Utleie AS | Manufacturing | 2024 |
| Ace Transport AS | Transport & logistics | 2022 |
| Acentio Norge AS | Information & communication | 1996 |
| Acergo AS | | 2022 |
| Acerlytics AS | Professional & scientific | 2021 |
| Acerlytics Consulting AS | Professional & scientific | 2022 |
| Acken AS | Financial services | 2017 |
| Acoinvest AS | Manufacturing | 2023 |
| Acorn Vannrens AS | Wholesale & retail | 2000 |
| Acr Invest AS | Real estate | 2012 |
| Acrh AS | | 2026 |
| Acro Invest AS | | 2013 |
| Activ Helse AS | Arts & recreation | 2020 |
| Active Pro AS | | 2014 |
| Ad Norwik AS | Construction | 2025 |
| Adan AS | Health & social care | 2021 |
| Adar AS | Other services | 2020 |
| Adda Byggkjemi AS | Manufacturing | 1993 |
| Addbrand Norway AS | Wholesale & retail | 1939 |
| Addovation AS | Professional & scientific | 2008 |
| Adelie Group AS | Wholesale & retail | 2020 |
| Aderian Group Norge AS | | 2025 |
| Adfahrer AB Nuf | Education | 2001 |
| Adgo Consult AS | Professional & scientific | 2026 |
| Aditus AS | Construction | 2019 |
| Admin & IT Consult AS | Education | 2014 |
| Ado Eiendom AS | Construction | 2013 |
| Ado Holding AS | | 2025 |
| Adoevents Ans | Arts & recreation | 2023 |
| Adrenalin Drammen AS | Arts & recreation | 2025 |
| Adrenalin Kristiansand AS | Arts & recreation | 2025 |
| Adrenalin No AS | Arts & recreation | 2025 |