| A Board AS | Professional & scientific | 2020 |
| A Bright Future AS | | 2021 |
| A Bygg Entreprenør AS | Construction | 2005 |
| A Bygg Gruppen AS | Real estate | 1987 |
| A C Hvoslef AS | Health & social care | 2007 |
| A C Smith & Co AS | Manufacturing | 1998 |
| A C Smith Eiendom AS | Real estate | 1950 |
| A Capital AS | Professional & scientific | 2021 |
| A Casa Tua Ans | Hospitality | 2000 |
| A Day's March Shirts & Staples Norway AS | Wholesale & retail | 2023 |
| A Elektro AS | Construction | 2025 |
| A Group AS | | 2005 |
| A H Agency Ans | | 1989 |
| A Hillestad AS | Professional & scientific | 1975 |
| A Hvide Holding AS | Real estate | 2005 |
| A Invest Oslo AS | | 2024 |
| A Johannesen Holdings AS | | 2023 |
| A La Carte Produkter AS | Wholesale & retail | 1998 |
| A Langfeldt Consult AS | Professional & scientific | 2025 |
| A Little Good Agency AS | Professional & scientific | 2024 |
| A Little Good Holding Company AS | | 2025 |
| A M Frisør AS | Other services | 2023 |
| A M King Industries Inc | Wholesale & retail | 2006 |
| A Madsstuen AS | Real estate | 1927 |
| A New Type of Infinity AS | Financial services | 2013 |
| A New Type of Investment AS | Professional & scientific | 2013 |
| A P Mustad Hold AS | Real estate | 2007 |
| A People AS | Information & communication | 2024 |
| A Pluss AS | Professional & scientific | 2009 |
| A Rapp Invest AS | | 2021 |
| A Riseth Invest AS | Professional & scientific | 2020 |
| A Small Production AS | Information & communication | 2026 |
| A Songcove Holding AS | | 2021 |
| A Sæther Compagniet AS | Real estate | 1982 |
| A T Blomster & Interiør Da | Wholesale & retail | 1989 |
| A T Kearney AS | Professional & scientific | 1989 |
| A T Olssons Byggservice AB | Construction | 1995 |
| A Til B Trafikkskole AS | Education | 2025 |
| A Til Å Tjenester AS | Professional & scientific | 2022 |
| A Til Å Transport AS | Transport & logistics | 2019 |
| A Worker | Administrative & support | 2013 |
| A&A Marketing AS | Professional & scientific | 2025 |
| A&A Star Productions AS | Arts & recreation | 2014 |
| A&B Export AS | Wholesale & retail | 2020 |
| A&C Holding AS | Real estate | 2021 |
| A&E Eiendomsutvikling AS | Real estate | 2007 |
| A&E Holding AS | | 2024 |
| A&F Elektro AS | Professional & scientific | 2020 |
| A&G Transport AS | Transport & logistics | 2021 |
| A&H Capital AS | | 2024 |
| A&J Invest AS | | 2025 |
| A&J Publishing Da | Information & communication | 2025 |
| A&L Holding AS | | 2023 |
| A&M Beauty Point AS | Other services | 2025 |
| A&M Holdings AS | Financial services | 2015 |
| A&O Holding AS | | 2022 |
| A&S Partners AS | | 2024 |
| A&T-Eps AS | Professional & scientific | 2023 |
| A's Clothing Da | Manufacturing | 2018 |
| A+ Varmepumper AS | Construction | 2015 |
| A-2 Norge AS | Professional & scientific | 2003 |
| A-Ark AS | Professional & scientific | 2018 |
| A-B Bygg Og Malertjeneste AS | Construction | 2012 |
| A-B Eiendom AS | Real estate | 2017 |
| A-Bad AS | Wholesale & retail | 1991 |
| A-Circle AS | Professional & scientific | 2000 |
| A-Consult Agro A/S Nuf | Wholesale & retail | 2009 |
| A-Dventures AS | | 2024 |
| A-E Holding AS | Hospitality | 2022 |
| A-Fa Holding AS | | 2021 |
| A-Fmcg AS | Professional & scientific | 2019 |
| A-Gross AS | Wholesale & retail | 1998 |
| A-Home Group AS | Information & communication | 2021 |
| A-Kurator AS | Hospitality | 2023 |
| A-Lab AS | Professional & scientific | 2000 |
| A-Lab Holding AS | Professional & scientific | 2014 |
| A-Leger AS | Real estate | 2018 |
| A-Li Drabanten AS | Hospitality | 2016 |
| A-Li Dronningen AS | Real estate | 2023 |
| A-Li Group AS | Hospitality | 2023 |
| A-Li Kantinedrift AS | Hospitality | 2023 |
| A-Lister Consulting Services AS | Education | 2020 |
| A-Maskin AS | Wholesale & retail | 1998 |
| A-Membran AS | Construction | 2012 |
| A-Møbler AS | Wholesale & retail | 1985 |
| A-One AS | Information & communication | 2021 |
| A-One Beauty AS | Health & social care | 2024 |
| A-Rail AS | Administrative & support | 2014 |
| A-Seafood AS | Wholesale & retail | 2024 |
| A-T Eiendom AS | Real estate | 2011 |
| A-T Invest AS | | 2020 |
| A-Tanchecenter AS | Education | 2012 |
| A-Team Enterprice AS | Construction | 2025 |
| A-Team Entreprenør AS | Construction | 2022 |
| A-Team Trafikkskole AS | Education | 2014 |
| A-Til-Å AS | Transport & logistics | 2026 |
| A-Tract AS | Professional & scientific | 2010 |
| A-Trola AS | Wholesale & retail | 2016 |
| A-Vinduet AS | Wholesale & retail | 2024 |
| A-Z Byggeservice Idczak AS | Construction | 2016 |