| Amedia Russian Media AS | Arts & recreation | 2000 |
| Amedia Salg Og Marked AS | Professional & scientific | 2000 |
| Amek Holding AS | | 2026 |
| Amelea AS | Real estate | 2011 |
| Amella Holding AS | | 2025 |
| Amend.World AS | Professional & scientific | 2019 |
| Amendo Group AS | Wholesale & retail | 1998 |
| Ameneon AS | Arts & recreation | 2025 |
| Amenities AS | | 2025 |
| Amenitique Norge AS | Wholesale & retail | 1996 |
| Amentum Eiendom AS | Real estate | 2017 |
| Amentum Multiconsult Decommissioning Ans | Professional & scientific | 2023 |
| Amera Holding AS | Information & communication | 2020 |
| Amergos Group AS | | 2016 |
| Ameri Entreprenør AS | Transport & logistics | 2026 |
| America Dom-Management Limited Nuf | Information & communication | 2015 |
| American Bistro Scandinavia AS | Hospitality | 2002 |
| American Bureau of Shipping Nuf | Professional & scientific | 1995 |
| American Burgers Kiellands Plass AS | Hospitality | 2024 |
| American Express Europe S.A. Nuf | Financial services | 2018 |
| American Holidays AS | Administrative & support | 2009 |
| American Lincoln Norge AS | Wholesale & retail | 1973 |
| American Sportswear AS | Wholesale & retail | 2020 |
| American Wholesale AS | Wholesale & retail | 2024 |
| Americana Skarnes AS | Hospitality | 2022 |
| Amert AS | Financial services | 2005 |
| Amesto Accounthouse AS | Professional & scientific | 1990 |
| Amesto Accounthouse Holding AS | Professional & scientific | 1986 |
| Amesto Aces AS | Information & communication | 2021 |
| Amesto Beyond AS | Professional & scientific | 2008 |
| Amesto Group AS | Administrative & support | 1997 |
| Amesto People & Culture AS | Professional & scientific | 2025 |
| Amesto People Technology AS | Information & communication | 2018 |
| Amet & Partners AS | Wholesale & retail | 2019 |
| Ameta III AS | Financial services | 2007 |
| Ameta Invest AS | Professional & scientific | 1996 |
| Ametas Ans | Wholesale & retail | 2009 |
| Amex Flowers Ans | Wholesale & retail | 1998 |
| Amf.Md AS | Health & social care | 2024 |
| Amfi Invest AS | Real estate | 2005 |
| Amfitrite Produksjon AS | Information & communication | 2021 |
| Amg Consulting AS | Real estate | 2020 |
| Amgen (Europe) AG | Professional & scientific | 2004 |
| Amgen AB Norge Norsk Avdeling Av Utenlandsk Foretak Nuf | Wholesale & retail | 2000 |
| Amhesc Holding AS | | 2023 |
| Amholmeide AS | Financial services | 2005 |
| Amhy Holding AS | Real estate | 2015 |
| Ami Biogas International AS | Energy | 2025 |
| Ami Hår Og Hud AS | Other services | 1964 |
| Ami Invest AS | Construction | 2015 |
| Ami Oslo AS | Hospitality | 2026 |
| Ami Prosjekt AS | Construction | 2023 |
| Amia (Am Interactive Arts) AS | Information & communication | 2013 |
| Amica Revisjon AS | Professional & scientific | 2014 |
| Amicitia AS | | 2014 |
| Amicitia Holding AS | | 2023 |
| Amiculous Holding AS | | 2022 |
| Amidays AS | Information & communication | 2016 |
| Amigos Creative Space AS | Real estate | 2025 |
| Amigostjenester AS | Construction | 2026 |
| Amigotjenester AS | Construction | 2021 |
| Amili Collection AS | Administrative & support | 2002 |
| Amin AS | Information & communication | 2022 |
| Amino AS | Health & social care | 2023 |
| Aminor Holding AS | | 2024 |
| Aminova Holding AS | | 2025 |
| Aminova Invest AS | Real estate | 2025 |
| Aminova Retail AS | Wholesale & retail | 2025 |
| Aminvest AS | | 2023 |
| Amiri Invest AS | | 2006 |
| Amisol Travel AS | Administrative & support | 2002 |
| Amitis AS | Financial services | 2017 |
| Amka AS | Wholesale & retail | 1970 |
| Amkt Holding AS | Financial services | 2017 |
| Aml App AS | Information & communication | 2019 |
| Amland Vivere AS | | 2022 |
| Amlie Holding AS | | 2025 |
| Amma AS | Education | 2026 |
| Amma Holding AS | | 2021 |
| Amma Invest AS | Real estate | 2005 |
| Ammerud BRL Hjemmel AS | Real estate | 2022 |
| Ammerud Fysioterapi AS | Health & social care | 2012 |
| Ammerud Tannlegevakt AS | Health & social care | 2009 |
| Ammerud Yoga AS | Arts & recreation | 2026 |
| Ammerudveien 19-25 AS | Real estate | 2015 |
| Ammerudveien 19-25 Næring AS | Real estate | 2024 |
| Ammobia AS | Professional & scientific | 2025 |
| Ammoniacarrier AS | Transport & logistics | 2018 |
| Ammonite AS | Professional & scientific | 2023 |
| Ammoura Holding AS | Professional & scientific | 2016 |
| Amn Invest AS | | 2021 |
| Amn Investering AS | | 2026 |
| Amnt AS | Other services | 2017 |
| Amo Norway AS | Wholesale & retail | 2002 |
| Amo-Holding AS | Agriculture & fishing | 2022 |
| Amo-Invest AS | Professional & scientific | 2016 |
| Amobility AS | Transport & logistics | 2018 |
| Amoena Norge AS | Wholesale & retail | 2007 |
| Amok AS | Other services | 2013 |
| Amoli Holding AS | | 2018 |