| Anja Stokke AS | Professional & scientific | 2026 |
| Ankerløkka Utvikling AS | Real estate | 2019 |
| Ankerløkken Invest AS | Administrative & support | 2001 |
| Ankerskogen Idrettshall AS | Arts & recreation | 1995 |
| Ankerskogen Kafe AS | Hospitality | 2016 |
| Ankerskogen Legesenter Da | Health & social care | 2011 |
| Ankerveien 90 AS | Real estate | 2016 |
| Anne Østbye Holding AS | | 2018 |
| Anno 09 AS | Hospitality | 2009 |
| Ans Basarene Hamar | Real estate | 1989 |
| Ans Studio 19 | Information & communication | 1976 |
| Aos Invest AS | | 2005 |
| Aproxima AS | Information & communication | 2019 |
| Arcus Gården AS | Real estate | 2014 |
| Aremark Sør Da | Construction | 2024 |
| Arena Eiendomsutvikling AS | Real estate | 2015 |
| Aria Frisør AS | Other services | 2019 |
| Arild Odden AS | Professional & scientific | 2005 |
| Arild Stana AS | Professional & scientific | 2020 |
| Arkivprodukter AS | Wholesale & retail | 2005 |
| Arne Børresen AS | Manufacturing | 2011 |
| Arne Hansen AS | Information & communication | 2006 |
| Arne Hansen Radio & TV AS | Information & communication | 2013 |
| Arnt Salberg Holding AS | | 2021 |
| Arribatec Cloud AS | Information & communication | 2001 |
| AS Christiesgt 13 | Households | 1948 |
| AS Grønnegaten 92 | Real estate | 1969 |
| AS Hertzbergsgate | Real estate | 1951 |
| AS Lykkeboden | Real estate | 1977 |
| AS Løten Elektro | Construction | 2022 |
| AS Rådgiver Frode Danielsen | Information & communication | 2017 |
| AS Skogveien 10 | Real estate | 1984 |
| AS Torggaten 42 | Real estate | 1985 |
| AS Trym | Real estate | 1991 |
| AS Vato | Real estate | 1970 |
| Asas Arkitektur AS | Professional & scientific | 1989 |
| Askim Utvikling AS | Real estate | 2017 |
| Asla Engineering AS | Information & communication | 2023 |
| Asla Invest AS | Wholesale & retail | 2021 |
| Aslak Bolts Gate 49 AS | Real estate | 1964 |
| Aslak Boltsgt 41 AS | Real estate | 2011 |
| Aspen Eiendomsinvest AS | Real estate | 2006 |
| Aspens Gruppen AS | Real estate | 2026 |
| Astoria Blomster AS | Wholesale & retail | 2008 |
| Atc Kantiner AS | Hospitality | 2025 |
| Atelier Rogne AS | Professional & scientific | 2024 |
| Audioguide AS | Professional & scientific | 2004 |
| Audun Nygaard AS | Health & social care | 2015 |
| Aumami AS | | 2024 |
| Aura Holding AS | | 2012 |
| Aura Solutions AS | Information & communication | 2006 |
| Aura Studio Group AS | Other services | 2026 |
| Aurea AS | | 2026 |
| Autosentrum Hamar AS | Wholesale & retail | 2007 |
| Autovault AS | Wholesale & retail | 2017 |
| AV1 Lyd, Lys & Scene AS | Arts & recreation | 2013 |
| Avspark AS | Hospitality | 2012 |
| Awk Helse AS | Health & social care | 2016 |
| Axento AS | Professional & scientific | 2025 |
| B-T Invest AS | | 2025 |
| B. a. Holding AS | Wholesale & retail | 2018 |
| B. Invest AS | | 2025 |
| B.A Optikk Norway AS | Wholesale & retail | 2013 |
| B.A. Eiendom AS | Real estate | 2013 |
| Ba Optikk AS | Wholesale & retail | 2011 |
| Badlybad Games AS | Information & communication | 2024 |
| Baj Consulting AS | Information & communication | 2026 |
| Baj Investeringer AS | | 2026 |
| Bakke-Nett AS | Other services | 2014 |
| Bakken & Brun Ans | Wholesale & retail | 2001 |
| Bakkensgate 1 AS | Real estate | 2022 |
| Balberg Eiendom AS | Real estate | 2021 |
| Balder Invest AS | Professional & scientific | 2011 |
| Baldis AS | Information & communication | 2016 |
| Ballo Invest AS | Real estate | 2025 |
| Ballroom Hamar AS | Hospitality | 2014 |
| Bambini Montessoribarnehage AS | Education | 2002 |
| Bar B Que AS | Hospitality | 2025 |
| Barber King AS | Other services | 2021 |
| Bardak AS | Real estate | 2014 |
| Basarene Restaurant AS | Hospitality | 2025 |
| BB Sport Holding AS | | 2026 |
| Beerpal AS | Wholesale & retail | 2015 |
| Beias Gruppen AS | Real estate | 2002 |
| Bekkeli Park AS | Real estate | 2018 |
| Bekkeliveien 2 AS | Real estate | 1997 |
| Bensin Øst AS | Wholesale & retail | 2016 |
| Bente M. Vestues AS | Professional & scientific | 2011 |
| Bergsten AS | | 2024 |
| Berit's Frisørsalong Da | Other services | 2016 |
| Bertelsen Music AS | Arts & recreation | 2016 |
| Bes Rasmussen AS | Financial services | 2005 |
| Best Outlet AS | Administrative & support | 2019 |
| BG1 Invest AS | Construction | 2018 |
| Bianca Hårdesign AS | Other services | 2015 |
| Biljardn Ans | Arts & recreation | 1992 |
| Bilkompaniet AS | Other services | 1992 |
| Billakkspesialisten Hamar AS | Wholesale & retail | 1978 |
| Biobank AS | Professional & scientific | 2005 |
| Biofocus AS | Wholesale & retail | 2024 |