| Ase Innovations Group AS | Wholesale & retail | 2023 |
| Asfalt Og Lab AS | Professional & scientific | 2026 |
| Asiabutikken K-Berg AS | Wholesale & retail | 2013 |
| Askeladden 4 AS | Real estate | 2022 |
| Askeladden 5 Ans | Real estate | 2002 |
| Askeladden AS | Real estate | 1996 |
| Asklepios AS | Real estate | 1988 |
| Askmo AS | Manufacturing | 2021 |
| Asra Holding AS | Real estate | 2005 |
| Assol Holding AS | | 2021 |
| Astro Precision AS | Information & communication | 2023 |
| Asvo-Kongsberg AS | Health & social care | 1989 |
| At&S AS | Wholesale & retail | 2008 |
| Atle Hope AS | Real estate | 2009 |
| Audere Est Facere 2 AS | Information & communication | 2021 |
| Audere Est Facere AS | Professional & scientific | 2005 |
| Audun Hansen Holding AS | | 2005 |
| Augmented Systems Engineering AS | Professional & scientific | 2022 |
| Autexo AS | Wholesale & retail | 2014 |
| B Stordalen Holding AS | | 2021 |
| B.J. Holding AS | Financial services | 2005 |
| B:Zar AS | Other services | 2010 |
| Bajak | Construction | 2007 |
| Baneveien 32B Eiendom AS | Real estate | 2017 |
| Baneveien Eiendom AS | Real estate | 1998 |
| Barbarossa Holding AS | Real estate | 2017 |
| Bare Rent AS | Administrative & support | 2024 |
| Bare Vin AS | Wholesale & retail | 2012 |
| Barneskatter Kongsberg AS | Wholesale & retail | 2021 |
| Basserudåsveien 7 AS | Real estate | 2015 |
| Bd-Eiendom AS | Real estate | 2005 |
| Bedre Nettsider AS | Information & communication | 2021 |
| Bedriftsplassen AS | Professional & scientific | 2013 |
| Befrielse Ved Kristus AS | Information & communication | 2026 |
| Benrox AS | Construction | 2018 |
| Bente & Jan Kopperud Ans | Education | 1998 |
| Berg Holding Kongsberg AS | Financial services | 2012 |
| Berg Vigdal AS | Professional & scientific | 2026 |
| Bergan & Sand Skogsdrift AS | Agriculture & fishing | 2021 |
| Bergerud-Eiendom AS | Real estate | 2009 |
| Bergmannen Næringspark AS | Real estate | 1983 |
| Bergmanns Bygg AS | Construction | 2014 |
| Bergstory Holding AS | | 2022 |
| Berja Invest AS | Hospitality | 2014 |
| Berja Tannklinikk AS | Health & social care | 2024 |
| Berkana Invest AS | Professional & scientific | 2022 |
| Bernti's Billakkering AS | Other services | 2010 |
| BF Kongsberg Da | Administrative & support | 2025 |
| Bi Pro AS | Information & communication | 2020 |
| Bibbis Frisørstue AS | Other services | 2021 |
| Biinntekt AS | Agriculture & fishing | 2019 |
| Bikers Innovision AS | Administrative & support | 2019 |
| Bilblink AS | Wholesale & retail | 2023 |
| Bildeleksperten AS | Wholesale & retail | 2017 |
| Bilgatti AS | Wholesale & retail | 2016 |
| Bilget AS | Wholesale & retail | 2025 |
| Bilsenteret SA | Real estate | 1975 |
| Bilxtra Autogården Kongsberg AS | Other services | 2014 |
| Bisbas Holding AS | | 2025 |
| Bjarne Buen AS | Construction | 2005 |
| Bjerke Akupunktur AS | Health & social care | 2021 |
| Bjorol AS | Financial services | 2015 |
| Bjørk Eiendom AS | Financial services | 2005 |
| Bjørløw Holding AS | Real estate | 2007 |
| Bjørvassveien SA | Real estate | 2017 |
| BKB 2A T02 AS | Real estate | 2021 |
| BKB 2A T04 AS | Real estate | 2021 |
| Blabla AS | Real estate | 2013 |
| Blefjell Hytteservice AS | Administrative & support | 2021 |
| Blefjellhyttas Venner SA | Real estate | 1993 |
| Blitrygg AS | Information & communication | 2021 |
| Blue Capital AS | | 2021 |
| Blue Subsea AS | Professional & scientific | 2019 |
| Blånuten Eiendom Da | Real estate | 2010 |
| Blånuten Invest AS | Real estate | 2012 |
| Bo's Consulting AS | Professional & scientific | 2022 |
| Bogar AS | Financial services | 2005 |
| BOH19 AS | Construction | 2019 |
| Bold Binary AS | Information & communication | 2018 |
| Bolkesjø Elektro AS | Administrative & support | 2019 |
| Borge Marketing AS | | 1985 |
| BR Haukland AS | Wholesale & retail | 2017 |
| Branncellebegrensende Bygningselementer AS | Professional & scientific | 2024 |
| Brave AS | Administrative & support | 2009 |
| Bros Kafe Og Bar AS | Hospitality | 2024 |
| Broto AS | Real estate | 2007 |
| Brumle AS | Financial services | 2005 |
| Bryn Bydrift AS | Administrative & support | 2012 |
| Bryn Holding AS | Real estate | 2012 |
| Brødr Throndsen AS | Wholesale & retail | 1922 |
| Brødrene Dekkerhus AS | Wholesale & retail | 2023 |
| Bster AS | | 2026 |
| Bto Eiendom AS | Real estate | 2017 |
| Buen Service AS | Professional & scientific | 2007 |
| Buskerud Anlegg AS | Wholesale & retail | 2016 |
| Buskerud Dykkerservice AS | Construction | 2018 |
| Buskerud Eiendom AS | Professional & scientific | 2021 |
| Buskerud Prosjekt Partner AS | Administrative & support | 2009 |
| Buskerud Syn Og Synsfunksjon AS | Health & social care | 2013 |
| Buskerud Tak Og Bygg AS | Construction | 2026 |