| Baca AS | Financial services | 2005 |
| Backer Invest AS | Financial services | 2016 |
| Backfire AS | Financial services | 2014 |
| Backtoback AS | Financial services | 2005 |
| Bagbrokers AS | Wholesale & retail | 2013 |
| Bagbrokers Plus AS | Wholesale & retail | 2024 |
| Bagno Design AS | Construction | 2022 |
| Bai Con AS | Professional & scientific | 2015 |
| Bakketun Consult AS | Professional & scientific | 2006 |
| Balder Forsikring AS | Financial services | 2024 |
| Balder Gruppen AS | Financial services | 2013 |
| Balder Sikkerhet AS | Administrative & support | 2023 |
| Baltic Invest AS | Real estate | 2014 |
| Banak Invest AS | Financial services | 2007 |
| Barolo AS | Professional & scientific | 2024 |
| Barstølveien 5 D AS | Real estate | 1996 |
| Basically AS | Professional & scientific | 2018 |
| Battsack AS | Professional & scientific | 2023 |
| Bauta Eiendomsutvikling AS | Construction | 2020 |
| Baxter of California AS | Wholesale & retail | 2023 |
| Bay Braathen Invest AS | | 2021 |
| Beach Consult AS | Professional & scientific | 2025 |
| Beach Invest AS | | 2025 |
| Beacon Communications AS | Professional & scientific | 2015 |
| Beacon Holding Group Ltd | Administrative & support | 2022 |
| Beacs AS | Financial services | 2005 |
| Beara 793 Holding AS | | 2023 |
| Becker Media AS | Manufacturing | 2008 |
| Bedre Kode AS | Information & communication | 2019 |
| Belafonte AS | | 2021 |
| Bell Bygg AS | Construction | 2026 |
| Bell Invest AS | Financial services | 2021 |
| Bellini Cipriani AS | Real estate | 2020 |
| Benify AS | Information & communication | 2014 |
| Bente Holding AS | Financial services | 2005 |
| Berg & Dahl AS | Wholesale & retail | 2001 |
| Berg Vann Og Avløp SA | Water & waste | 2017 |
| Berg-Jacobsen Holding AS | Real estate | 1996 |
| Berg-Jacobsen Invest AS | Financial services | 2005 |
| Bergans Fritid AS | Manufacturing | 1991 |
| Bergans Norway AS | Wholesale & retail | 2015 |
| Bergans Retail AS | Wholesale & retail | 2015 |
| Bergvang AS | Agriculture & fishing | 2007 |
| Bergvik Holding AS | | 2026 |
| Berna Holding AS | Professional & scientific | 2024 |
| Bestbrand Service AS | Wholesale & retail | 2024 |
| Betajob AS | Information & communication | 2012 |
| Bevolden AS | | 2024 |
| Beyersen AS | Financial services | 2018 |
| BFS Invest AS | | 2025 |
| Bher Invest AS | | 2025 |
| Biashara AS | Financial services | 2011 |
| Bibbi Holding AS | | 2020 |
| Bio-Tech AS | Real estate | 1984 |
| Birdflocks AS | Information & communication | 2020 |
| Bitei AS | | 2022 |
| Biterud Consulting AS | Information & communication | 2019 |
| Bitmain Technologies Norway Limited AS | | 2022 |
| Biwiho AS | | 2025 |
| Bjelke AS | | 2024 |
| Bjelke Holding AS | Professional & scientific | 2005 |
| BJH Holding AS | Financial services | 2014 |
| Bjølstad Invest AS | | 2024 |
| Bjørkli Kurssenter AS | Education | 1998 |
| Bjørn Hermann Tungodden Invest AS | Transport & logistics | 2015 |
| Bjørns Blikk AS | Construction | 2007 |
| Bka Elektro AS | Construction | 2021 |
| Blaaskjæl AS | | 2025 |
| Black and White Engineering AS | Professional & scientific | 2026 |
| Blackline AS | Transport & logistics | 2024 |
| Blacktower Nordic Nuf | Agriculture & fishing | 2014 |
| Blakstadmarka 26 AS | Real estate | 2002 |
| Blanke Ski Invest AS | | 2022 |
| Bleiker Legekontor AS | Health & social care | 2013 |
| Bleiker Mat AS | Wholesale & retail | 2021 |
| Bleikerveien 8 AS | Real estate | 2016 |
| Blichsgate 1 AS | Real estate | 2000 |
| Blichsgt 3 Ans | Real estate | 1988 |
| Blissio Limited Nuf | Information & communication | 2009 |
| Blue Marine AS | | 2017 |
| Blue Tomato Norway AS | Wholesale & retail | 2021 |
| Blue Whale Consulting AS | Professional & scientific | 2026 |
| Blue Yonder Norway AS | Information & communication | 1995 |
| Bluebox AS | Information & communication | 2013 |
| Bluecap AS | | 2025 |
| Blåtand Holding AS | | 2021 |
| Blått Blikk SA | Arts & recreation | 2019 |
| BM 26 Eiendomsinvest AS | Real estate | 2026 |
| Bmax AS | Information & communication | 2018 |
| BMC Helix Norway AS | Professional & scientific | 2025 |
| BMC Software AS | Information & communication | 1998 |
| Bmin AS | Real estate | 2021 |
| Bmo Holding AS | Real estate | 2008 |
| BNC Real Estate & Invest AS | Real estate | 2025 |
| Bo Og Leve AS | Professional & scientific | 2021 |
| Boehringer Ingelheim Danmark A/S Nuf | Wholesale & retail | 2023 |
| Boeing Norway AS | Professional & scientific | 2012 |
| Boeing Norwegian Holdings AS | Professional & scientific | 2006 |
| Bolig Solutions AS | Construction | 2013 |
| Boligberedskap.No AS | Professional & scientific | 2026 |