| Bygg Og Innredning AS | Construction | 2017 |
| Bygg Og Interiør AS | Construction | 1998 |
| Bygg Og Klima AS | Construction | 2018 |
| Bygg Og Oppussing AS | Construction | 2022 |
| Bygg Og Tømrermester Kristian Johnstad AS | Construction | 2008 |
| Bygg Oslo AS | Construction | 2010 |
| Bygg Oslo Flis&Maler AS | Construction | 2023 |
| Bygg Plus AS | Construction | 2002 |
| Bygg Plus Interiør AS | Wholesale & retail | 2015 |
| Bygg Power AS | Construction | 2021 |
| Bygg Reis Deg AS | Administrative & support | 1990 |
| Bygg Skills AS | Construction | 2013 |
| Bygg Stillas AS | Administrative & support | 2023 |
| Bygg Tjeneste AS | Construction | 2014 |
| Bygg Ulver Da | Construction | 2011 |
| Bygg Vest AS | Real estate | 2016 |
| BYGG252 Eiendom AS | Real estate | 2026 |
| Bygga Eiendom AS | Real estate | 2025 |
| Byggallianse AS | Professional & scientific | 2020 |
| Byggark AS | Real estate | 2016 |
| Byggassistanse Ltd Nuf | Professional & scientific | 2010 |
| Byggbelegg Elvestad AS | Construction | 1995 |
| Byggbra AS | | 2013 |
| Byggconsult - Byggmester Lindstad AS | Professional & scientific | 2018 |
| Byggdan AS | Construction | 2013 |
| Bygge Med Perfeksjon AS | Construction | 2023 |
| Byggebistand AS | Professional & scientific | 1980 |
| Byggebiten AS | Wholesale & retail | 2014 |
| Byggebob Nuf | Transport & logistics | 2008 |
| Byggebox AS | Real estate | 2018 |
| Byggebror AS | Construction | 2022 |
| Byggebygg AS | Construction | 2005 |
| Byggeklossen AS | Construction | 2021 |
| Byggeklossen Grunerløkka AS | Wholesale & retail | 2026 |
| Byggekvalitet AS | Transport & logistics | 2020 |
| Byggemester AS | Construction | 2018 |
| Byggeplanktomta AS | Real estate | 2018 |
| Byggeprosjekt Entreprenør AS | Construction | 2021 |
| Byggesaken AS | Information & communication | 2012 |
| Byggesaksguiden AS | Education | 2024 |
| Byggesaksjuristen AS | Professional & scientific | 2024 |
| Byggesaksrådgivning AS | Professional & scientific | 1997 |
| Byggeservice Lindeberg AS | Construction | 2023 |
| Byggestyring AS | Professional & scientific | 1997 |
| Byggetek AS | Professional & scientific | 2021 |
| Byggevare Eiendom AS | Real estate | 2021 |
| Byggforlaget AS | Information & communication | 1967 |
| Byggforvaltning AS | Real estate | 1979 |
| Bygghjelp Service Ans | Construction | 1993 |
| Bygghåndverk Prosjekt AS | Real estate | 2024 |
| Byggimportøren AS | Wholesale & retail | 2023 |
| Byggingeniørene AS | Professional & scientific | 2023 |
| Bygginvest Berkåk AS | Real estate | 1981 |
| Bygginvest Bjugn AS | Real estate | 2017 |
| Bygginvest Kolvereid AS | Real estate | 2014 |
| Bygginvest Oppdal AS | Real estate | 2013 |
| Bygginvest Røros AS | Real estate | 1996 |
| Bygginvest Støren AS | Real estate | 2013 |
| Bygginvest Verdal AS | Real estate | 1985 |
| Byggioslo.No AS | Construction | 2012 |
| Byggklar AS | Information & communication | 2025 |
| Byggkompaniet AS | Construction | 2020 |
| Byggkonsept AS | Construction | 2025 |
| Byggkontroll AS | Professional & scientific | 2017 |
| Byggkort Nuf | Construction | 2020 |
| Byggline AS | | 2025 |
| Bygglund AS | Construction | 2018 |
| Bygglund Drift AS | Construction | 2025 |
| Byggløven AS | Construction | 2025 |
| Byggmakeriet AS | Construction | 2019 |
| Byggmasters AS | Construction | 2024 |
| Byggmatch AS | Administrative & support | 2026 |
| Byggmax AB Nuf | Wholesale & retail | 2006 |
| Byggmc Holding AS | Construction | 2005 |
| Byggmere.No AS | Wholesale & retail | 2020 |
| Byggmester & Prosjekt AS | Construction | 2025 |
| Byggmester a. Øisang AS | Professional & scientific | 2013 |
| Byggmester Christensens Eftf AS | Construction | 1994 |
| Byggmester Dyrnes AS | Construction | 2016 |
| Byggmester Ek AS | Real estate | 2023 |
| Byggmester Gjermunn Emmerhoff AS | Construction | 2014 |
| Byggmester Gullik AS | Professional & scientific | 2019 |
| Byggmester Jacobsen AS | Construction | 2015 |
| Byggmester Jakobsen AS | Construction | 2002 |
| Byggmester Kai Fallet AS | Construction | 2002 |
| Byggmester Nerli AS | Construction | 2020 |
| Byggmester Neteland AS | Construction | 2015 |
| Byggmester Norge AS | Construction | 2025 |
| Byggmester Sanden AS | Construction | 2025 |
| Byggmester Storkaas AS | Construction | 2023 |
| Byggmester Strømdahl AS | Construction | 2003 |
| Byggmester Tollofsen AS | Construction | 2015 |
| Byggmester Tron Wahl-Westreng AS | Construction | 2016 |
| Byggmester Yngve Sem AS | Construction | 2012 |
| Byggmester/Takstmann Bjørn Aarvik AS | Construction | 2013 |
| Byggmesterkompaniet AS | Construction | 2018 |
| Byggmesterkontoret AS | Professional & scientific | 2008 |
| Byggmesterkontoret Radon AS | Professional & scientific | 2015 |
| Byggmestring AS | Real estate | 2014 |
| Byggmix SA | Wholesale & retail | 1998 |