| Capeesh Software AS | Information & communication | 2026 |
| Capiens AS | Administrative & support | 2024 |
| Capira Group AS | Information & communication | 2025 |
| Capitool Holding AS | Financial services | 2005 |
| Cappelen Skovholt AS | Professional & scientific | 2008 |
| Capri AS | Hospitality | 2003 |
| Caps Lock Data Da | Wholesale & retail | 1999 |
| Carabasi AS | Real estate | 2015 |
| Careco Midt-Norge AS | Education | 2021 |
| Carica AS | Administrative & support | 2021 |
| Carine Holding AS | | 2026 |
| Carl Johans Gate 10 AS | Real estate | 2026 |
| Carl Johans Gate 5 AS | Real estate | 2023 |
| Carl Johans Gate 8-12 AS | Real estate | 2019 |
| Carl Johans GT 4 AS | Real estate | 1997 |
| Carl Lindhe Invest AS | | 2026 |
| Carl Stuckrath Eftf AS | Wholesale & retail | 1972 |
| Carleif Elektro AS | Construction | 1987 |
| Carleniusai AS | Professional & scientific | 2026 |
| Carma AS | Wholesale & retail | 2003 |
| Caroline Søgaard AS | | 2021 |
| Carpe Diem Vinbar AS | Hospitality | 2025 |
| Carpoint AS | Wholesale & retail | 2023 |
| Carrot Invest AS | | 2021 |
| Carstens Eiendom AS | Real estate | 2006 |
| Carstens Holding AS | Real estate | 2005 |
| Carstens Invest AS | Professional & scientific | 2020 |
| Cartesian AS | Professional & scientific | 2023 |
| Cartography AS | Education | 2026 |
| Carwash Da | Other services | 2001 |
| Casas Los Garroferos | | 2021 |
| Cascata Holding AS | | 2016 |
| Caseweb AS | Information & communication | 2026 |
| Casper Kristoffersen Holding AS | | 2025 |
| Cassiopeia Eiendom AS | Real estate | 2006 |
| Castle Holding AS | Real estate | 2021 |
| Casulo AS | Professional & scientific | 2006 |
| Catbiscuit AS | Information & communication | 2023 |
| Catchphraser AS | Information & communication | 2025 |
| Cate Medical Devices AS | Professional & scientific | 2023 |
| Catelisa AS | Real estate | 2004 |
| Catering Trondheim AS | Hospitality | 2019 |
| Cath Invest AS | Real estate | 2013 |
| Cathrine Dillner Hagen AS | Professional & scientific | 1998 |
| Cati AS | | 2021 |
| Cattley Holdings AS | | 2023 |
| Cavabugen Invest AS | Wholesale & retail | 2020 |
| Cavapsis Holding AS | | 2026 |
| Caviere One Da | Arts & recreation | 2010 |
| CB Rør AS | Construction | 2020 |
| CBJ Computing AS | Professional & scientific | 2017 |
| CBR Holding AS | Real estate | 2005 |
| CBS Invest AS | Professional & scientific | 2005 |
| CC Gardiner AS | Wholesale & retail | 2018 |
| CCP 5 Glasses AS | Real estate | 2018 |
| Cea AS | Wholesale & retail | 2021 |
| Cecil Holding AS | | 2006 |
| Cecilie Løvøs Veg 14 AS | Real estate | 2019 |
| Cecilie Løvøs Veg 2 AS | Real estate | 2014 |
| Cecilienborg Bolig AS | Real estate | 2015 |
| Ceco AS | Professional & scientific | 2009 |
| Ceetron Solutions AS | Information & communication | 2013 |
| Cefem AS | Wholesale & retail | 2006 |
| Celero AS | Professional & scientific | 2005 |
| Celestial Fall Da | Arts & recreation | 2018 |
| Celium AS | Professional & scientific | 2022 |
| Cemaro AS | Transport & logistics | 2018 |
| Cencit AS | Information & communication | 2014 |
| Censor Holding AS | | 2026 |
| CENTER365 AS | Information & communication | 2021 |
| Central Property AS | Real estate | 2019 |
| Centrum Bowling AS | Arts & recreation | 1991 |
| Centrum Da | Arts & recreation | 2026 |
| Centrum Trafikkskole AS | Education | 1995 |
| Cephalo AS | Education | 2025 |
| Cequity AS | | 2021 |
| Ceramics AS | Construction | 2011 |
| Cerebrium AS | | 2026 |
| Cervus Invest AS | Real estate | 2017 |
| Cervus Utvikling AS | Real estate | 2022 |
| Cessare AS | Professional & scientific | 2012 |
| CFC Drive AS | Hospitality | 2017 |
| CFC Norway AS | Wholesale & retail | 2018 |
| Cfmr AS | | 2021 |
| Cfore AS | | 2024 |
| CG Invest AS | Financial services | 2008 |
| Cgo Automasjon AS | Professional & scientific | 2025 |
| CGR Holding AS | Wholesale & retail | 2017 |
| Cgss AS | Professional & scientific | 2020 |
| CH Rørleggervakten Trondheim AS | Construction | 2026 |
| Chaim Holding AS | Professional & scientific | 2021 |
| Charles Music AS | Information & communication | 2021 |
| Charlies Mat Ans | Wholesale & retail | 2001 |
| Charlotte Bjørk Ingul AS | Health & social care | 2005 |
| Charlottenlund Lokalsenter AS | Real estate | 2024 |
| Charlottenlund Senter Eiendom AS | Real estate | 2024 |
| CHB Holding AS | Real estate | 2010 |
| Cheam AS | | 2005 |
| Chef Bernard AS | Hospitality | 2001 |
| Chessality AS | Hospitality | 2021 |