| Buyline Holding AS | | 2017 |
| Byala AS | Real estate | 2007 |
| Bye Holding AS | Professional & scientific | 2024 |
| Bygg Og Borr AS | Construction | 2006 |
| Bygg Og Leie AS | Real estate | 2024 |
| Bærum Øre- Nese- Halsklinikk AS | Health & social care | 2009 |
| C-Loop AS | Water & waste | 2023 |
| C64 Eiendom AS | Real estate | 2006 |
| C64 Utleie 1 AS | Real estate | 2006 |
| C64 Utleie 2 AS | Real estate | 2006 |
| Caldic Norway AS | Wholesale & retail | 2000 |
| Calpro AS | Professional & scientific | 1993 |
| Camabeni AS | | 2016 |
| Canacas AS | Real estate | 2009 |
| Capeomega Gas Transportation AS | Transport & logistics | 2020 |
| Capital Control AS | Information & communication | 2013 |
| Carbon Circle Holding AS | Professional & scientific | 2022 |
| Care IT AS | Professional & scientific | 2020 |
| Carma Auto AS | Wholesale & retail | 2021 |
| Caterman AS | Hospitality | 1997 |
| Cautus Geo AS | Professional & scientific | 2009 |
| Cautus Holdco AS | Professional & scientific | 2021 |
| CB Nordisk Holding AS | Wholesale & retail | 2014 |
| CCR AS | | 2021 |
| Ceataec AS | | 2023 |
| Cedrico AS | Manufacturing | 2012 |
| Cedrico Global AS | Wholesale & retail | 2007 |
| CEMA Kunstdistribusjon ANS | Wholesale & retail | 1988 |
| Cemi AS | Financial services | 2005 |
| Cenera AS | Wholesale & retail | 2008 |
| Centra Høvik Eiendom AS | Real estate | 2021 |
| Cerner Norge AS | Wholesale & retail | 2014 |
| CGH AS | Information & communication | 2020 |
| Charge Supply AS | Wholesale & retail | 2008 |
| Check Point Software Technologies Norway AS | Information & communication | 2000 |
| Chevron Services Norway AS | Professional & scientific | 2018 |
| Chill Emotions AS | Administrative & support | 2022 |
| Christian Marc Eichrodt | Information & communication | 2004 |
| Christiania Belysning AS | Wholesale & retail | 1989 |
| Christiania Eiendom Holding AS | Construction | 2005 |
| Christopher Aalholm AS | | 2021 |
| Cirkel Reklamebyrå Ans | Professional & scientific | 1995 |
| Cisco International Limited, Norway Branch | Information & communication | 2021 |
| Cisco Norway AS | Information & communication | 2012 |
| Cisco Norway Holdings AS | Information & communication | 2009 |
| Cisco Systems Inc | Information & communication | 2010 |
| Cisco Systems Norway AS | Information & communication | 1997 |
| Cisco Wood Norway Holdings AS | Information & communication | 2023 |
| Cits V Service (Norway) AS | Professional & scientific | 2019 |
| CKC Holding AS | | 2026 |
| Claims Link AS | Financial services | 1998 |
| Clara Ventures AS | Professional & scientific | 2021 |
| Clean Energy Group AS | Professional & scientific | 2012 |
| Clean Energy Invest AS | Mining & quarrying | 2010 |
| Cloetta Norge AS | Wholesale & retail | 2005 |
| Clothing AS | Wholesale & retail | 2004 |
| CM Capital AS | | 2018 |
| CMP Invest AS | Real estate | 2020 |
| Cobuilder AS | Information & communication | 1997 |
| Cobuilder Group AS | | 2024 |
| Cognite Us Holding AS | Information & communication | 2022 |
| Cognizant Accounting Services Norway AS | Professional & scientific | 2016 |
| Cognizant Business Services Norway AS | Information & communication | 2012 |
| Cognizant Oil and Gas Consulting Services Norway AS | Information & communication | 2002 |
| Cognizant Technology Solutions Norway AS | Information & communication | 2005 |
| Colifast AS | Professional & scientific | 1999 |
| Collectia AS | Administrative & support | 2016 |
| Collectia Norge Holding AS | Administrative & support | 2019 |
| Colsi I AS | Financial services | 2009 |
| Columbia Shipmanagement Norway AS | Transport & logistics | 2023 |
| Comamoc AS | Information & communication | 2014 |
| Commfides Norge AS | Information & communication | 2005 |
| Commitment AS | Information & communication | 2004 |
| Commitment Holding AS | Professional & scientific | 2004 |
| Compax Solutions AS | Professional & scientific | 2017 |
| Compete Consulting Group AS | Professional & scientific | 2018 |
| Compugroup Medical Norway AS | Information & communication | 1993 |
| Concrete Structures AS | Professional & scientific | 2010 |
| Consisu AS | Professional & scientific | 2012 |
| Consvalt Consulting AS | Professional & scientific | 2022 |
| Contendo AS | Information & communication | 1998 |
| Continuum Property AS | Real estate | 1995 |
| Continuum Services AS | Real estate | 2012 |
| Coor Cleaning Catering and Property AS | Administrative & support | 2013 |
| Coor Offshore AS | Professional & scientific | 2014 |
| Coor Service Management Øst AS | Administrative & support | 1975 |
| Coral Invest AS | Real estate | 2022 |
| Craft Drinks AS | Wholesale & retail | 2016 |
| Crobocom AS | Information & communication | 2008 |
| Crossfit Lilleaker AS | Education | 2024 |
| CRR Invest AS | | 2026 |
| Ctrl IT AS | Wholesale & retail | 2006 |
| Cuveco AS | Transport & logistics | 2001 |
| Cyient Norway AS | Professional & scientific | 2006 |
| D'Et Cannes Chez AS | Manufacturing | 2020 |
| Dag 2 AS | Other services | 2023 |
| Dag Peter Og Sture Eiendom AS | Real estate | 2005 |
| Dagfinn H Jørgensen Rådgivende Ingeniører Mrif AS | Professional & scientific | 2020 |
| Dataserver AS | Information & communication | 2010 |
| Datasteel Midco AS | | 2024 |