| Cignpost Diagnostics Limited | Health & social care | 2020 |
| Cignpost Financial Services Limited | Administrative & support | 2013 |
| Cignpost Group Limited | Professional & scientific | 2014 |
| Cignpost Services Limited | Financial services | 2014 |
| Circlewood Limited | Information & communication | 2025 |
| Circular Thrift Limited | Wholesale & retail | 2023 |
| Citilet Booking Limited | Hospitality | 2014 |
| Citizens Advice South West Surrey | Other services | 1996 |
| Citygrove Development Services Limited | Real estate | 2015 |
| Citygrove Lubeck Developments Limited | Real estate | 2015 |
| Citygrove Professional Services Limited | Construction | 2012 |
| Citygrove Securities Limited | Real estate | 2003 |
| Citygrove Trustee Limited | Financial services | 2016 |
| CJ the Hollies Ltd | Real estate | 2022 |
| CJDWX2 Limited | Administrative & support | 2024 |
| CJY Consulting Limited | Professional & scientific | 2023 |
| CL58TS Limited | Real estate | 1993 |
| Claim Guardians Limited | Information & communication | 2024 |
| Clarity Accounting Associates Limited | Professional & scientific | 2017 |
| Clarity Communications and Change Consultancy Ltd | Professional & scientific | 2013 |
| Clarkson Medical Consultancy Ltd | Health & social care | 2009 |
| Classic and Historic Racing Club Limited | Administrative & support | 2010 |
| Clausura Limited | Information & communication | 2020 |
| CLB Insights Ltd | Professional & scientific | 2025 |
| Clb-Aesthetic Ltd | Other services | 2026 |
| Clean Automotive Engineering Ltd | Professional & scientific | 2018 |
| Clearly Jobs Limited | Administrative & support | 2007 |
| Clearview Glass Limited | Construction | 2001 |
| Clery & Co Limited | Real estate | 2020 |
| Cleveland Joinery Limited | Manufacturing | 1983 |
| CLF3 Limited | Administrative & support | 2010 |
| Clifftop Computers Limited | Professional & scientific | 1987 |
| Climate Change Professional Association | Professional & scientific | 2023 |
| Climate Dice Limited | Manufacturing | 2026 |
| Cllg Limited | Extraterritorial | 2012 |
| Clock House Limited | Real estate | 2015 |
| Clockbarn Consulting Ltd | Professional & scientific | 2023 |
| Clockwork Production Services Limited | Construction | 2014 |
| Clockwork Scenery Ltd | Construction | 2012 |
| Clorr Properties LLP | | 2017 |
| CLOUD69 Investments Ltd | Financial services | 2021 |
| CLOUD69 Limited | Information & communication | 2019 |
| Clover Path Ltd. | Financial services | 1991 |
| Club 66 Limited | Real estate | 2019 |
| Clueless the Musical Limited | Arts & recreation | 2023 |
| Cmdevelopinvestments Ltd | Real estate | 2017 |
| CMH Productions Limited | Information & communication | 2017 |
| CMI Corporation Limited | Wholesale & retail | 2009 |
| CMI Corporation RN Limited | Wholesale & retail | 2012 |
| CMI Technologies (UK) Ltd | Wholesale & retail | 2026 |
| CMI Technology Ltd. | Wholesale & retail | 1996 |
| CMN Financial Ltd. | Professional & scientific | 2015 |
| Coaching Training & Consulting Europe LLP | | 2009 |
| Coast Racing Limited | Professional & scientific | 1999 |
| Cody Management Services Ltd | Financial services | 2021 |
| Coebergh Medical Ltd | Health & social care | 2019 |
| Coeur Kitchens Ltd | Wholesale & retail | 2018 |
| Cognify Finance Ltd | Administrative & support | 2024 |
| Colin Baldwin Photography Ltd | Professional & scientific | 2012 |
| Collectors Coffee House Ltd | Manufacturing | 2022 |
| Collins Planning & Design Service LLP | | 2019 |
| Collis Crowd Ltd | Arts & recreation | 2024 |
| Colonial Commodities London Ltd | Wholesale & retail | 2018 |
| Combe Rise Limited | Administrative & support | 2015 |
| Combechaud Limited | Professional & scientific | 2004 |
| Combes Estates Limited | Real estate | 2026 |
| Commercial Creativity Limited | Administrative & support | 2008 |
| Commercial Grounds Care Services Limited | Other services | 2002 |
| Communications Project Limited | Professional & scientific | 1994 |
| Communico Corporation Holdings Ltd | Professional & scientific | 2006 |
| Communico Corporation Ltd | Information & communication | 2005 |
| Compasses Trading Ltd | Wholesale & retail | 2023 |
| Competitive Drug Development International Limited | Administrative & support | 2009 |
| Complete Communication Training Limited | Education | 2011 |
| Complete Property Solutions (Surrey) Limited | Other services | 2011 |
| Complex (Building Services) Limited | Construction | 2012 |
| Complex Commercial Ltd | Construction | 2023 |
| Compton Court Residents Association Limited | Households | 1971 |
| Compufile Systems Limited | Information & communication | 1988 |
| Conectia Limited | Professional & scientific | 2008 |
| Congruence Ltd | Information & communication | 2014 |
| Conrero Ltd | Professional & scientific | 2022 |
| Constantine CIP LLP | | 2022 |
| Constantine Energy Limited | Administrative & support | 2010 |
| Constantine Energy Storage Holdco Limited | Administrative & support | 2024 |
| Constantine Energy Storage LLP | | 2022 |
| Constantine Energy Storage Midco LLP | | 2024 |
| Constantine Energy Storage Services Limited | Administrative & support | 2021 |
| Constantine Group Limited | Professional & scientific | 1960 |
| Constantine Holdings Limited | Professional & scientific | 2017 |
| Constantine Land Limited | Real estate | 1937 |
| Constantine Property Management Limited | Real estate | 1944 |
| Constantine Wind Energy Limited | Administrative & support | 2011 |
| Construct MCS Ltd | Construction | 2022 |
| Construction Brokers Limited | | 1980 |
| Contact Centre Management Association Limited | Extraterritorial | 2020 |
| Contender Productions Ltd | Information & communication | 2016 |
| Contour Direct Limited | Professional & scientific | 1995 |
| Coolspeed Limited | Transport & logistics | 1996 |
| Coombe Field Management Limited | Households | 2006 |