| Cobhamswimclub Ltd | Education | 2023 |
| Cobwood Tree Services Ltd | Agriculture & fishing | 2015 |
| Code Zero Consulting Limited | Professional & scientific | 2009 |
| Codexfit Ltd | Information & communication | 2025 |
| Coffee Online Group Limited | Wholesale & retail | 2012 |
| Coffee Supplies Direct Limited | Wholesale & retail | 2009 |
| Cognition Management Ltd | Financial services | 2026 |
| Cognition Specialty Ltd | Financial services | 2026 |
| Colemarch Limited | Construction | 2006 |
| Collingwood Management Company (Walton) Limited | Real estate | 1983 |
| Collis Roofing Services Ltd | Construction | 2025 |
| Colorado Blake Developments Ltd | Real estate | 2018 |
| Columbia Investment Consultants Limited | Professional & scientific | 1965 |
| Combat Stress | Health & social care | 1931 |
| Combat Stress Trading Limited | Wholesale & retail | 2011 |
| Combe International Limited | Manufacturing | 1974 |
| Commandeur Consulting Ltd | Professional & scientific | 2019 |
| Commandeur Ltd | Real estate | 2015 |
| Commercial Interior Projects Ltd | Professional & scientific | 2011 |
| Commercial Property Disputes Limited | Professional & scientific | 2011 |
| Comms Multilingual Ltd | Professional & scientific | 2003 |
| Community Sherpa Ltd | Information & communication | 2023 |
| Company of Sixty Field Archers Ltd | Arts & recreation | 2004 |
| Complete Oven Cleaning Surrey Ltd | Administrative & support | 2025 |
| Composite BAT Ltd | Manufacturing | 2026 |
| Computer Care (UK) Limited | Information & communication | 2001 |
| Conch Properties Ltd | Real estate | 2023 |
| Conductor Capital Asset Management LLP | | 2022 |
| Conductor Capital Holdings Limited | Professional & scientific | 2022 |
| Coney Luxury Ltd | Professional & scientific | 2013 |
| Confidosoft Ltd | Information & communication | 2014 |
| Confirma Financial Training Limited | Professional & scientific | 2023 |
| Conifer Court (Wimbledon) Freehold Limited | Households | 2005 |
| Connaught House Bagshot Management Company Limited | Households | 2020 |
| Connect House Leatherhead Limited | Real estate | 2011 |
| Connected Comms Society Ltd. | Information & communication | 2018 |
| Connected Ventures Ltd | Information & communication | 2025 |
| Connections Exhibitions Inc Ltd | Administrative & support | 2012 |
| Connectr Limited | Extraterritorial | 2021 |
| Connolly House (Wimbledon) RTM Company Limited | Households | 2013 |
| Conservaqua Limited | Water & waste | 2019 |
| Conservation Consultants Ltd | Arts & recreation | 2025 |
| Consumer Devotion Limited | Information & communication | 2019 |
| Content Holdings International Ltd | Information & communication | 2006 |
| Conundrum Intelligence Ltd | Information & communication | 2023 |
| Convero Limited | Information & communication | 2014 |
| Cool for School Ltd | Education | 2020 |
| Cool Mimi Ltd | Wholesale & retail | 2024 |
| Coombe Court Tadworth Limited | Households | 2004 |
| Coomber and Coomber Limited | Real estate | 2011 |
| Cooper James Limited | Professional & scientific | 2014 |
| Cooperativa DE Ahorros Creditos Y Servicios Multiples Montajz (Coopmontajz) Ltd | Financial services | 2026 |
| Coppertree Forensics Ltd | Manufacturing | 2013 |
| Copsem Investment Company Limited | Financial services | 1962 |
| Copsen Wood Management Company Limited | Households | 1994 |
| Copthorne Court Management Company Limited | Households | 1989 |
| Corban Limited | Professional & scientific | 1990 |
| Corefin Limited | Professional & scientific | 2016 |
| Corestad UK Ltd | Information & communication | 2022 |
| Corfe Capital Ltd | Real estate | 2008 |
| Cornwell (Home Barn Properties) Limited | Real estate | 2003 |
| Coronation Glen Estate Limited | Real estate | 2013 |
| COS Later Ltd | Wholesale & retail | 2025 |
| Cotribe Incubator CIC | Administrative & support | 2020 |
| Cottage PIE Properties Ltd | Real estate | 2020 |
| Cotterells RG Limited | Real estate | 2017 |
| Country Bakery UK Limited | Financial services | 2022 |
| Country Rhythm Limited | Real estate | 1999 |
| Court Cavendish Healthcare Management Services Limited | Professional & scientific | 2011 |
| Court Cavendish Limited | Professional & scientific | 2001 |
| Courtney Place NO.1 Management Company Limited | Households | 1996 |
| Courtney Place NO.2 Management Company Limited | Households | 1996 |
| Coverpoint Solutions Limited | Information & communication | 1994 |
| Covington Unicorn Ltd | Professional & scientific | 2021 |
| CPC Consulting Ltd | Professional & scientific | 2010 |
| Craigside Holding Company Limited | Financial services | 2026 |
| Cranmore School Enterprises Ltd | Education | 2016 |
| Cray Retail Limited | Wholesale & retail | 2013 |
| Craysell Homes Limited | Health & social care | 1981 |
| Craysell Limited | Health & social care | 1988 |
| Creative Edge Studios Ltd | Information & communication | 2012 |
| Creative Remote Ltd | Information & communication | 2021 |
| Crescent Dental Practice Limited | Health & social care | 2011 |
| Cripplegate Ltd | Real estate | 2016 |
| Crossrealms International (UK) Limited | Information & communication | 2026 |
| Crossways (Sunbury) Management Services Limited | Households | 2006 |
| Crossways Construction Limited | Construction | 2015 |
| Crowded Mind Limited | Information & communication | 2013 |
| Crown House Residence Management Company Limited | Households | 2015 |
| Croydon (Living) LLP | | 2020 |
| Crusader Court (Redhill) Residents Company Limited | Households | 1993 |
| Crystal International Technology Limited | Wholesale & retail | 2025 |
| CS Contractor Services Limited | Construction | 2025 |
| Csam Solutions Limited | Professional & scientific | 2024 |
| CSK Broadcast Engineering Ltd | Extraterritorial | 2010 |
| Ctforensics Ltd | Manufacturing | 2025 |
| Cucina Limited | Hospitality | 2018 |
| Cude Design Limited | Information & communication | 2015 |
| Culture Zone Ltd | Professional & scientific | 2025 |
| Cupa TY Limited | Real estate | 2023 |