| Companyone Ltd | Real estate | 2012 |
| Companytwo Ltd | Real estate | 2012 |
| Comparison Systems Ltd | Information & communication | 2013 |
| Compass Ethics Limited | Professional & scientific | 2020 |
| Complete Health Restored Ltd | Health & social care | 2026 |
| Complete Marble Restoration Limited | Construction | 2013 |
| Completed IT Designs Ltd | Information & communication | 2023 |
| Completely Floored Limited | Wholesale & retail | 2000 |
| Compliance Hub Consulting Limited | Professional & scientific | 2018 |
| Computer Computer Computer.Com Limited | Wholesale & retail | 2014 |
| Computer Design Limited | Information & communication | 1987 |
| Computer Support Service Ltd | Information & communication | 2013 |
| Compuvert Ltd | Information & communication | 2017 |
| Concep Group Limited | Professional & scientific | 2006 |
| Concep Holdings Limited | Information & communication | 2018 |
| Concep Limited | Wholesale & retail | 2006 |
| Concept 605 Limited | Information & communication | 2019 |
| Concourse Properties Limited | Real estate | 2023 |
| Concourse Tiling Ltd | Construction | 2018 |
| Connectnpc Limited | Hospitality | 2026 |
| Consero Esher Limited | Construction | 2025 |
| Consero Oaktrees Limited | Construction | 2024 |
| Consero Virginia Water Limited | Construction | 2024 |
| Constrade Limited | Construction | 2017 |
| Consult for Change Ltd | Information & communication | 2018 |
| Consultancy 81 Ltd | Information & communication | 2025 |
| Consultant 24/7 Limited | Health & social care | 2013 |
| Consumation Limited | Professional & scientific | 2007 |
| Contact Developments Limited | Real estate | 1992 |
| Contact France Limited | Administrative & support | 2000 |
| Containment Ltd. | Arts & recreation | 2014 |
| Continental CC Ltd | Wholesale & retail | 2023 |
| Converge Advisors and Associates Ltd | Professional & scientific | 2009 |
| Convex Carpentry Limited | Extraterritorial | 2011 |
| Cool Lady Limited | Professional & scientific | 2017 |
| Cool Runnings Limited | Construction | 2011 |
| Coolhurst Lawn Tennis and Squash Rackets Club | Arts & recreation | 2010 |
| Coombe Convenience Ltd | Wholesale & retail | 2026 |
| Coombe Day Nursery Ltd | Health & social care | 2024 |
| Coombe Interiors Ltd | Wholesale & retail | 2013 |
| Coombe Point Ltd | Information & communication | 2016 |
| Coombe Ridings Residents Association Limited | Households | 1962 |
| Coombe View (Kingston) Management Company Limited | Households | 2019 |
| Coombe Way Limited | Real estate | 2019 |
| Coombe Wood Trading Limited | Hospitality | 2016 |
| Copper and Flux Ltd | Construction | 2024 |
| Copper Leaf - Restaurant & GIN Bar Ltd | Hospitality | 2020 |
| Copper Mountain Consulting Limited | Professional & scientific | 2012 |
| Corben Management Limited | Professional & scientific | 2009 |
| Corbett Orchard Ltd | Information & communication | 2019 |
| Cordillera Limited | Wholesale & retail | 2022 |
| Cordless Group Holdings Limited | Financial services | 2016 |
| Core AV Limited | Construction | 2010 |
| Corewise Ltd | Construction | 2024 |
| Coreworks Installations Ltd | Construction | 2026 |
| Corleone Barbers Ltd | Other services | 2021 |
| Cormun Limited | Professional & scientific | 2024 |
| Cornelius Focused Solutions Limited | Administrative & support | 2016 |
| Corners Cafe Limited | Hospitality | 2023 |
| Cornerstone Office Search Limited | Professional & scientific | 2017 |
| Cornerstone United Ltd | Real estate | 2026 |
| Corphye Ltd | Financial services | 2013 |
| Corporate Publishing Limited | Professional & scientific | 2007 |
| Corporate Readiness Ltd | Professional & scientific | 2023 |
| Corporation Transport (Twickenham) Limited | Other services | 2007 |
| Cosmogo Limited | Wholesale & retail | 2025 |
| Cospace Two Limited | Administrative & support | 2010 |
| Cotswold Court Beeston Ltd | Households | 2013 |
| Cotswold Lifts Limited | Construction | 1990 |
| Cotswold Lifts Servicing Ltd | Professional & scientific | 2013 |
| Cottonwood Development Limited | Hospitality | 2023 |
| Couchy Consulting Limited | Information & communication | 2025 |
| Count on Construct Ltd | Construction | 2024 |
| Countess Marquees Limited | Administrative & support | 2007 |
| County Coachworks Limited | Wholesale & retail | 2024 |
| Courier Control App Limited | Information & communication | 2023 |
| Court Estate(Thames Ditton)Management Company Limited(The) | Households | 1969 |
| COX & Buckles Body Repairs Ltd | Manufacturing | 2007 |
| CP Dent Limited | Extraterritorial | 2015 |
| CPR Flats Limited | Real estate | 2016 |
| CPS Cars Ltd | Wholesale & retail | 2024 |
| CPW Trade Ltd. | Wholesale & retail | 2016 |
| CR Energy Ltd | Administrative & support | 2020 |
| CR Kingston Limited | Real estate | 2022 |
| Crackerjack Sports Limited | Arts & recreation | 2018 |
| Craft Brews Ltd | Manufacturing | 2018 |
| Craft Green Shop Ltd | Wholesale & retail | 2025 |
| Craftpro Ltd | Construction | 2026 |
| Craftteam Ltd | Construction | 2026 |
| Craigside & Highcroft Property Management Limited | Households | 2026 |
| Crail Consulting Ltd | Professional & scientific | 2003 |
| Cranfair Limited | Professional & scientific | 2014 |
| Cranwell-Ward Limited | Real estate | 1997 |
| Crawford Risk Management Ltd | Administrative & support | 2015 |
| Crdr Services Limited | Professional & scientific | 2017 |
| Createz Ltd | Professional & scientific | 2020 |
| Creative Digital Ltd | Wholesale & retail | 2024 |
| Creative Youth | Arts & recreation | 2009 |
| Creativity Software Limited | Information & communication | 2001 |
| Credit Risk and Opportunities Consulting Ltd | Professional & scientific | 2012 |