| Consult Africa Investment Network Limited | Administrative & support | 2026 |
| Consult SMB Limited | Professional & scientific | 2009 |
| Consulting Lkam Limited | Professional & scientific | 2024 |
| Container Freight Services Limited | Transport & logistics | 2015 |
| Contentency Ltd | Professional & scientific | 2019 |
| Contentsmash Ltd | Professional & scientific | 2021 |
| Continental Commodities Supply Chain Limited | Manufacturing | 2021 |
| Contract Management (UK) Limited | Construction | 2019 |
| CONTRACTORS4 Ltd | Construction | 2024 |
| Contrax Building Services Ltd | Construction | 2014 |
| Contricircle Ltd | Information & communication | 2025 |
| Control Chaos Ltd | Information & communication | 2021 |
| Control First Ltd | Administrative & support | 2025 |
| Controlled Safehome Maintenance Limited | Construction | 2026 |
| Controltake Property Management Limited | Households | 1997 |
| Convalesce Care & Recruitment Ltd | Administrative & support | 2023 |
| Cookes Meadow (Northwich) Management Company Limited | Households | 2015 |
| Cooks Newsagents Limited | Administrative & support | 2002 |
| Cool Heating Ltd | Construction | 2022 |
| Cool IT World Limited | Education | 2009 |
| Cool-Surf Limited | Administrative & support | 2013 |
| Coombe Avenue Investments Limited | Extraterritorial | 1960 |
| Coombe House Developments Ltd | Real estate | 2011 |
| Coombe Lodge RTM Company Limited | Households | 2016 |
| Coombe Road Management Company Limited | Extraterritorial | 2014 |
| Coonley Trading Limited | Construction | 2017 |
| Cooper Coachworks Limited | Wholesale & retail | 2018 |
| Cooper Lodge Management Company Limited | Households | 2005 |
| Cooper Mouldings Ltd. | Administrative & support | 2016 |
| Cooperage Court Ltd | Households | 2018 |
| Coopers Edge (Parcel 8) Management Company Limited | Households | 2014 |
| Coopers Way Residents Association Limited | Households | 1990 |
| Coox & SON Construction Ltd | Construction | 2025 |
| Coppard Builders Ltd | Administrative & support | 2011 |
| Copper Muse Limited | Arts & recreation | 2011 |
| Copperfields Residents Company Limited | Households | 2004 |
| Coppermill Place Management Company Limited | Households | 2000 |
| Coppice Beck Management Company Limited | Households | 2004 |
| Coppice Green Lane Management Company Limited | Households | 2015 |
| Coppice Mews Management Limited | Households | 2007 |
| Copplestone Court Management Limited | Households | 1995 |
| Copthorne Place (Epsom) Apartments Management Company Limited | Households | 2014 |
| Copthorne Place (Epsom) Estate Management Company Limited | Households | 2014 |
| Copywell Limited | Real estate | 2017 |
| Coquillage Limited | Wholesale & retail | 2020 |
| COR Investment Ltd | Real estate | 2014 |
| Coralmoon Limited | Financial services | 2010 |
| Cordomus Limited | Construction | 2021 |
| Core Experts Ltd | Professional & scientific | 2018 |
| Core FIX Solutions Ltd | Wholesale & retail | 2025 |
| Core Fundamentals Ltd | Professional & scientific | 2020 |
| Core House Developments Limited | Real estate | 2026 |
| Core PI Limited | Construction | 2015 |
| Core Risk Consultancy Limited | Administrative & support | 2013 |
| Core Site Management Ltd | Construction | 2015 |
| Corefunnel Limited | Information & communication | 2025 |
| Coreitech Digital Ltd | Wholesale & retail | 2026 |
| Coreitech Ltd | Information & communication | 2024 |
| Corks N KEG Limited | Wholesale & retail | 2023 |
| Corner Hairdressing Limited | Other services | 2021 |
| Corner House (Caterham) Management Company Limited | Households | 2016 |
| Cornerside Residents Association Limited | Households | 1982 |
| Cornerstone Building & Construction Ltd | Construction | 2026 |
| Cornerstone Confidence Coaching Ltd | Health & social care | 2015 |
| Cornerstone International Group Limited | Real estate | 2018 |
| Cornerways Property Investments Limited | Real estate | 2015 |
| Cornerways Trading Limited | Administrative & support | 2018 |
| Cornford Amplification Limited | Professional & scientific | 2008 |
| Corniche (London) Limited | Real estate | 2010 |
| Coronation Court Management Company Limited | Households | 2016 |
| Coronus Limited | Financial services | 2017 |
| Corporate Business Consulting Ltd | Information & communication | 2018 |
| Corporate Installs Limited | Professional & scientific | 2007 |
| Corporate Strategic Partners Ltd | Information & communication | 2020 |
| Corrida & Company International Limited | Wholesale & retail | 2007 |
| Cortex Engineering Limited | Construction | 2018 |
| Corth Properties Investment Ltd | Real estate | 2019 |
| Cortizo UK Limited | Wholesale & retail | 2018 |
| Corvae Ltd | Professional & scientific | 2026 |
| Corvid Consulting UK Ltd | Information & communication | 2013 |
| Corvid Management Ltd | Real estate | 2019 |
| Cosby Convenience Limited | Wholesale & retail | 2019 |
| Coscreation Ltd | Manufacturing | 2022 |
| Cosmic Marketing Ltd | Professional & scientific | 2021 |
| Cosmicai Ltd | Information & communication | 2025 |
| Cosmopolitan Restaurants (UK) Limited | Hospitality | 2009 |
| Cosmos and Plums Ltd | Wholesale & retail | 2025 |
| Cosmuo Ltd | Other services | 2014 |
| Cosmure Ltd | Wholesale & retail | 2026 |
| Costantina Bardis Coaching Ltd | Education | 2022 |
| Costi Solutions Ltd | Construction | 2018 |
| Costive Health Limited | Wholesale & retail | 2026 |
| Cotisation Premium Paiement Ltd | Wholesale & retail | 2025 |
| Cottage Factory Limited | Administrative & support | 2024 |
| Cottage Gate (Management Company) Limited | Households | 2008 |
| Cottesmore Associates Ltd | Information & communication | 2018 |
| Coukson International Investments Corporation Ltd | Administrative & support | 1975 |
| Coulsdon Builders Ltd | Construction | 2022 |
| Coulsdon RST Limited | Other services | 2018 |
| Counselling for ME Limited | Health & social care | 2020 |