| Connect Grip Ltd | Construction | 2018 |
| Connect Installment Ltd | Wholesale & retail | 2024 |
| Connect to Evolve Limited | Professional & scientific | 2025 |
| Connected Companions UK Ltd | Health & social care | 2026 |
| Connection Community CIC | Other services | 2026 |
| Connex Payments Ltd | Information & communication | 2013 |
| Conrad Fernandes Consultancy Limited | Administrative & support | 2016 |
| Consilium Project Management Ltd | Administrative & support | 2026 |
| Consmedi Ltd | Wholesale & retail | 2024 |
| Constantin Curier Ltd | Construction | 2020 |
| Construct X Ltd | Construction | 2023 |
| Construction Flow Ltd | Construction | 2024 |
| Construction Work London Ltd | Construction | 2025 |
| Consuldent Limited | Professional & scientific | 2019 |
| Consultancy for Properties Ltd | Professional & scientific | 2026 |
| Consultancy Services NAH Ltd | Professional & scientific | 2023 |
| Consulting View Ltd | Professional & scientific | 2013 |
| Contemporary Living Accommodations Ltd | Real estate | 2020 |
| Content Creation Girlies Ltd | Professional & scientific | 2024 |
| Content Marketing POD Ltd | Professional & scientific | 2019 |
| Continental Aviation Services (UK) Ltd | Transport & logistics | 2013 |
| Contract IT 75 Ltd | Information & communication | 2014 |
| Contracts & Procurement Limited | Professional & scientific | 2015 |
| Cookware to Infinity Ltd | Wholesale & retail | 2025 |
| Coolaid Air Conditioning Limited | Energy | 2006 |
| Cooper Ryan Ltd | Construction | 2025 |
| Copabrazil Limited | Hospitality | 1997 |
| Cope Hill Wines Ltd | Wholesale & retail | 2017 |
| Coral Bridging Limited | Financial services | 2020 |
| Coraline Close Residents Association Limited | Households | 1997 |
| Corbyn ST Limited | Real estate | 2021 |
| Corbyn ST Management Limited | Real estate | 2021 |
| Core 1 LLP | | 2009 |
| Core 2 LLP | | 2010 |
| Core Building Supplies Ltd | Wholesale & retail | 2025 |
| Core Security Group Ltd | Administrative & support | 2019 |
| Core Security Sentinel Solutions Ltd | Administrative & support | 2025 |
| Core Stem Concepts Ltd | Education | 2022 |
| Corelate Limited | Professional & scientific | 2017 |
| Corema Limited | Real estate | 2024 |
| Corevia Payments Ltd | Professional & scientific | 2025 |
| Corfu Villas Group Limited | Wholesale & retail | 2025 |
| Corgel Limited | Real estate | 2025 |
| Corgel Property Limited | Real estate | 2025 |
| CORMEL2 Ltd | Financial services | 2022 |
| Cornerstone Business Turnaround and Recovery Limited | Professional & scientific | 2013 |
| Corpium Ltd | Information & communication | 2025 |
| Corporate Relating Limited | Extraterritorial | 2017 |
| Cosgun Consultancy Limited | Professional & scientific | 2019 |
| Cosmetics Planet UK Ltd | Wholesale & retail | 2022 |
| Cosmopolitan Law Ltd | Professional & scientific | 2018 |
| Cosmos Grey Ltd | Wholesale & retail | 2022 |
| Cosmos Healthcare Ltd | Health & social care | 2018 |
| Costa Architecture Limited | Construction | 2016 |
| Costella Inspections Limited | Administrative & support | 2022 |
| Costscutters Ltd | Agriculture & fishing | 2022 |
| Cosway Estate Offices Limited | Real estate | 1995 |
| Cosway Property Group Ltd | Construction | 2025 |
| Cotext Limited | Information & communication | 2016 |
| Cother Consultancy Ltd | Professional & scientific | 2015 |
| Cottage Fields Barnet Ltd | Real estate | 2024 |
| Cottage Fields Developments Limited | Real estate | 2017 |
| Cottage Fields Estates Limited | Real estate | 2015 |
| Cottage Fields Limited | Real estate | 2012 |
| Cotton Loft House Ltd | Real estate | 2025 |
| Cotton Premier Ltd | Wholesale & retail | 2019 |
| Council of Turkish Cypriot Associations UK Events CIC | Other services | 2026 |
| Countrywide Training Limited | Education | 2016 |
| County Services Limited | Information & communication | 2016 |
| County Web Limited | Information & communication | 2017 |
| Courageous Donuts Ltd | Professional & scientific | 2023 |
| Cousins Properties and Investment Ltd | Real estate | 2026 |
| Cov-A-Blind Ltd | Wholesale & retail | 2013 |
| Cover Cars Ltd | Wholesale & retail | 2026 |
| Coville Services Limited | Transport & logistics | 2022 |
| Cozer Ltd | Wholesale & retail | 2025 |
| Cozy Corner Care Limited | Health & social care | 2024 |
| Cozycorner Homes Ltd | Real estate | 2023 |
| CP Education Ltd | Other services | 2023 |
| CP Windows Limited | Manufacturing | 2025 |
| Cpcp Group Limited | Administrative & support | 2019 |
| Cpmhs Consultancy Ltd | Administrative & support | 2024 |
| CPS Roofing Limited | Construction | 2019 |
| CPW Veterinary Services Ltd | Professional & scientific | 2023 |
| Cpwin Ltd | Information & communication | 2024 |
| CR Stays Ltd | Hospitality | 2025 |
| Craft Construction Ltd | Construction | 2011 |
| Craft D&B Ltd | Construction | 2024 |
| Craftman Trading Ltd | Wholesale & retail | 2016 |
| Craftoria Ltd | Wholesale & retail | 2024 |
| Crafty Kids Textile FUN Ltd | Education | 2023 |
| Cranbury Properties Limited | Real estate | 1989 |
| Crane Healthcare Limited | Real estate | 2026 |
| Cranford Barns Management Company Limited | Professional & scientific | 2008 |
| Cranview Ltd | Construction | 2023 |
| Crave Cuisine Limited | Hospitality | 2020 |
| Craving Mediterranean Limited | Wholesale & retail | 2019 |
| Crawford Edge Property Ltd | Real estate | 2024 |
| Craze Trade Limited | Wholesale & retail | 2011 |
| CRE4TE Ltd. | Construction | 2016 |