| Crilly Construction Ltd | Construction | 2014 |
| Cris MED Ltd | Health & social care | 2018 |
| Crisis Whisperer Ltd | Professional & scientific | 2025 |
| Crisp Ideas Limited | Information & communication | 2006 |
| Crispin Hiley Consulting Limited | Health & social care | 2023 |
| Criss Clothing Limited | Wholesale & retail | 2017 |
| CRISTIANBIB2026 Ltd | Wholesale & retail | 2026 |
| Crmagency Ltd | Construction | 2023 |
| Crofts Property Management Ltd | Other services | 2023 |
| Crohamford Limited | Real estate | 1970 |
| Crom Coaching Ltd | Other services | 2022 |
| Crookham Electrical Services Ltd | Construction | 2016 |
| Crookston Electrical Contractors Limited | Construction | 2015 |
| Crop Crew Ltd | Agriculture & fishing | 2025 |
| Cropware Limited | Information & communication | 2000 |
| Crosby Racing Team Ltd | Arts & recreation | 2026 |
| Crossbow 68 Limited | Education | 2017 |
| Crouchs Ltd | Wholesale & retail | 2009 |
| Crouchs' Kennington Ltd | Wholesale & retail | 2018 |
| Crowbridge Property Ltd | Real estate | 2023 |
| Croweaters Ltd | Wholesale & retail | 2023 |
| Crowflies Communications LLP | | 2013 |
| Crown Contractors (Kent) Limited | Construction | 2022 |
| Crown Lodge Enterprises Ltd | Hospitality | 2015 |
| Crown Pets Ltd | Other services | 2020 |
| Crown Plastics (WYE) Ltd | Manufacturing | 2008 |
| Crown Roofing & Guttering Specialist Ltd | Construction | 2025 |
| Crown Truckers Ltd | Transport & logistics | 2012 |
| Crown View Architecture Ltd | Professional & scientific | 2025 |
| Croxon Whetlor Ltd | Construction | 2020 |
| CRS Resource Limited | Administrative & support | 2008 |
| CRS UK Holdings Limited | Administrative & support | 2009 |
| Cruickshank Carpentry Ltd | Construction | 2022 |
| Cruise Addicted Limited | Information & communication | 2023 |
| Crusta Consultants Limited | Administrative & support | 2007 |
| Crysmall Ltd | Wholesale & retail | 2025 |
| Crystal Audiovideo Ltd | Wholesale & retail | 2002 |
| Crystal Clear Hearing Ltd | Health & social care | 2022 |
| Crystal Clear Home Cleaning Limited | Administrative & support | 2019 |
| Crystal Clearance Services Ltd | Water & waste | 2019 |
| Crystal Home Improvements Ltd | Construction | 2025 |
| CS Property Estates Ltd | Real estate | 2024 |
| Csat Property & Maintenance Limited | Real estate | 2024 |
| Cscs Solutions Limited | Manufacturing | 2026 |
| CSS Facilities Services Ltd | Administrative & support | 2019 |
| CT Takamizawa Consulting Limited | Professional & scientific | 2016 |
| CTC International Media Limited | Information & communication | 2012 |
| CTC Property Investments Ltd | Real estate | 2021 |
| CTG Enterprises Limited | Professional & scientific | 2011 |
| Cthelabels Limited | Wholesale & retail | 2025 |
| CTJ Property (South East) Limited | Construction | 2018 |
| Ctpt Property Limited | Real estate | 2025 |
| CTS Heathrow Limited | Transport & logistics | 2009 |
| Cubed Development Five Limited | Construction | 2024 |
| Cubed Development Four Limited | Construction | 2024 |
| Cubed Development Limited | Construction | 2021 |
| Cubed Development Three Limited | Construction | 2022 |
| Cubed Development Two Limited | Construction | 2022 |
| Cubed Property Limited | Construction | 2018 |
| Cucina Acquisition (UK) Limited | Professional & scientific | 2007 |
| Cucina Finance (UK) Limited | Professional & scientific | 2007 |
| Cucina LUX Investments Limited | Professional & scientific | 2007 |
| Cuephoria Limited | Wholesale & retail | 2024 |
| Cumberland Court (2009) Limited | Households | 2008 |
| Cura Chambers Ltd | Public administration | 2018 |
| Curious Raven Consulting Ltd | Professional & scientific | 2022 |
| Curiovate Ltd | Professional & scientific | 2025 |
| Curry Brickwork Limited | Construction | 2015 |
| Curry Mcdonald Ltd | Financial services | 2015 |
| Curtis Electrical Solutions Ltd | Construction | 2025 |
| Cutter Profilers UK Limited | Other services | 2003 |
| CV Contractors Ltd | Construction | 2016 |
| Cvem Limited | Other services | 2002 |
| CW Carpentry and Joinery Limited | Construction | 2018 |
| CW Groundworks Limited | Construction | 2018 |
| Cwdm Limited | Health & social care | 2024 |
| CWP Plumbing & Bathrooms Ltd | Construction | 2026 |
| CWS Moling Limited | Construction | 2004 |
| CXK | Education | 2002 |
| CXK Careers Limited | Extraterritorial | 2011 |
| CXK Trading Limited | Extraterritorial | 2011 |
| Cycle Circle Limited | Education | 2019 |
| Cycle Community CIC | Education | 2016 |
| Cycle Motion Limited | Professional & scientific | 1995 |
| Cyclops Security Training Ltd | Education | 2026 |
| Cygnet Private Finance Limited | Financial services | 2005 |
| Cyphat Limited | Administrative & support | 2017 |
| Cyphat Properties Ltd | Real estate | 2023 |
| Cyprian Holdings Ltd. | Wholesale & retail | 2019 |
| Cyprom Installations Ltd | Construction | 2026 |
| Cyto-Solutions Limited | Wholesale & retail | 2003 |
| D & a C Rail Limited | Professional & scientific | 2013 |
| D & D Autos (Ashford) Limited | Administrative & support | 2005 |
| D & D Autos (Vehicle Sales) Limited | Wholesale & retail | 2017 |
| D & J Media Limited | Information & communication | 2025 |
| D & K Investment Properties Ltd | Real estate | 2021 |
| D & L Developments (Kent) Ltd | Construction | 2025 |
| D & R Auto Services Limited | Wholesale & retail | 2005 |
| D & S Consultancy Limited | Health & social care | 2017 |
| D & S Landscaping Ltd | Administrative & support | 2025 |