| Coatco Ltd | Construction | 2026 |
| Coats Shelfco (SFD) Limited | Extraterritorial | 1956 |
| Coats Shelfco (SSG) Limited | Extraterritorial | 1928 |
| Cobblers Close RTE Company Limited | Real estate | 2003 |
| COBURG22 Ltd | Professional & scientific | 2022 |
| Coca-Cola Europacific Partners (Initial LP) Limited | Financial services | 2019 |
| Coca-Cola Europacific Partners Great Britain Limited | Manufacturing | 1888 |
| Coca-Cola Europacific Partners Holdings Great Britain Limited | Professional & scientific | 1996 |
| Coca-Cola Europacific Partners Pension Scheme Trustees Limited | Financial services | 1997 |
| Coca-Cola Europacific Partners PLC | Manufacturing | 2015 |
| Coca-Cola Europacific Partners Services Europe Limited | Professional & scientific | 1996 |
| Coco Rico Trans Ltd | Transport & logistics | 2024 |
| Cocobeauty Private Ltd | Wholesale & retail | 2026 |
| Coconoot Ltd | Hospitality | 2024 |
| Codestax Infotech Ltd | Information & communication | 2024 |
| Cognitive Outsourcing UK Limited | Professional & scientific | 2025 |
| Cognitive Solutions Corp Ltd | Information & communication | 2014 |
| Cokers Court Bourne END RTE Company Limited | Households | 2003 |
| Cokers Court Management Co. Limited | Households | 1984 |
| Coleman Building Solutions Ltd | Construction | 2020 |
| Colerne Community Care (Kent) Limited | Professional & scientific | 1992 |
| Colham Property Ltd | Real estate | 2024 |
| Collagen Beauty Limited | Other services | 2012 |
| Collett Studios Ltd | Arts & recreation | 2021 |
| Colliers Court Limited | Real estate | 2018 |
| Colomina Social Care Consultancy Ltd | Professional & scientific | 2024 |
| Colonial Ventures Ltd | Professional & scientific | 2025 |
| Colverd Ltd | Real estate | 2021 |
| Combat Dents Ltd | Wholesale & retail | 2019 |
| Comgen Systems Limited | Manufacturing | 2015 |
| Commerce Bridge (UK) Limited | Hospitality | 2018 |
| Commercial Spring Cleaning Limited | Administrative & support | 2018 |
| Commonwealth Coaches Limited | Transport & logistics | 2007 |
| Communication Corner Ltd | Health & social care | 2022 |
| Community Support Project Limited | Health & social care | 2006 |
| Compass Commercial Investments Limited | Real estate | 2025 |
| Complementary Remedies Limited | Health & social care | 2023 |
| Complete Accounting & Bookkeeping Ltd | Professional & scientific | 2023 |
| Complete Business Installations Limited | Administrative & support | 1994 |
| Complete Care & Enablement Services Ltd | Health & social care | 2006 |
| Complete Engine Solutions Limited | Wholesale & retail | 2025 |
| Complete Interior Design Services Ltd | Professional & scientific | 2020 |
| Complete Pixel Solutions Ltd | Manufacturing | 2022 |
| Compson Electrical Services Limited | Manufacturing | 2011 |
| Computerlaptop Ltd | Wholesale & retail | 2025 |
| Comsys VMS Limited | Information & communication | 2004 |
| Concentric Consulting Ltd | Construction | 2001 |
| Concierge Park & Ride Limited | Transport & logistics | 2025 |
| Concise Limited | Administrative & support | 1997 |
| Concord Design Ltd | Wholesale & retail | 2025 |
| Concord Engineering Services Ltd | Professional & scientific | 2025 |
| Concrete Barrier Hire Ltd | Administrative & support | 2007 |
| Conegra (Residents) Limited | Real estate | 1984 |
| Conference House & Pear Tree House Management Company Limited | Households | 1995 |
| Conference Series LLC Limited | Information & communication | 2015 |
| Conic Bidco Limited | Financial services | 2021 |
| Conic Holdco Limited | Financial services | 2021 |
| Conic Midco Limited | Financial services | 2021 |
| Conic Topco Limited | Financial services | 2021 |
| Coningsby Court Residents Association Limited | Real estate | 1987 |
| Connaught Investments Ltd | Real estate | 2023 |
| Connect Care Ltd | Health & social care | 2018 |
| Connect Group International Ltd | Hospitality | 2024 |
| CONNECT2WEB Limited | Information & communication | 2000 |
| Connected Minds CIC | Education | 2026 |
| Connecting Meadows Limited | Wholesale & retail | 2023 |
| Conquest Personal Care Limited | Wholesale & retail | 2000 |
| Constance Consulting Ltd | Construction | 2015 |
| Constantine Court (Hillingdon) Management Company Limited | Households | 1999 |
| Construct Unite Ltd | Construction | 2024 |
| Construction Division Limited | Construction | 2019 |
| Construction Holdco 1 Limited | Construction | 2014 |
| CONSTRUCTIONWORK.24/7 Limited | Construction | 2025 |
| Construxion Limited | Construction | 2020 |
| Consulat Impérial DU Tzar-An-Tzar Imperator Limited | Public administration | 2021 |
| Consult Health Matters Limited | Health & social care | 2020 |
| Consult JA Ltd | Professional & scientific | 2022 |
| Consumable Parts Ltd | Manufacturing | 2025 |
| Consumer Electronics Limited | Wholesale & retail | 2006 |
| Container Storage Solutions (Delta) Ltd | Transport & logistics | 2025 |
| Container Storage Solutions (Echo) Ltd | Transport & logistics | 2025 |
| Container Storage Solutions (Foxtrot) Ltd | Transport & logistics | 2025 |
| Container Storage Solutions (Golf) Ltd | Transport & logistics | 2025 |
| Container Storage Solutions (Hotel) Ltd | Transport & logistics | 2025 |
| Container Storage Solutions (Kilo) Ltd | Transport & logistics | 2025 |
| Container Storage Solutions (Lima) Ltd | Transport & logistics | 2025 |
| Container Storage Solutions (Mike) Ltd | Transport & logistics | 2025 |
| Continua Limited | Administrative & support | 1994 |
| Continuum Care and Education Group Limited | Professional & scientific | 2006 |
| Control Heating and Air Conditioning Ltd | Manufacturing | 2025 |
| Convena Distribution UK Ltd | Other services | 2025 |
| Convey Logistics Ltd | Transport & logistics | 2009 |
| Conveyancing Auction Ltd | Information & communication | 2025 |
| Cooper Specialist Cars Ltd | Wholesale & retail | 2017 |
| Coopers Court (Shefford) RTM Company Limited | Households | 2008 |
| Coopers Lettings Limited | Real estate | 2009 |
| Coopers Professional Services Limited | Construction | 2016 |
| Copeswood Court Management Company Limited | Real estate | 1993 |
| Copper BEE Holdings Limited | Financial services | 2026 |
| Copytrend Limited | Extraterritorial | 1982 |