| Canary Hand Car Wash Limited | Transport & logistics | 2015 |
| Canary Healthcare Limited | Extraterritorial | 2016 |
| Canary Mortgages Limited | Financial services | 2026 |
| Canary Networks Ltd | Real estate | 2020 |
| Canary PUB Co Ltd | Hospitality | 2013 |
| Canary Social Club Ltd | Arts & recreation | 2013 |
| Cancer Community Chest | Health & social care | 1996 |
| Candour Agency Ltd | Professional & scientific | 2013 |
| Candy Bunnies Limited | Other services | 2018 |
| Cane & Able Health Care Limited | Wholesale & retail | 1999 |
| Cane BUT Able Ltd. | Information & communication | 2010 |
| Canefield Confectionary Limited | Manufacturing | 2014 |
| Canela Studio Limited | Professional & scientific | 2023 |
| Canham Consulting Ltd | Construction | 1992 |
| Canham Engineering Limited | Professional & scientific | 2025 |
| Canine Comps Ltd | Wholesale & retail | 2025 |
| Canine DIP and Dive Wymondham Ltd | Administrative & support | 2023 |
| Canine Snip and DRY Ltd | Wholesale & retail | 2026 |
| Canis Properties Limited | Hospitality | 2019 |
| Cann Electrical Services Ltd | Construction | 2025 |
| Cann Secure Limited | Other services | 2016 |
| Canning Electrical Limited | Construction | 2003 |
| Cannon Clarke Architects Ltd | Professional & scientific | 2015 |
| Canran Technology/Investments (UK) Limited | Extraterritorial | 2000 |
| Cantefield Ltd | Arts & recreation | 2012 |
| Cantium Energy Limited | Energy | 2008 |
| Cantley Cock Limited | Hospitality | 2020 |
| Canton East Anglia Ltd | Hospitality | 2024 |
| Canton Norwich Ltd | Hospitality | 2025 |
| Canvas Tattoo Co Ltd | Manufacturing | 2023 |
| Canvey Island Seafood Company Ltd | Wholesale & retail | 2021 |
| Canvey Pilah Holdings Ltd | Financial services | 2025 |
| CAP SIM Holdings Limited | Real estate | 2023 |
| CAP Trac Holdings Ltd | Financial services | 2022 |
| CAP Trac Ltd | Construction | 2009 |
| CAP Trac Sales Ltd | Wholesale & retail | 2022 |
| Capacity Cloud Ltd | Information & communication | 2019 |
| Capacity Research Limited | Administrative & support | 2011 |
| Capcir Consulting Limited | Other services | 2019 |
| Cape Care Ltd | Health & social care | 2025 |
| Cape Renovations Ltd | Construction | 2022 |
| Capel Planning Limited | Professional & scientific | 2012 |
| Capitac Holdings Ltd | Financial services | 2024 |
| Capital & Growth Limited | Administrative & support | 2004 |
| Capital Business Technology Limited | Information & communication | 2018 |
| Capital Circuits Ltd | Manufacturing | 2018 |
| Capital Culture Gallery Ltd | Wholesale & retail | 2012 |
| Capital Energy Brokers Ltd | Administrative & support | 2018 |
| Capital Funding Aggregations Ltd | Other services | 2018 |
| Capital Recruitment London Ltd | Administrative & support | 2020 |
| Capka Holdings Limited | Real estate | 2023 |
| Capoeira Communities Limited | Education | 2006 |
| Capon Consulting Limited | Professional & scientific | 2006 |
| Caps Property Ltd | Administrative & support | 2011 |
| Capshot Ltd | Manufacturing | 2026 |
| Capvian Ltd | Financial services | 2026 |
| Car Dealer Media Ltd | Administrative & support | 2017 |
| Car OR Van Ltd | Wholesale & retail | 2011 |
| Car Park Investments Limited | Financial services | 1994 |
| Car Profiler Limited | Extraterritorial | 2016 |
| Car Shed Ltd | Wholesale & retail | 2020 |
| Car Station Suffolk Ltd | Wholesale & retail | 2024 |
| Car Torque UK Ltd | Wholesale & retail | 2025 |
| Car Valeting Norwich Ltd | Administrative & support | 2024 |
| Caracol Books Ltd | Wholesale & retail | 2023 |
| Caradon Healthcare Ltd | Health & social care | 2021 |
| Caranday Electrics Limited | Energy | 2011 |
| Caranx Limited | Other services | 2017 |
| Carapace Wealth Management Ltd | Professional & scientific | 2024 |
| Caraparts (Wroxham) Limited | Manufacturing | 2025 |
| Caravan Storage (Norwich) Ltd | Administrative & support | 2020 |
| Carberrys Cafe Ltd. | Hospitality | 2014 |
| Carbon Catcher Limited | Professional & scientific | 2021 |
| Carbon Connections UK Limited | Professional & scientific | 2006 |
| Carbon Saving Generation Limited | Energy | 2011 |
| Carbon Zero Services Ltd | Professional & scientific | 2020 |
| Carbonix Performance Ltd | Wholesale & retail | 2025 |
| Carbontrack UK Ltd | Professional & scientific | 2019 |
| Carbrooke Properties Ltd | Real estate | 2020 |
| Card Finds Ltd | Wholesale & retail | 2025 |
| Card O Rama Ltd | Wholesale & retail | 2025 |
| Cardi Cleaning Services Ltd | Administrative & support | 2023 |
| Cardiff Prestige Ltd | Wholesale & retail | 2017 |
| Cardington Court Residents' Association Limited | Households | 1989 |
| Cards 'N' Things Ltd | Wholesale & retail | 2011 |
| Care Apex Limited | Administrative & support | 2025 |
| Care Finder Assist Ltd | Information & communication | 2025 |
| Care for Children (UK) | Health & social care | 2005 |
| Care Guard 24/7 Ltd | Administrative & support | 2023 |
| Care Help UK Ltd | Construction | 2013 |
| Care Recruitment Ltd | Administrative & support | 2005 |
| Careers Without Frontiers Limited | Education | 2016 |
| Carefree Plan Ltd | Construction | 2024 |
| Carehub Ltd. | Health & social care | 2015 |
| Carelegend Ltd | Health & social care | 2022 |
| Carelift Services Limited | Other services | 2020 |
| Carenect Services Limited | Extraterritorial | 2024 |
| Carestaff Soloutions Ltd | Administrative & support | 2024 |
| Carestrat Consultancy Limited | Health & social care | 2025 |
| Caretemp Personnel Ltd | Administrative & support | 2018 |