| Capital Stays PVT Ltd | Real estate | 2023 |
| Capital Tuning Ltd | Information & communication | 2022 |
| Capital Ventures Europe Limited | Other services | 2018 |
| Capitalfireflood Limited | Administrative & support | 2026 |
| Capitax Limited | Professional & scientific | 2025 |
| Capitech Data Services Limited | Information & communication | 1994 |
| Capitis Advisors Ltd | Financial services | 2020 |
| Capitise Ltd | Financial services | 2025 |
| Capitize Ltd | Financial services | 2025 |
| Capitol Medicare Limited | Health & social care | 2018 |
| Capricorn Consultancy Ltd | Professional & scientific | 2026 |
| Capson Consultancy Ltd | Information & communication | 2022 |
| Capstone (DBT) Limited | Construction | 1998 |
| Capsule Properties Limited | Real estate | 2024 |
| Capswood Business Park Limited | Real estate | 2024 |
| Captain Baby Limited | Other services | 2022 |
| Captain Bijouplanet Ltd | Water & waste | 2025 |
| Captive Creation Limited | Manufacturing | 2007 |
| Capture Value Ltd | Information & communication | 2024 |
| Car 4 U Ltd | Wholesale & retail | 2011 |
| Car Audio 4 Less (UK) Limited | Wholesale & retail | 2009 |
| Car Care (UK) Limited | Wholesale & retail | 2014 |
| Car Club Nationwide Limited | Other services | 2018 |
| Car Collective Studios Ltd | Manufacturing | 2023 |
| Car Farm Ltd | Wholesale & retail | 2022 |
| Car Gallery Limited | Wholesale & retail | 2018 |
| Car Hire Experts Limited | Administrative & support | 2019 |
| Car LOT Harrow Limited | Wholesale & retail | 2018 |
| Car Marketing UK Limited | Professional & scientific | 2014 |
| Car Pinnacle UK Ltd | Wholesale & retail | 2023 |
| Cara Furniture Services Ltd | Wholesale & retail | 2020 |
| Cara Stationery and Office Supplies Ltd | Administrative & support | 1994 |
| Carambola Limited | Administrative & support | 2021 |
| Caramel London Ltd | Wholesale & retail | 2019 |
| Caramelo Latin Dance Academy Ltd | Education | 2013 |
| Caravia Ltd | Wholesale & retail | 2026 |
| Carbon Brief Ltd | Information & communication | 2010 |
| Carbon Core Limited | Professional & scientific | 2025 |
| Carbon Efficiency Contractors Ltd | Other services | 2011 |
| Carbon Global Ltd | Information & communication | 2017 |
| Carbon Theory Limited | Wholesale & retail | 2017 |
| Carbonstone UK Ltd | Wholesale & retail | 2025 |
| Carcea Ltd | Construction | 2013 |
| Cardano Blockchain Funding Services Ltd | Information & communication | 2018 |
| Cardano Blockchain Ltd | Information & communication | 2020 |
| Carden Road Management Company Limited | Extraterritorial | 2007 |
| Cardiac AP Ltd | Health & social care | 2019 |
| Cardio Connect Ltd | Health & social care | 2023 |
| Cardio Plus Ltd | Health & social care | 2022 |
| Cardiology Ltd | Health & social care | 2017 |
| Cardiomedical Ltd | Health & social care | 2026 |
| Cards Infinity Ltd | Wholesale & retail | 2023 |
| Care 2 Share 2 Ltd | Health & social care | 2005 |
| Care 2 Share Limited | Health & social care | 2002 |
| Care Accommodation (London) Limited | Construction | 2006 |
| Care Assist Limited | Health & social care | 2006 |
| Care Bloom Limited | Health & social care | 2024 |
| Care Clinic Limited | Administrative & support | 2022 |
| Care Compassion Limited | Health & social care | 2014 |
| Care for Youth Ltd | Arts & recreation | 2020 |
| Care Force Holdings (Domiciliary Care) Limited | Professional & scientific | 2010 |
| Care Force Limited | Health & social care | 1993 |
| Care Infinity Services Limited | Health & social care | 2016 |
| Care Platform Limited | Health & social care | 2021 |
| Care Practice Implementation Ltd | Education | 2026 |
| Care to Listen | Health & social care | 2008 |
| Care to Listen School of Counselling Limited | Education | 2024 |
| Care Trading Ltd | Wholesale & retail | 2024 |
| Care Venture Holdings Ltd | Health & social care | 2022 |
| CARE4OCUS Ltd | Health & social care | 2017 |
| Carebridge (UK) Limited | Health & social care | 2021 |
| Caredra Ltd | Professional & scientific | 2026 |
| Career Group Courses Limited | Education | 2017 |
| Careers in Design (Recruitment) Limited | Administrative & support | 2000 |
| Careers in Search Limited | Administrative & support | 2019 |
| Careflow Limited | Real estate | 2009 |
| Careland London Limited | Health & social care | 2021 |
| Carenest Yield Limited | Real estate | 2025 |
| Carepharm Limited | Professional & scientific | 2022 |
| Carepoint PCN Limited | Health & social care | 2023 |
| Carers for YOU Limited | Health & social care | 2008 |
| Cares Cleaning Services Ltd | Administrative & support | 2003 |
| Carestoisa Limited | Financial services | 2025 |
| Carewithloveco Ltd | Administrative & support | 2021 |
| Carey Commercial Repairs Limited | Wholesale & retail | 2010 |
| Carezon Ltd | Wholesale & retail | 2020 |
| Carformation Ltd | Wholesale & retail | 2021 |
| Carfound Limited | Wholesale & retail | 2023 |
| Cargo Commercial Ltd | Transport & logistics | 2015 |
| Cargo Imperial Food Limited | Wholesale & retail | 2015 |
| Cari Consultancy Limited | Information & communication | 2018 |
| Caribbean Twist Foods Ltd | Hospitality | 2024 |
| Carillon Music Services Ltd. | Arts & recreation | 2013 |
| Caring Crew Limited | Health & social care | 2018 |
| Caringa Ltd | Other services | 2017 |
| Caris Medical Ltd | Health & social care | 2022 |
| Caris Properties Limited | Construction | 2013 |
| Carl Robertshaw Design Ltd | Professional & scientific | 2021 |
| Carl Speed Box Ltd | Transport & logistics | 2025 |
| Carlos Fast Food Ltd | Hospitality | 2025 |