| Capture IT Limited | Information & communication | 1998 |
| Car Chase Motors Limited | Transport & logistics | 2022 |
| Car Sales Cranford Limited | Wholesale & retail | 2025 |
| Car Trade Centre Limited | Wholesale & retail | 2017 |
| Carade Limited | Other services | 2021 |
| Card Kingdom Limited | Wholesale & retail | 2021 |
| Cardigan Security Limited | Administrative & support | 2018 |
| Care Fine Ltd | Health & social care | 2025 |
| Care for Change Limited | Public administration | 2023 |
| Care Free Real Estate Investments Ltd | Real estate | 2019 |
| Care Global Ltd | Administrative & support | 2019 |
| Care O'Clock Agency Ltd | Health & social care | 2025 |
| Care Plus More Housing Ltd | Real estate | 2024 |
| Care Plus More Ltd | Health & social care | 2017 |
| Cared Choice Ltd | Professional & scientific | 2022 |
| Career Arena Ltd | Administrative & support | 2025 |
| Careplus Residential Services LP | | 2013 |
| Carers 4 YOU London Limited | Administrative & support | 2025 |
| Carflex Ltd | Wholesale & retail | 2020 |
| Cargavana Ltd | Wholesale & retail | 2025 |
| Cargo Liners Ltd | Construction | 2025 |
| Cargo Master Limited | Transport & logistics | 2025 |
| Cargo Tracking Ltd | Transport & logistics | 2019 |
| Carlos Gardening Services Limited | Administrative & support | 2020 |
| Carltons Property Services Limited | Real estate | 2008 |
| Carltons Residential Sales & Lettings Limited | Real estate | 2007 |
| Carnet Wizard Limited | Transport & logistics | 2024 |
| Carol Redman Ltd | Professional & scientific | 2022 |
| Caropoly Ltd | Wholesale & retail | 2021 |
| Carpet Boss Ltd | Construction | 2024 |
| Carpetime Limited | Construction | 2023 |
| Carringtons Limited | Professional & scientific | 1994 |
| Carringtons Upper Limited | Financial services | 2025 |
| Carrs Invest Freehold Limited | Real estate | 2025 |
| Carrs Invest Limited | Real estate | 2024 |
| Cars Choice Limited | Wholesale & retail | 2012 |
| Cars of Hanworth Village Ltd | Wholesale & retail | 2025 |
| Cartcraze Ltd | Wholesale & retail | 2025 |
| Cartify Ltd | Wholesale & retail | 2025 |
| Carver Estate LLP | | 2024 |
| Casa Amore Estates Limited | Real estate | 2018 |
| Casa Crunchy Limited | Hospitality | 2025 |
| Casa DE GOA Caterers Ltd | Hospitality | 2022 |
| Casa DE GOA Limited | Hospitality | 2015 |
| Casa DE Moçambique United Kingdom Community Interest Company | Other services | 2021 |
| Cascades Consulting and Advisors Ltd | Information & communication | 2024 |
| Case 1 Vehicle 1 Limited | Professional & scientific | 2026 |
| Case Collection Ltd | Wholesale & retail | 2014 |
| Castle Rising Dental Suite Ltd | Health & social care | 2023 |
| Catalyst Human Resource Solutions Limited | Administrative & support | 2025 |
| Catalyticverbs Ltd | Professional & scientific | 2023 |
| Catch a Minicab Ltd | Transport & logistics | 2018 |
| Caterize Limited | Hospitality | 2021 |
| Catherine Homecare Ltd | Administrative & support | 2016 |
| Cavendish Logistics Services Limited | Transport & logistics | 2026 |
| Caversham Food and Wine Limited | Wholesale & retail | 2012 |
| CB Environmental Solutions Limited | Construction | 2022 |
| Cbaov Limited | Information & communication | 2018 |
| CBK Freight Limited | Transport & logistics | 2018 |
| CBS Consulting Services Ltd | Information & communication | 2016 |
| CBS Employment Ltd | Administrative & support | 2020 |
| Cbtfm Limited | Wholesale & retail | 2022 |
| CBZ Alin Ltd | Transport & logistics | 2025 |
| Ccbs Services Ltd | Construction | 2019 |
| Ccclxv Limited | Professional & scientific | 2023 |
| Ccha Limited | Manufacturing | 2019 |
| CD Security Systems & Fire Ltd | Administrative & support | 2022 |
| CD Trade Ltd | Administrative & support | 2020 |
| Ceceblu Ltd | Wholesale & retail | 2024 |
| Cedar Cusine Limited | Hospitality | 2023 |
| Cedar Link International Limited | Extraterritorial | 1984 |
| Ceiling Partition Specialists Ltd | Construction | 2017 |
| Celebbars Limited | Hospitality | 2022 |
| Celebration Events 1 Ltd | Information & communication | 2019 |
| Celebration Treats Ltd | Administrative & support | 2020 |
| Celebrity Soccer Ltd | Arts & recreation | 2025 |
| Celestia Magazine Ltd | Information & communication | 2020 |
| Cell Crazy Limited | Wholesale & retail | 2021 |
| Cell N Tell Limited | Information & communication | 2026 |
| Cell Tech Repairs Oxford Limited | Other services | 2026 |
| Celltech Limited | Other services | 2019 |
| Centauri Security Limited | Real estate | 2022 |
| Centeno.Art Ltd | Arts & recreation | 2020 |
| Central Barbers Hounslow Ltd | Other services | 2025 |
| Central Convenience Ltd | Wholesale & retail | 2024 |
| Central Drive (Blackpool) Management Limited | Hospitality | 2005 |
| Central Enconomy Stores Limited | Wholesale & retail | 2017 |
| Centre for Smart Health Research & Innovation UK Limited | Health & social care | 2023 |
| Centre for UK Education & Recruitment Ltd | Administrative & support | 2014 |
| Centre of Professional Studies Limited | Professional & scientific | 2019 |
| Certus Accounts Ltd | Professional & scientific | 2021 |
| Cestrensis Limited | Real estate | 2025 |
| CF Construction London Ltd | Construction | 2025 |
| CFC (London) Limited | Hospitality | 2024 |
| CFP Complete Home Services Ltd | Construction | 2026 |
| CH4 GAS Training Services Limited | Education | 2006 |
| CHA SHA Hounslow Ltd | Hospitality | 2022 |
| Chaahat Superstore Ltd | Wholesale & retail | 2025 |
| Chaapy Ltd | Information & communication | 2026 |
| Chaarm Productions Limited | Information & communication | 2013 |