| C D Anderson Hayes Limited | Real estate | 2015 |
| C D Anderson Inc Limited | Extraterritorial | 2015 |
| C D Anderson Lettings Limited | Real estate | 2025 |
| C Hear Technologies Ltd | Wholesale & retail | 2026 |
| C Holden Consulting Limited | Information & communication | 2012 |
| C I Patel and Sons Ltd | Construction | 2013 |
| C I R Custom Carpentry Limited | Construction | 2026 |
| C L M P Limited | Administrative & support | 2010 |
| C M Tang Enterprises Limited | Real estate | 2012 |
| C P Harrow Management Ltd | Real estate | 2023 |
| C POP Plumbing Ltd | Construction | 2021 |
| C S & O Limited | Other services | 2015 |
| C S Gallo Limited | Arts & recreation | 2024 |
| C S Law Solicitors Ltd | Professional & scientific | 2021 |
| C Sharman & Sons Limited | Construction | 2024 |
| C Smiles Ltd | Health & social care | 2024 |
| C&A Arhitectural Ltd | Construction | 2015 |
| C&B Scottfield Limited | Hospitality | 2018 |
| C&B Ventures Limited | Hospitality | 2018 |
| C&C Property Investment Holdings Ltd | Real estate | 2025 |
| C&C Property Rentals Limited | Real estate | 2025 |
| C&C Quality Ltd | Transport & logistics | 2023 |
| C&C Removals&Transport Ltd | Transport & logistics | 2026 |
| C&I Constructions UK Limited | Construction | 2018 |
| C&J Plumbing Ltd | Construction | 2023 |
| C&M Construct Ltd | Construction | 2019 |
| C&M General Construction Ltd | Construction | 2025 |
| C&M Hospitality Collection Ltd | Hospitality | 2024 |
| C&O Plasterboard Solutions Limited | Construction | 2019 |
| C&R Palmer Holdings Limited | Financial services | 2020 |
| C&T Construction Ltd | Construction | 2023 |
| C-Squared (England) Ltd | Real estate | 2026 |
| C. Coyle Builders Limited | | 1985 |
| C.A.T. Creation LLP | | 2015 |
| C.B. Market Limited | Wholesale & retail | 2023 |
| C.C.T. Logistics Limited | Transport & logistics | 1993 |
| C.E. Planning Limited | Administrative & support | 2017 |
| C.I.D Systems Limited | Administrative & support | 2018 |
| C.I.Dura Construction Ltd | Construction | 2018 |
| C.J.H. Property Investment Company Limited | Real estate | 2016 |
| C.M & Sons Property and Care Ltd | Hospitality | 2025 |
| C.P Souvenir Ltd | Wholesale & retail | 2026 |
| C.Ramon & Co.Limited | Professional & scientific | 1951 |
| C.T.A Group Ltd | Construction | 2022 |
| C2 MAX Limited | Real estate | 2024 |
| C2 Security Ltd | Administrative & support | 2024 |
| C21 NRI Ltd | Real estate | 2026 |
| C3 Services Ltd | Construction | 2024 |
| C4S Online Ltd | Education | 2021 |
| CA Courier Services Ltd | Transport & logistics | 2015 |
| Caav Properties Limited | Real estate | 2019 |
| Cabinet Artistry Ltd | Manufacturing | 2019 |
| Cabsfinder Ltd | Transport & logistics | 2024 |
| Cacherel Ltd | Arts & recreation | 2025 |
| Cacophony Museum Limited | Information & communication | 2025 |
| Cactus Hound Bar Limited | Hospitality | 2018 |
| Cactus Hound Limited | Real estate | 2017 |
| Cactus Property Investments Ltd | Real estate | 2021 |
| Cadco Investments Limited | Real estate | 2018 |
| Cade RD Ltd | Financial services | 2024 |
| Caden Investments Limited | Real estate | 2022 |
| Caden Properties Limited | Real estate | 2019 |
| Cadila Pharmaceuticals (UK) Ltd | Wholesale & retail | 2000 |
| Cadp Harrison Limited | Real estate | 2014 |
| CAE Tax Ltd | Transport & logistics | 2020 |
| Caelestis Domus Ltd | Real estate | 2025 |
| Caenothus Blue Limited | Real estate | 2024 |
| Caeruleo Consulting Limited | Information & communication | 2013 |
| Cafasso Developments Limited | Construction | 2022 |
| Cafe Ancona Limited | Hospitality | 2013 |
| Cafe Bianco Ltd | Hospitality | 2020 |
| Cafe Harrow Ltd | Construction | 2020 |
| Cafe Moon Ltd | Hospitality | 2024 |
| Cafe Topnourish Limited | Hospitality | 2026 |
| Cafeja Ltd | Hospitality | 2023 |
| Cafeto Limited | Wholesale & retail | 2023 |
| Caffe Pascucci UK Ltd | Wholesale & retail | 2014 |
| CAG Studios Ltd | Information & communication | 2018 |
| Cairblan Limited | Professional & scientific | 1969 |
| Cairnpark Properties (the Vale) Limited | Construction | 2010 |
| Cajvana Rendering&Plastering Ltd | Construction | 2022 |
| Cake and More UK Ltd | Wholesale & retail | 2021 |
| Cake Craft Company Limited | Wholesale & retail | 2025 |
| Cake Fairy Heaven Limited | Manufacturing | 2020 |
| Cake Rani Limited | Hospitality | 2016 |
| Cake Villa Limited | Hospitality | 2019 |
| Caker Street Limited | Manufacturing | 2023 |
| Cakes & Bakes Rayners Lane Limited | Wholesale & retail | 2022 |
| Cakes & Bakes Ruislip Manor Limited | Wholesale & retail | 2022 |
| Cakes Limited | Manufacturing | 2021 |
| Cakeyit Ltd | Manufacturing | 2026 |
| Calangate Investments and Finance Limited | Financial services | 1987 |
| Calario Ltd | Wholesale & retail | 2026 |
| Calcot Medical Services Ltd | Real estate | 2022 |
| Calderdale and Huddersfield Orthopaedic Partnership LLP | | 2015 |
| Caldicott Holdings Limited | Professional & scientific | 2021 |
| Caledonian Developments (Watford) Limited | Construction | 2017 |
| Caledonian Incorporated Limited | Real estate | 2016 |
| Calgreen Limited | Wholesale & retail | 1972 |
| Calicotree Ltd | Wholesale & retail | 2018 |