| Carter Bench Management Company Limited | Households | 2003 |
| Carter Groves Estate Agents Ltd | Real estate | 2022 |
| Carthaginian Limited | Professional & scientific | 2018 |
| Cartlan Limited | Information & communication | 2003 |
| Cartwright Tree Care Limited | Administrative & support | 2026 |
| Carvline Ltd | Professional & scientific | 2026 |
| Carygen Limited | Administrative & support | 2014 |
| Casa Argentina Limited | Wholesale & retail | 2019 |
| Casa Linda Renovations Limited | Construction | 2023 |
| Casa Properties & Lets Ltd | Real estate | 2019 |
| Casablanca Phone Limited | Wholesale & retail | 2019 |
| Casamea Ltd | Real estate | 2020 |
| Cascade Trading Group Ltd | Education | 2024 |
| Case & Young Limited | Construction | 2015 |
| Caspian House Limited | Administrative & support | 2012 |
| Cassidy Commissioning Services Limited | Administrative & support | 2007 |
| Cassons Financial Planning Limited | Financial services | 2012 |
| Cassowary Strategy Ltd | Professional & scientific | 2022 |
| Castalloy Europe Limited | Manufacturing | 2016 |
| Castle Hvac Limited | Other services | 2013 |
| Castlefield Project Management Ltd | Construction | 2013 |
| Castlemere Properties Limited | Real estate | 1994 |
| Castleoak Care Developments Limited | Construction | 2006 |
| Castleoak Construction Limited | Professional & scientific | 2005 |
| Castleoak Holdings Limited | Professional & scientific | 2001 |
| Castletarf Ltd | Real estate | 2024 |
| Caswell Developments Ltd | Construction | 2026 |
| Catalio Capital UK Ltd. | Financial services | 2021 |
| Catalyst Training Solutions Limited | Professional & scientific | 2023 |
| Catalyte Investments LLP | | 2026 |
| Catch Fishmonger Limited | Wholesale & retail | 2022 |
| Catering Equipment Sales Limited | Wholesale & retail | 2007 |
| Catering MEN Ltd | Hospitality | 2025 |
| Cato Capital Ltd | Professional & scientific | 2026 |
| Cato Development Ltd | Construction | 2020 |
| Cato Graylaw Ltd | Real estate | 2023 |
| Cato One Ltd | Real estate | 2019 |
| Catology Consulting Limited | Professional & scientific | 2018 |
| Catsu Property Ltd | Real estate | 2025 |
| Cavendish (Stroud) Limited | Financial services | 2017 |
| Cavendish Bowdon Management Limited | Real estate | 2014 |
| Cavendish Care (Stroud) Limited | Health & social care | 2017 |
| Cavendish Care Home Limited | Health & social care | 2003 |
| Cavendish Mews Management Company (Wilmslow) Limited | Households | 1983 |
| Cavitech Solutions (Holdings) Limited | Professional & scientific | 2016 |
| Cavitech Solutions Limited | Manufacturing | 1990 |
| CAW Developments Ltd | Real estate | 2025 |
| CAW Investments Ltd | Construction | 2024 |
| CAW Property Ltd | Real estate | 2022 |
| CAW Technical Solutions Ltd | Information & communication | 2018 |
| Cawigo Group Limited | Professional & scientific | 2020 |
| CAY Care Limited | Professional & scientific | 2022 |
| Cazzumptions Limited | Information & communication | 2018 |
| CB Dental Care Ltd | Health & social care | 2022 |
| CB Hairdressing Limited | Other services | 2010 |
| CBD Access Limited | Manufacturing | 2018 |
| CBS T/As Car Body Solutions Ltd | Wholesale & retail | 2011 |
| Cbtm Ltd | Wholesale & retail | 2026 |
| CBV Psychiatry Ltd | Health & social care | 2025 |
| CC Childcare Ltd | Health & social care | 2017 |
| CC Nursery Ltd | Health & social care | 2021 |
| CCD Securities Limited | Construction | 2000 |
| CCIE9139 Limited | Professional & scientific | 2023 |
| CCL Aviation (UK) Limited | Transport & logistics | 2014 |
| CCM Regulatory Consultancy Ltd | Professional & scientific | 2013 |
| CD99 Life Sciences Ltd | Administrative & support | 2024 |
| CDG Emerald Limited | Professional & scientific | 2007 |
| CDH Collective CIC | Education | 2026 |
| CDH Security Ltd | Administrative & support | 2022 |
| CDL Consultants Limited | Energy | 2022 |
| CDP Infrastructure Design & Management Services Ltd | Professional & scientific | 2013 |
| CDS Aviation Finishers Limited | Professional & scientific | 2024 |
| CE Advisory Limited | Financial services | 2022 |
| CE Strategic Consulting Limited | Professional & scientific | 2020 |
| CEA Holdings Limited | Professional & scientific | 1989 |
| Ceciss Limited | Real estate | 2017 |
| Cecoll Consulting Ltd | Professional & scientific | 2018 |
| Cedabond Catering Equipment Limited | Hospitality | 1977 |
| Cedar Avenue Management Limited | Households | 1984 |
| Cedar Solutions (Management) Limited | Professional & scientific | 2002 |
| Cedar Square (Alderley Park) Management Company Limited | Real estate | 2017 |
| Cedarrock Limited | Real estate | 2013 |
| Cedars (Heaton Moor) Management Company Limited(The) | Households | 1982 |
| Ceetec Solutions Limited | Information & communication | 2000 |
| Cegid Limited | Administrative & support | 2008 |
| Cegway Limited | Manufacturing | 2003 |
| Celerita Labs Ltd. | Information & communication | 2025 |
| Cellpath Holdings Limited | Professional & scientific | 2002 |
| Cellpath Limited | Manufacturing | 1984 |
| Celtic Star Limited | Wholesale & retail | 2023 |
| Cempa Capital 2 Limited | Financial services | 2023 |
| Cempa Capital Limited | Financial services | 2023 |
| Cenah Limited | Professional & scientific | 2018 |
| Cend International Limited | Wholesale & retail | 2013 |
| Cend Limited | Wholesale & retail | 2000 |
| Centessa Pharmaceuticals (UK) Limited | Professional & scientific | 2020 |
| Centessa Pharmaceuticals PLC | Professional & scientific | 2020 |
| Centioit Ltd | Real estate | 2020 |
| Central Coast Consulting Limited | Professional & scientific | 2023 |
| Central Hall Property SPV Ltd | Hospitality | 2026 |