| Cafe in the Park (Sutton) Ltd | Hospitality | 2017 |
| Cain Surfaces Ltd | Construction | 2019 |
| Cakemono Ltd | Manufacturing | 2024 |
| Calamity Jane Limited | Arts & recreation | 2014 |
| Calamity UK Tour Ltd | Arts & recreation | 2023 |
| Calderwell Limited | Real estate | 2000 |
| Caledonian Fire & Security Ltd | Professional & scientific | 2025 |
| Cali Healthcare Ltd | Health & social care | 2014 |
| Calisaysworkout Limited | Transport & logistics | 2018 |
| Caliyorkia Limited | Real estate | 2026 |
| Callaghan Demolition Limited | Construction | 1983 |
| Calleo Construction Limited | Construction | 2004 |
| Callum HS Limited | Wholesale & retail | 2017 |
| Calverstown Court Management Limited | Households | 1977 |
| Calyon Limited | Construction | 2026 |
| Cambio Healthcare Systems Limited | Information & communication | 2002 |
| Camborne House (Sutton) Limited | Households | 1962 |
| Cambridge CE Ltd | Education | 2024 |
| Cambridge Roofshield Ltd | Construction | 2025 |
| Cambridge Technology Limited | Professional & scientific | 2019 |
| Camden Road (Sutton) Management Limited | Households | 1978 |
| Cameo Prop Studio Limited | Administrative & support | 2025 |
| Camera Gear Ltd | Professional & scientific | 2025 |
| Camino Ltd | Information & communication | 2017 |
| Camperlove Ltd | Wholesale & retail | 2022 |
| Camrate Ltd | Information & communication | 2013 |
| Canadian Overseas Petroleum (UK) Limited | Mining & quarrying | 2009 |
| Canags Ltd | Administrative & support | 2023 |
| Cancer Awareness Trust Ltd | Health & social care | 2017 |
| Candezent Advisory Ltd | Professional & scientific | 2021 |
| Candia Consulting Limited | Professional & scientific | 2015 |
| Candy Consulting Ltd | Construction | 2024 |
| Canoodle Limited | Wholesale & retail | 2005 |
| Canopy Planning Services Limited | Real estate | 2001 |
| Cantaloupe (London) Limited | Professional & scientific | 2004 |
| Canvas IT UP Ltd | Wholesale & retail | 2014 |
| CAP Consultancy Limited | Extraterritorial | 2020 |
| Capital Car London Ltd | Wholesale & retail | 2019 |
| Capital Chinese Limited | Hospitality | 2024 |
| Capital GP Services Ltd | Extraterritorial | 2025 |
| Capital Leads Limited | Professional & scientific | 2024 |
| Capital Projects Management Ltd | Construction | 2012 |
| Capital Soundproofing Ltd | Construction | 2020 |
| Capitol Flooring Ltd | Construction | 2021 |
| Captai Solutions Limited | Information & communication | 2026 |
| Car Recovery Ltd | Extraterritorial | 2022 |
| Car Wash Surrey Ltd | Other services | 2025 |
| Cara International Consulting Limited | Administrative & support | 2006 |
| Carabella Consultancy Limited | Wholesale & retail | 2019 |
| CARBON13 Ltd | Wholesale & retail | 2023 |
| Carelli Court Freeholders Limited | Households | 2023 |
| Carenest Supported Living Ltd | Health & social care | 2026 |
| Caritas Candles Ltd | Wholesale & retail | 2024 |
| Carla Morris Accountancy Services Limited | Professional & scientific | 2016 |
| Carla's Curiosities Ltd | Arts & recreation | 2019 |
| Carlington House Limited | Households | 1999 |
| Carmona Restaurant Ltd | Hospitality | 2021 |
| Carole's Crêperie Ltd | Hospitality | 2018 |
| Carpatic Design Ltd | Wholesale & retail | 2025 |
| Carpatic Ltd | Wholesale & retail | 2024 |
| Carpet Village Limited | Wholesale & retail | 1983 |
| Carrick Construction Group Ltd | Construction | 2024 |
| Cars 4 U Trading Limited | Wholesale & retail | 2025 |
| Carshalton Building Services Limited | Construction | 2012 |
| Carshalton Italian Ltd | Hospitality | 2023 |
| Carshalton Mini CAB Limited | Transport & logistics | 2024 |
| Cartagena Consulting Ltd | Other services | 2018 |
| Cartique Ltd | Wholesale & retail | 2025 |
| Cartridge Online Limited | Wholesale & retail | 2022 |
| Carysium Consulting Limited | Professional & scientific | 2008 |
| Carzania Motor Group Limited | Wholesale & retail | 2023 |
| CAS Global Limited | Administrative & support | 2025 |
| CAS Lifts Limited | Construction | 2016 |
| Casca Civil Engineering Limited | Construction | 2017 |
| Casey's Consulting Ltd | Administrative & support | 2025 |
| Casmed International Limited | Wholesale & retail | 1996 |
| Cass Computing Ltd | Other services | 2019 |
| Castle Hill Foods Ltd | Hospitality | 2013 |
| Castleford Publishing Ltd | Wholesale & retail | 2020 |
| Castleton Close Limited | Households | 1990 |
| Casual Colours Ltd | Construction | 2014 |
| Catalyst AI Partners Ltd | Information & communication | 2025 |
| Catching Babies Ltd | Administrative & support | 2022 |
| Catering by the Green Ltd | Hospitality | 2022 |
| Cavco Limited | Extraterritorial | 1990 |
| CAY Logistics Ltd | Transport & logistics | 2026 |
| CBS Investments & Development Limited | Real estate | 2018 |
| CC & AA Holdings Ltd | Real estate | 2017 |
| CC Iwuoha & Partners Limited | Health & social care | 2025 |
| CC2I Limited | Information & communication | 2016 |
| Ccus Solutions Ltd | Professional & scientific | 2024 |
| CDC Construct Limited | Construction | 2023 |
| CDK Developments Limited | Wholesale & retail | 2003 |
| CDM Detailing Services Ltd | Professional & scientific | 2013 |
| Cebtec Limited | Wholesale & retail | 2009 |
| Cedar Building Services (London) Ltd | Construction | 2020 |
| Cedar Court (Sutton) Management Company Limited | Households | 1985 |
| Cedar Road Residents Co.Limited | Households | 1968 |
| Ceehoney Angel Cares Ltd | Information & communication | 2024 |
| Ceehoney Hub Ltd | Professional & scientific | 2024 |