| C G Installations Limited | Construction | 2007 |
| C G Mechanics Ltd | Wholesale & retail | 2023 |
| C H Telecommunications Service Ltd | Information & communication | 2014 |
| C Hodges Scaffolding Ltd | Construction | 2015 |
| C Khan Electrical & Mechanical Ltd | Construction | 2020 |
| C M & O2 Global Partners Limited | Health & social care | 2015 |
| C M Goldfinch Ltd | Construction | 2009 |
| C M Jack Building Services Limited | Construction | 2017 |
| C P D Sourcing Solutions Limited | Professional & scientific | 2017 |
| C W Construction Management Ltd | Professional & scientific | 2025 |
| C&C Capital Management Limited | Wholesale & retail | 2020 |
| C&E Contractors Ltd | Construction | 2025 |
| C&Hcare Ltd | Health & social care | 2013 |
| C&R Landlord Services Limited | Real estate | 2015 |
| C. Mcloughlin Property Ltd | Real estate | 2024 |
| C. R. Child and Partners Limited | Real estate | 2007 |
| C.A.L Property Services Ltd | Real estate | 2023 |
| C.E.Murch Limited | Agriculture & fishing | 1949 |
| C.F Access Solutions Ltd | Construction | 2025 |
| C.L.E.A.N. Commercial Cleaning Services Ltd | Administrative & support | 2014 |
| C.R. Child and Partners (New Homes) LLP | | 2014 |
| C.S.S. Environmental Limited | Other services | 2002 |
| C25 Furniture Limited | Manufacturing | 2020 |
| C73 Events Ltd | Arts & recreation | 2024 |
| CA Garden Services Ltd | Administrative & support | 2014 |
| CAB IT Kent Limited | Transport & logistics | 2023 |
| CAB Recruitment Service Ltd | Administrative & support | 2026 |
| Cabera Holdings Ltd | Financial services | 2025 |
| Cable Warehouse Limited | Wholesale & retail | 2019 |
| Cadi-M Ltd | Wholesale & retail | 2025 |
| Cakes by Raine Ltd | Manufacturing | 2022 |
| Calcone Limited | Construction | 2014 |
| Caledonian Capital Partners Limited | Professional & scientific | 2003 |
| Caledonian Publishing Limited | Professional & scientific | 2007 |
| Calisto Services Ltd | Public administration | 2025 |
| Call & Response Studios Ltd | Administrative & support | 2020 |
| Calm Family Services Ltd | Health & social care | 2024 |
| Calvary Blossoms Ltd | Administrative & support | 2019 |
| Calvary Medicare Services Ltd | Health & social care | 2010 |
| Calvary Medics Ltd | Health & social care | 2020 |
| Camam Limited | Real estate | 2025 |
| Camas Property Holdings Limited | Real estate | 2025 |
| Cambridge Tuition Centre Limited | Education | 2025 |
| Cameden Limited | Hospitality | 2016 |
| Camino Covent Garden Limited | Real estate | 2024 |
| Camino Farringdon Ltd | Real estate | 2024 |
| Camino Kings Cross Ltd | Real estate | 2020 |
| Camino Monument Ltd | Real estate | 2020 |
| Camino Shoreditch Ltd | Real estate | 2020 |
| Camino Trading Ltd | Hospitality | 2020 |
| Camino Victoria Limited | Real estate | 2025 |
| Camp David Property Limited | Real estate | 2022 |
| Campbell Electrical Kent Ltd | Construction | 2022 |
| Campbell Laser Cutters Limited | Manufacturing | 1999 |
| Canaan, Bethel & Shiloh (CBS) Care Ltd | Health & social care | 2025 |
| Candeur Ltd | Health & social care | 2020 |
| Candle Spa Limited | Manufacturing | 2014 |
| Candy Carriers Limited | Transport & logistics | 2003 |
| Candy Shisha Ltd | Wholesale & retail | 2024 |
| Cantaloupe Group Limited | Financial services | 2001 |
| CAO Services Limited | Health & social care | 2016 |
| Capable Cleaners Ltd | Other services | 2015 |
| Capellas Ltd | Education | 2007 |
| Capijo Ltd | Transport & logistics | 2022 |
| Capital Contracts Inc Ltd | Construction | 2013 |
| Capital Edge Management Ltd | Financial services | 2024 |
| Capitaledge Co Ltd | Information & communication | 2023 |
| Caplin Moore Ltd | Information & communication | 2026 |
| Capp Limited | Other services | 1995 |
| Captol UK Limited | Other services | 2018 |
| Car City Kent Ltd | Wholesale & retail | 2014 |
| Car City Medway Ltd | Wholesale & retail | 2021 |
| Carbis Loadtec Group Limited | Wholesale & retail | 2019 |
| Carbon Stone Estates Ltd | Real estate | 2026 |
| Cardinal Clicks Ltd | Information & communication | 2024 |
| Care Cash C.I.C. | Financial services | 2019 |
| Careassured Home Limited | Hospitality | 2023 |
| Career Masterclass Ltd | Education | 2015 |
| Career Smart Limited | Administrative & support | 2016 |
| Careprof Limited | Health & social care | 2019 |
| Careproof Ltd | Information & communication | 2026 |
| Careshore Limited | Health & social care | 2022 |
| Cargo Connect Solutions Ltd | Transport & logistics | 2025 |
| Caring Hands and Nursing Services Limited | Other services | 2019 |
| Carleys Inheritance Services Limited | Administrative & support | 2009 |
| Carleys Integrated Solutions Limited | Administrative & support | 2007 |
| Carleys Limited | Extraterritorial | 2024 |
| Carlos Rodrigues Limited | Health & social care | 2026 |
| Carmichael Education Limited | Education | 2005 |
| Carncat Ltd | Wholesale & retail | 2026 |
| Caroline Connor & Associates Limited | Administrative & support | 2003 |
| Caroline Mcateer Ltd | Other services | 2006 |
| Carolinetabiti Atelier Ltd | Manufacturing | 2025 |
| Carpentry Estimator Ltd | Professional & scientific | 2020 |
| Carpet Cleaning Medway Ltd | Administrative & support | 2026 |
| Carrington Homes Limited | Construction | 1996 |
| Carter Home & Security Maintenance Limited | Administrative & support | 2019 |
| Carters Valeting of Henwood Limited | Administrative & support | 2014 |
| Casa DI Dolce Limited | Real estate | 2024 |
| Casas Rentals UK Ltd | Real estate | 2018 |