| Cancan Properties Limited | Real estate | 2025 |
| Cancan Studios Limited | Information & communication | 2025 |
| Candyhouseuk Limited | Wholesale & retail | 2025 |
| Canett Ltd | Education | 2026 |
| Canton Flavour Limited | Hospitality | 1997 |
| CAP Advice Ltd | Professional & scientific | 2026 |
| CAP Excavations Limited | Construction | 2019 |
| CAP Liners Limited | Manufacturing | 1966 |
| Capak Ltd | Administrative & support | 2009 |
| Capewater Properties Limited | Construction | 2001 |
| Capital Equipment Buying Solutions Ltd | Wholesale & retail | 2013 |
| Capricorn Corporation Ltd | Wholesale & retail | 2012 |
| Capwine Limited | | 1984 |
| Car & Commercial Vehicle Dismantlers Limited | Water & waste | 2013 |
| Car Commerce Ltd | Wholesale & retail | 2019 |
| Car Park Burnsall Ltd | Real estate | 2017 |
| Car Play 247 Ltd | Wholesale & retail | 2019 |
| Car Rave Ltd | Wholesale & retail | 2023 |
| Car Trade Specialists Ltd | Wholesale & retail | 2024 |
| Cara Haulage Limited | Transport & logistics | 2017 |
| Caravan Guard Limited | Financial services | 2000 |
| Carbon Auto Styling Limited | Wholesale & retail | 2025 |
| Carbon Build Limited | Professional & scientific | 2025 |
| Cardiology Manchester Ltd | Health & social care | 2019 |
| Care Cabin Health Ltd | Health & social care | 2024 |
| Care Thai Therapy Ltd | Health & social care | 2021 |
| Care Within Ltd | Health & social care | 2018 |
| Care Withus Ltd | Hospitality | 2026 |
| Carefreerental Ltd | Real estate | 2024 |
| Cargo Pilot Ltd | Transport & logistics | 2026 |
| Caribopps Ltd | Information & communication | 2024 |
| Caring for Health Limited | Health & social care | 2013 |
| Caritas Unwanted Limited Partnership | | 2019 |
| Carl Kearney Limited | Manufacturing | 2016 |
| Carla Castillo Digital Limited | Information & communication | 2024 |
| Carland Empire Ltd | Wholesale & retail | 2023 |
| Carlito Properties Limited | Real estate | 2021 |
| Carmech Automotive Limited | Wholesale & retail | 2021 |
| Carnsew Developments Limited | Construction | 2018 |
| Carology HX Ltd | Wholesale & retail | 2026 |
| Carolyn Cedars Ltd | Wholesale & retail | 2024 |
| CARPARTS123 Limited | Wholesale & retail | 2016 |
| Carpets Like a Boss!!!! CIC | Wholesale & retail | 2025 |
| Carpi Designs Limited | Wholesale & retail | 2026 |
| Carpizo Motors Ltd | Wholesale & retail | 2020 |
| Carrick Medical Services Ltd | Health & social care | 2020 |
| Carrie Mckenzie Limited | Wholesale & retail | 2012 |
| Carroll Computing Limited | Information & communication | 2014 |
| Cars&Co (HX) Limited | Wholesale & retail | 2021 |
| Carter Mcbride Limited | Transport & logistics | 2021 |
| Carter Property Maintenance Ltd | Construction | 2024 |
| Carter Retail Ltd | Manufacturing | 2022 |
| Casa Pizza Halifax Ltd | Hospitality | 2019 |
| Casaconca Ltd | Professional & scientific | 2024 |
| Cascaldion Networks Ltd | Wholesale & retail | 2025 |
| Cash Converters Lancashire Limited | Wholesale & retail | 2003 |
| Cash Converters Yorkshire Limited | Wholesale & retail | 2007 |
| CASH4ANYCARS Ltd | Other services | 2020 |
| Cashmerecheck Limited | Professional & scientific | 2011 |
| Casius Limited | Extraterritorial | 1998 |
| Cass Computers Limited | Information & communication | 2019 |
| Cast Iron UK Limited | Wholesale & retail | 2021 |
| Castle Homes (Yorkshire) Limited | Construction | 1975 |
| Castle Sanders Ltd | Wholesale & retail | 2024 |
| Castle Villas Limited | Real estate | 2000 |
| Castlefield Beauty Bar Ltd | Other services | 2015 |
| Castmark Limited | Hospitality | 1994 |
| Casual Living Ltd | Households | 2024 |
| Cat VII Limited | Real estate | 2014 |
| Catapult Property Group Ltd | Real estate | 2025 |
| Catering and Laundry Servicing Ltd | Administrative & support | 2019 |
| Catering Business Management Ltd | Hospitality | 2013 |
| Catering Facilities Ltd | Hospitality | 2024 |
| Catering Lite Limited | Wholesale & retail | 2025 |
| Catom Supply Ltd | Wholesale & retail | 2023 |
| Catzy Ltd | Wholesale & retail | 2022 |
| Cavalier Country Club Limited | Hospitality | 1962 |
| Cave Architecture Ltd | Professional & scientific | 2014 |
| Cavendish Verge Ltd | Wholesale & retail | 2025 |
| Cawdron Holdings Ltd | Financial services | 2018 |
| Cawdry Associates Limited | Professional & scientific | 2018 |
| Cawood Therapy Services Ltd | Health & social care | 2024 |
| Caxton Agency Limited | Wholesale & retail | 2015 |
| Caz's Pooches Ltd | Agriculture & fishing | 2020 |
| CB Landscapes Limited | Professional & scientific | 2017 |
| Cb&C Ltd | Wholesale & retail | 2021 |
| Ccfa Limited | Arts & recreation | 2025 |
| Ccrm Limited | Administrative & support | 2014 |
| CCS Pipework & Civil Engineering Limited | Professional & scientific | 2024 |
| CCY and CCL Properties Limited | Real estate | 2023 |
| Cdsm Properties Limited | Construction | 2020 |
| Cdti Ltd | Construction | 2021 |
| CE Brickwork Ltd | Construction | 2026 |
| Cece Blooms Ltd | Wholesale & retail | 2019 |
| CED Consultants Ltd | Other services | 2025 |
| Celebration of Life Ltd. | Wholesale & retail | 1995 |
| Celestial Partners Ltd | Wholesale & retail | 2025 |
| Cellbuddy Express Ltd | Wholesale & retail | 2024 |
| Celsius Consulting Limited | Professional & scientific | 2016 |
| Celtic Castles Limited | Administrative & support | 2003 |