| Cossit Ltd | Wholesale & retail | 2025 |
| Cost Design Group Ltd | Transport & logistics | 2022 |
| Cost Savvy Service Ltd | Other services | 2024 |
| Costa Carpentry Ltd | Construction | 2026 |
| Costa Koval Construction Limited | Construction | 2014 |
| Costa Pubs Ltd | Hospitality | 2018 |
| Costica Bleajbu Ltd | Construction | 2021 |
| Costu 2019 Ltd | Construction | 2019 |
| Coswo Ltd | Wholesale & retail | 2026 |
| Cosy Mark Limited | Wholesale & retail | 2025 |
| Cosy Rooms (Ilford) Limited | Hospitality | 2024 |
| Cosymonkey Ltd | Wholesale & retail | 2024 |
| Cotangent Limited | Information & communication | 2017 |
| Cothm Global Ltd | Education | 2022 |
| Cottonclub London Limited | Wholesale & retail | 2024 |
| Cougar K9 Services Ltd | Administrative & support | 2018 |
| Coughtrey & SON Limited | Real estate | 1939 |
| Count 247 Ltd | Wholesale & retail | 2022 |
| Countrywide Developers Ltd | Construction | 2019 |
| Countrywide Paving Construction Limited | Administrative & support | 2008 |
| County Care Homes Limited | Health & social care | 2003 |
| County Woodford Ltd | Real estate | 2016 |
| Courier Route Planner Limited | Information & communication | 2023 |
| Courtland Group Ltd | Real estate | 2021 |
| Courtney Lodge Management Limited | Real estate | 1996 |
| Courtney Towers Management Company Limited | Households | 1996 |
| Couture Tailoring Manchester Ltd | Other services | 2016 |
| Cove Solutions Ltd | Professional & scientific | 2015 |
| Covent Garden Construction Limited | Construction | 2010 |
| Coventry 7 Ltd | Real estate | 2020 |
| Covered Buckles Limited | Manufacturing | 1994 |
| Cowaty Ltd | Wholesale & retail | 2025 |
| Cowries Logistics & Procurement Limited | Wholesale & retail | 2022 |
| Cowslip Road Developments Limited | Construction | 2021 |
| Coxley Meadows Management Company Limited | Real estate | 2010 |
| Cozee Homes UK Ltd | Wholesale & retail | 2023 |
| Cozy Homes Limited | Hospitality | 2019 |
| Cozyt Limited | Real estate | 2026 |
| Cozzywear Ltd | Wholesale & retail | 2025 |
| CP LIL Ltd | Construction | 2024 |
| CP Metal Works Limited | Construction | 2023 |
| Cpandya Properties Ltd | Real estate | 2022 |
| Cphunt Limited | Construction | 2025 |
| CPN Properties Ltd | Real estate | 2024 |
| CQC & Tender Experts Ltd | Professional & scientific | 2025 |
| Cqplanning and Property Services Limited | Extraterritorial | 2015 |
| CR Commerce Limited | Wholesale & retail | 2026 |
| Cr&L Construction Limited | Construction | 2022 |
| Crab and Lobster Restaurants Limited | Hospitality | 2019 |
| Cradlestone Limited | Professional & scientific | 2019 |
| Craft and Creations Limited | Wholesale & retail | 2019 |
| Craft Basket Limited | Wholesale & retail | 2011 |
| Craft Cleaning Ltd | Administrative & support | 2023 |
| Craft RUM Box Ltd | Wholesale & retail | 2019 |
| CRAFT21 Limited | Manufacturing | 2021 |
| Crafted Corner Limited | Wholesale & retail | 2024 |
| Craftedwooduk Ltd | Manufacturing | 2020 |
| Crafts Corner Ltd | Wholesale & retail | 2020 |
| Crafty Bitz Ltd | Wholesale & retail | 2022 |
| Crafty Woodpeckers Ltd | Manufacturing | 2020 |
| Craigen Properties Limited | Real estate | 2022 |
| Cranberry Property Limited | Real estate | 2012 |
| Cranbrook 249 Ltd | Real estate | 2026 |
| Cranbrook Basement Design & Construction Limited | Construction | 2015 |
| Cranbrook Basements and Interiors Limited | Construction | 2021 |
| Cranbrook Basements London Limited | Construction | 2008 |
| Cranbrook Castle Montessori Ltd | Education | 2013 |
| Cranbrook College Limited | Other services | 2019 |
| Cranbrook Dragon Limited | Hospitality | 2025 |
| Cranbrook Estate Agent Ltd | Real estate | 2022 |
| Cranbrook Home Extensions Limited | Construction | 2010 |
| Cranbrook House Properties Limited | Real estate | 2003 |
| Cranbrook Lettings Ltd | Real estate | 2017 |
| Cranbrook Lodge Ltd | Real estate | 2025 |
| Cranbrook One Ltd | Real estate | 2017 |
| Cranbrook School 1896 Limited | Construction | 2016 |
| Cranbrook Store Ltd | Wholesale & retail | 2025 |
| Cranbrook Two Ltd | Real estate | 2019 |
| Cranbrook VA Ltd | Hospitality | 2025 |
| Crane for Hire Ltd | Administrative & support | 2025 |
| Craneberry Loyns Limited | Information & communication | 2023 |
| Cranfield Court (Woodford Green) Limited | Real estate | 1965 |
| Cranford Hotel Limited | Hospitality | 2010 |
| Cranleigh Contracts Limited | Construction | 1998 |
| Cranley Developments Ltd | Real estate | 2024 |
| Cranston Tawny Limited | Other services | 2022 |
| Cranton Electrical Limited | Manufacturing | 2020 |
| Craoslach Construction Ltd | Construction | 2015 |
| Crapht Ltd | Other services | 2019 |
| Crave Cafe UK Ltd | Hospitality | 2020 |
| Crave London Ltd | Hospitality | 2020 |
| Crave Station Ltd | Hospitality | 2025 |
| Craw Interiors Ltd | Construction | 2024 |
| Crawford Bavent Limited | Other services | 2023 |
| Crawford Cafe Limited | Hospitality | 2020 |
| Craze Mode Ltd | Wholesale & retail | 2024 |
| Crazy Deals Ltd | Wholesale & retail | 2025 |
| Crazy Ginger Cabbie Promotions Ltd | Information & communication | 2025 |
| Crazy Horse Limited | Manufacturing | 1989 |
| Crazy Ice Cream Van Ltd | Wholesale & retail | 2024 |