| Caramba Dream Limited | Northwich | 2023 |
| Caramelnailsstudio Ltd | London | 2025 |
| Carandsco Limited | Glasgow | 1981 |
| Carann Limited | London | 2026 |
| Caranova Aesthetics and Skin Limited | Leeds | 2025 |
| Caranx Limited | Norwich | 2017 |
| Caras Colours Ltd | Porth | 2024 |
| Caratess Events Ltd | London | 2026 |
| Caravaggio Design Limited | London | 1996 |
| Caravan Care Plan Ltd | Driffield | 2026 |
| Caravan Club Limited(The) | East Grinstead | 1959 |
| Caravan Club of Great Britain and IRELAND(1935)LIMITED(THE) | East Grinstead | 1935 |
| Caravan GAS & Boat Services Limited | Chichester | 2010 |
| Caravan GAS Services Ltd | Bridlington | 2008 |
| Caravan Hospital Limited | Cowbridge | 2024 |
| Caravan MAN (Western) Limited | Exeter | 2007 |
| Caravan Security Storage Limited | Malton | 1999 |
| Caravan Storage Ltd | North Shields | 2011 |
| Caravan Tech (Sales) Ltd. | Etchingham | 1997 |
| CARAVAN6 Ltd. | Epping | 2009 |
| Caravelli Hair Design Ltd | Leicester | 2018 |
| Caraz Limited | Northallerton | 2002 |
| Cara’S Canines Ltd | Chelmsford | 2020 |
| Carberry Build (UK) Limited | Basildon | 2006 |
| Carberry Road Residents Limited | London | 2011 |
| Carbeth Hutters Community Company | Glasgow | 2008 |
| Carbide Services Ltd | Old Swan | 1997 |
| Carbide Tooling Group Ltd | Leeds | 2014 |
| Carbine Club London Limited | Brentwood | 2013 |
| Carbis Club Limited | London | 2023 |
| Carblab Ltd | London | 2025 |
| Carbliss Ltd | Dagenham | 2025 |
| Carbocris Ltd | Guildford | 2024 |
| Carbokappa Ltd | London | 2026 |
| Carbon 14 Limited | Whitehills Business Park | 2010 |
| Carbon Accounting Alliance Ltd | Wallington | 2025 |
| Carbon Bike Repair Limited | Wokingham | 2014 |
| Carbon Blush Limited | Bolton | 2013 |
| Carbon Capital Limited | London | 2014 |
| Carbon Capture Limited | Wrexham | 2024 |
| Carbon Clinic Ltd | London | 2023 |
| Carbon Club Limited | Retford | 2007 |
| Carbon Coast Limited | Weymouth | 2019 |
| Carbon Cycle Solutions Ltd | Leighton Buzzard | 2020 |
| Carbon Efficiency Contractors Ltd | Harrow | 2011 |
| Carbon Enterprises Limited | Esher | 1984 |
| Carbon Evse Consultants Limited | Wallasey | 2014 |
| Carbon Financial Planning Limited | Newport | 2011 |
| Carbon Fitness Training CIC | Camborne | 2025 |
| Carbon Fusion Ltd | Peterborough | 1985 |
| Carbon Happy World Ltd | Liverpool | 2020 |
| Carbon Hill Limited | Welshpool | 2021 |
| Carbon Image Limited | Lancashire | 1997 |
| Carbon Kapture Ltd | Southampton | 2020 |
| Carbon Machine Limited | Blackwood | 2019 |
| Carbon Neutral Grants Ltd | Bradford | 2023 |
| Carbon Neutral Journeys Ltd | Coventry | 2020 |
| Carbon Offset Cornwall Limited | Penryn | 2021 |
| Carbon Offsets Limited | Henley-On-Thames | 2006 |
| Carbon Positive Motorsport Ltd | Leamington Spa | 2020 |
| Carbon Profile Limited | Milton Keynes | 2014 |
| Carbon Supermarket Ltd | London | 2024 |
| Carbon UK Holdings Ltd | London | 2023 |
| Carbon.Gc Limited | Exeter | 2007 |
| CARBON247 Limited | St. Asaph | 1983 |
| Carbonado Consultancy Limited | South Normanton | 2023 |
| Carbonbit Limited | Lytham St Annes | 2013 |
| Carboncreditnow.Com Ltd | Llandysul | 2021 |
| Carbone Zero Limited | London | 2023 |
| Carbonsustain Solutions Ltd | Manchester | 2023 |
| Carbopress Technology Ltd | London | 2012 |
| Carclew Woodland Burial Ltd | Perran-Ar-Worthal | 2026 |
| Carcosa Hair & Beauty Limited | Edinburgh | 2005 |
| Carcou Ltd | Gloucester | 2024 |
| CARCREDIT2GO.CO.UK Ltd | Portsmouth | 2016 |
| Card Galacticos Limited | Southend-On-Sea | 2025 |
| Card Payment Gateway Ltd | Romford | 2022 |
| Card Payments Made Easy Ltd | Wigston | 2024 |
| Carda Limited | Enfield | 2005 |
| Cardamom Cream Limited | Manchester | 2012 |
| Cardan Financial Group Limited | Worcester | 2020 |
| Cardarmar Services Limited | London | 2013 |
| Cardbridge Ltd | Sutton Coldfield | 2026 |
| Cardcash Limited | London | 1987 |
| Cardea Barbers Limited | Peterborough | 2020 |
| Carden and Sons Ltd | Leeds | 2021 |
| Carden Spaces Ltd | Aberdeen | 2025 |
| Cardesa Aesthetics International Ltd | Northampton | 2023 |
| Cardiff Aesthetic Clinic Ltd | Barry | 2025 |
| Cardiff Athletics | Cardiff | 2018 |
| Cardiff Barbershop Limited | Cardiff | 2017 |
| Cardiff Basketball Foundation CIC | Newport | 2025 |
| Cardiff Bay Nails and Beauty Ltd | Cardiff | 2025 |
| Cardiff Beauty Clinic Limited | Cardiff | 2016 |
| Cardiff Business Club Limited | Cardiff | 1956 |
| Cardiff Chimney Stacks Limited | Cardiff | 2020 |
| Cardiff City Ladies Football Club Trustees Ltd | Cardiff | 2023 |
| Cardiff City Phones Ltd | Cardiff | 2024 |
| Cardiff City Skin Doctor Ltd | Cardiff | 2019 |
| Cardiff Cleaning Company Limited | Cardiff | 2016 |