| Crib Goch Ltd | Real estate | 2021 |
| Crimson Berry Ltd | Real estate | 2019 |
| Crimson KID Studios Ltd. | Professional & scientific | 2025 |
| Crisvir Ltd | Health & social care | 2018 |
| Critical Care Limited | Health & social care | 2006 |
| Crmdev Ltd | Information & communication | 2014 |
| Cromwell Consulting Ltd. | Professional & scientific | 2012 |
| Cronos Group Services Ltd | Administrative & support | 2024 |
| Cronos Protection Limited | Administrative & support | 2022 |
| Cross Development Ltd | Real estate | 2014 |
| Cross-Border E-Commerce Overseas Exhibition Center Ltd | Professional & scientific | 2022 |
| Crossness Residents Association (UK) RTM Company Limited | Administrative & support | 2009 |
| Crowntree Developments Limited | Construction | 2002 |
| Crowthorne Property Maintenance Limited | Construction | 1992 |
| Croydon Commercial Sales Limited | Wholesale & retail | 2013 |
| Crucial Projects Limited | Professional & scientific | 2012 |
| Cruel Summer Publishing Ltd | Information & communication | 2014 |
| Crushfreeze Limited | Professional & scientific | 2024 |
| Crusoe Bidco Limited | Financial services | 2018 |
| Crusoe EBT & Nominee Limited | Financial services | 2018 |
| Crusoe Midco Limited | Financial services | 2018 |
| Crusoe Topco Limited | Financial services | 2018 |
| Crust Group Limited | Hospitality | 2026 |
| Crwn Clothing Ltd | Wholesale & retail | 2021 |
| Cryptic Red Ltd | Information & communication | 2018 |
| Crystal Nails Epsom Limited | Other services | 2025 |
| Crystalgurad Double Glazing Ltd | Construction | 2021 |
| CS Flooring Contractors Limited | Construction | 2012 |
| CSA Solutions Ltd | Information & communication | 2015 |
| CSH Lighting Limited | Construction | 2022 |
| Csso Lewis Ltd | Hospitality | 2022 |
| CTG Electrical Limited | Construction | 2017 |
| CU Bridge Limited | Education | 2012 |
| Cuandor Roofing & Facades (CRF) Ltd | Construction | 2018 |
| Cubic Street Ltd | Professional & scientific | 2008 |
| Cubix Digital Ltd | Information & communication | 2020 |
| Cuddington Glade Management Limited | Real estate | 2010 |
| Cuddlecrafts Ltd | Manufacturing | 2024 |
| Cuescript Hire Limited | Administrative & support | 2013 |
| Cuescript Limited | Manufacturing | 2013 |
| Cuisine Collection Limited | Hospitality | 1998 |
| Cullen & Co UK Limited | Financial services | 2016 |
| Culture Shock Apps Ltd | Information & communication | 2025 |
| Cumbria Court (Reigate) Mangement Co. Limited | Households | 2003 |
| Cumbria Court 2009 (Reigate) RTM Limited | Professional & scientific | 2009 |
| Cumpsty Communications Ltd | Professional & scientific | 2012 |
| Cunliffe Close Headley Residents Association Limited | Households | 2022 |
| Cupello Limited | Arts & recreation | 2019 |
| Cupello Tech Ltd | Information & communication | 2021 |
| Curious Kids Limited | Education | 2022 |
| Curly Bakes Ltd | Wholesale & retail | 2025 |
| Curzon Homes Limited | Administrative & support | 2002 |
| Curzon Investment Partners Ltd | Financial services | 2020 |
| Customers Europe Limited | Extraterritorial | 2003 |
| Customers for Life Consulting Ltd | Professional & scientific | 2022 |
| Customers Global Limited | Extraterritorial | 2003 |
| Customers Limited | Professional & scientific | 2003 |
| Customised Homes Ltd | Construction | 2021 |
| Cuts Above Ltd | Other services | 2021 |
| Cutting Edge Records Limited | Information & communication | 2020 |
| CVJ Ltd | Wholesale & retail | 2025 |
| CW Building Solutions Limited | Construction | 2016 |
| CW Heating and Electrical Limited | Construction | 2023 |
| CW Yard Management Company Limited | Professional & scientific | 2013 |
| CWM Limited | Professional & scientific | 2011 |
| CWS Access Limited | Construction | 2023 |
| CWS Hub Limited | Extraterritorial | 2024 |
| CWT Partners Ltd | Administrative & support | 2014 |
| Cyberdyne AGI Systems Limited | Manufacturing | 2026 |
| Cycling Made Easy Limited | Wholesale & retail | 2010 |
| Cycx Limited | Information & communication | 2023 |
| CZ Homes Ltd | Real estate | 2020 |
| CZR UK Logistics Ltd | Administrative & support | 2018 |
| D & Build Ltd | Construction | 2022 |
| D & L Epsom Limited | Other services | 2017 |
| D Brand Electrical Services Ltd | Construction | 2016 |
| D F M Nominees Limited | Extraterritorial | 1987 |
| D Hillier Refurbishments Limited | Construction | 2007 |
| D I Worrall Controls Limited | Construction | 2014 |
| D S Golf Event Management Limited | Arts & recreation | 2017 |
| D Squared Consulting Limited | Administrative & support | 1998 |
| D&C Pipelines (Medway) Ltd | Construction | 2025 |
| D&F Cars Ltd | Wholesale & retail | 2024 |
| D&L Residences Ltd | Real estate | 2025 |
| D&M Coachworks Limited | Wholesale & retail | 2021 |
| D. P. Fuller Limited | Construction | 2016 |
| D.C.R. and Sons Limited | Construction | 2015 |
| D.G.Jacobi Limited | Arts & recreation | 1964 |
| D.M. Associates Limited | Administrative & support | 1993 |
| D.N.S. Management Company Limited | Real estate | 1981 |
| D.S Surveying Solutions Limited | Professional & scientific | 2020 |
| D2D Travel Ltd | Administrative & support | 2023 |
| D4MS Technology Limited | Information & communication | 2013 |
| Daay Transport Ltd | Transport & logistics | 2023 |
| DAE Property Investments Limited | Real estate | 2022 |
| Daisih Limited | Households | 2025 |
| Daisy AI Limited | Professional & scientific | 2024 |
| Dalbani (U.K.) Limited | Wholesale & retail | 1989 |
| Daminice Care Limited | Health & social care | 2015 |
| Dancing Barrell Limited | Hospitality | 2026 |