| Creative Nails 53 Ltd | Other services | 2025 |
| Creative Quest Ltd | Wholesale & retail | 2023 |
| Crendian Express Limited | Hospitality | 2025 |
| Crescent Enterprises Limited | Real estate | 2004 |
| Crescent Park Limited | Hospitality | 2017 |
| Crest Bits Limited | Professional & scientific | 2024 |
| CRI Reels Limited | Administrative & support | 2010 |
| Cricklade Kitchen Limited | Hospitality | 2025 |
| Crintea Ltd | Construction | 2025 |
| Crisp Projects & Interiors Ltd | Construction | 2026 |
| Croft & Cole Ltd | Wholesale & retail | 2018 |
| Cromer Court (Finedon) Management Company Limited | Households | 2007 |
| Cromwale Limited | Transport & logistics | 2024 |
| Cromwell House (Boxmoor) Management Company Limited | Households | 2018 |
| Crossco Luton Limited | Administrative & support | 2013 |
| Crowdsaffron Limited | Information & communication | 2015 |
| Crowe Dent Repair Limited | Wholesale & retail | 2023 |
| Crown Aerospace Limited | Transport & logistics | 1999 |
| Crown Carpentry and Construction Limited | Construction | 2015 |
| Crown Restoration Ltd | Construction | 2026 |
| CROWNPROPERTY4YOU Ltd | Real estate | 2026 |
| Crowns Electrical Limited | Construction | 2023 |
| CRUSADER9 Ltd | Arts & recreation | 2023 |
| Crwnvault Ltd | Wholesale & retail | 2026 |
| Cryotalent Ltd | Administrative & support | 2025 |
| Crystal Cleaning Watford Ltd | Administrative & support | 2018 |
| Crystal View Limited | Hospitality | 2026 |
| Crystaltrans Ltd | Transport & logistics | 2021 |
| CSF Load Ltd | Wholesale & retail | 2025 |
| CSI Luton Limited | Real estate | 2024 |
| CSM Dominic Ltd | Construction | 2018 |
| CSM Estera Ltd | Wholesale & retail | 2022 |
| CSM Global Limited | Wholesale & retail | 2022 |
| CSM Property Development Company Ltd | Construction | 2024 |
| CSM TM Ltd | Construction | 2024 |
| CSS Property Holdings Ltd | Real estate | 2026 |
| CT Maintenance and Landscaping Ltd | Construction | 2026 |
| CT Perva Limited | Other services | 2017 |
| CT Transporter Ltd | Transport & logistics | 2013 |
| CTD Utilities Limited | Construction | 2019 |
| Cumberise Limited | Construction | 2013 |
| Curate Your Genius CIC | Information & communication | 2025 |
| Curek Ltd | Wholesale & retail | 2025 |
| Curelaru Services Limited | Construction | 2026 |
| Curious ACT Ltd | Wholesale & retail | 2025 |
| Curry Garden (Dunstable) Ltd | Hospitality | 2000 |
| Curry Land Pboro Ltd | Hospitality | 2020 |
| Curry Spice Kitchen Limited | Hospitality | 2024 |
| Curryhills Civil Engineering Ltd | Construction | 2014 |
| Curryhills Investments Limited | Construction | 2024 |
| Curvature Projects Ltd | Manufacturing | 2023 |
| Custom Property Management Ltd | Other services | 2025 |
| CUT and Edge Manufacturing Services Ltd | Manufacturing | 2026 |
| CVB Construct Ltd | Construction | 2018 |
| CVL Transport Limited | Transport & logistics | 2022 |
| CW Investments Ltd | Real estate | 2016 |
| CWG Install Limited | Construction | 2026 |
| CWM Survey & Inspection UK Ltd | Manufacturing | 2024 |
| CX Health Technologies Ltd | Information & communication | 2010 |
| CY Cares Ltd | Health & social care | 2025 |
| Cybaassess Ltd | Health & social care | 2025 |
| Cyber Global UK Ltd | Information & communication | 2024 |
| Cyberbex Limited | Information & communication | 2016 |
| Cyberfied Ltd | Education | 2024 |
| CYC Group Limited | Real estate | 2024 |
| Cycle-Kit Limited | Administrative & support | 2002 |
| Cyclepower UK Limited | Professional & scientific | 2005 |
| Cyclops Design and Print Limited | Manufacturing | 2021 |
| D & E Carpentry Ltd | Construction | 2007 |
| D & J Taverns Limited | Hospitality | 2021 |
| D & K Wiring Services Limited | Manufacturing | 1985 |
| D & S White Swan Limited | Hospitality | 2005 |
| D & T Roofing Limited | Construction | 2019 |
| D & V Ventilation Ltd | Construction | 2024 |
| D Arch Heating Services Limited | Administrative & support | 2003 |
| D Cookman Electrical Ltd | Construction | 2021 |
| D D Services M & E Limited | Construction | 2017 |
| D J Russell Associates Limited | Extraterritorial | 2013 |
| D J Russell Builders Limited | Construction | 1998 |
| D J Russell Contractors Limited | Construction | 2006 |
| D J Russell Estates Limited | Administrative & support | 2000 |
| D J Russell Homes Limited | Extraterritorial | 2013 |
| D J Russell Investments Limited | Administrative & support | 1999 |
| D J Russell Property Limited | Administrative & support | 2000 |
| D P O Building Contractors Limited | Construction | 2008 |
| D P O Developments Limited | Construction | 2006 |
| D P Pool Services Limited | Other services | 2016 |
| D P Properties (Bedfordshire) Ltd | Real estate | 2025 |
| D Pugh Investments Limited | Hospitality | 2017 |
| D Pugh Property Limited | Real estate | 2025 |
| D T B Grab Hire Ltd | Construction | 2024 |
| D Tech Maintenance Ltd | Administrative & support | 2015 |
| D&A TOM Trans Ltd | Transport & logistics | 2018 |
| D&D Pro Ltd | Information & communication | 2017 |
| D&J Company Ltd | Hospitality | 2019 |
| D&M Quality Cars Ltd | Wholesale & retail | 2023 |
| D&N Pension Projects Ltd | Administrative & support | 2010 |
| D&R Mechanics Ltd | Wholesale & retail | 2019 |
| D.A.M.C. Solutions Ltd | Manufacturing | 2018 |
| D.J. Kefford BSC QS Services Limited | Professional & scientific | 2008 |