| CSL Design Ltd | Professional & scientific | 2022 |
| CSL Property Holdings Limited | Real estate | 2024 |
| Cspt Limited | Administrative & support | 2010 |
| CSS Finance Limited | Professional & scientific | 2022 |
| CSS Networks Limited | Information & communication | 2003 |
| CSW Contract Management Ltd | Professional & scientific | 2011 |
| CT Biotech Consulting Ltd | Professional & scientific | 2024 |
| CT Concept Limited | Administrative & support | 2018 |
| CT Design Cheshire Limited | Wholesale & retail | 2021 |
| CT Software Testing Solutions Limited | Professional & scientific | 2023 |
| Ctouch UK Limited | Wholesale & retail | 2018 |
| Ctrl+ Sisters Ltd | Administrative & support | 2025 |
| Cubby House Developments Ltd | Real estate | 2023 |
| Cube Street Furniture Ltd | Wholesale & retail | 2024 |
| CUBE121 Ltd | Professional & scientific | 2015 |
| CUBE15 Engineering Limited | Professional & scientific | 2015 |
| Cubedigico UK Ltd | Information & communication | 2020 |
| Cubes and Stones Infra Limited | Construction | 2023 |
| Cubespace Satellite Systems Limited | Manufacturing | 2024 |
| Cubic Trade Limited | Wholesale & retail | 2023 |
| CUBIC110 Limited | Real estate | 2022 |
| Cucina Centrale Ltd | Hospitality | 2025 |
| Cudenweb Limited | Administrative & support | 2016 |
| Cuiping Company Ltd | Hospitality | 2018 |
| Cula Projects Ltd | Construction | 2021 |
| Cult Beauty Limited | Wholesale & retail | 2007 |
| Culture Builder Limited | Professional & scientific | 2025 |
| Culturepulse Ltd | Information & communication | 2025 |
| Cumnock Investments Limited | Real estate | 2014 |
| Cumulus Acquisition Limited | Financial services | 2019 |
| Cunning Plan Marketing Limited | Administrative & support | 2009 |
| Cura Health Diagnostics Ltd | Health & social care | 2022 |
| Curenow Investments Ltd | Real estate | 2016 |
| Curenow Ltd | Health & social care | 2014 |
| Current Lighting Limited | Wholesale & retail | 1986 |
| Curriculo Partners Limited | Information & communication | 2025 |
| Curry Mile Ltd | Hospitality | 2024 |
| Curtis Consultancy Limited | Professional & scientific | 2020 |
| Curtis Faraday Insolvency Limited | Other services | 2025 |
| Curtis Faraday Limited | Other services | 2008 |
| Curves Photography Studios Ltd | Professional & scientific | 2017 |
| Curzon North West Ltd | Construction | 2015 |
| Curzon Park (Ashton-Under-Lyne) Management Company Limited | Households | 2005 |
| Custom Landscape Designs Limited | Construction | 2018 |
| Custom NW Limited | Real estate | 2020 |
| Custom Renovations Limited | Construction | 2012 |
| Cute Craft Ltd. | Wholesale & retail | 2018 |
| Cuthberts Hairdressing Limited | Other services | 2012 |
| Cutting Edge Dental Education Ltd | Education | 2018 |
| CV Hale Ltd | Hospitality | 2023 |
| CVG Consulting Limited | Administrative & support | 2023 |
| CVI Consulting Limited | Administrative & support | 2022 |
| CVS Limited | Information & communication | 2007 |
| CW Solutions Limited | Professional & scientific | 2020 |
| CWT Consulting Ltd | Professional & scientific | 2025 |
| CX Automation Limited | Professional & scientific | 2025 |
| Cyber Defence Solutions Limited | Professional & scientific | 2025 |
| Cyber Security Specialists Limited | Information & communication | 2015 |
| Cybercube Analytics Europe Limited | Information & communication | 2017 |
| Cyberdane Limited | Administrative & support | 2014 |
| Cyberkloud Consulting Limited | Professional & scientific | 2023 |
| Cycle of Life Project CIC | Arts & recreation | 2025 |
| Cydex Ltd | Information & communication | 2025 |
| Cyma Petroleum (UK) Limited | Wholesale & retail | 1997 |
| Cymark Dealer Services Limited | Administrative & support | 2000 |
| Cyphere Ltd | Information & communication | 2020 |
| Cyprian Solutions Limited | Professional & scientific | 2023 |
| Cytospire Therapeutics Limited | Professional & scientific | 2023 |
| D & S Properties Partnership LLP | | 2023 |
| D & T Eyecare Ltd | Health & social care | 2025 |
| D & Z Properties Ltd | Real estate | 2022 |
| D and J Insight Limited | Professional & scientific | 2014 |
| D Associates Ltd | Professional & scientific | 2008 |
| D Burns Pet Treats Limited | Wholesale & retail | 2005 |
| D C M Electrical Installations Ltd | Construction | 2007 |
| D Freebairn Ltd | Arts & recreation | 2024 |
| D Hughes Demolition & Excavation Limited | Water & waste | 1998 |
| D Hurlstone Limited | Professional & scientific | 2009 |
| D J L Plastering Contractors Ltd | Construction | 2019 |
| D J M Dairies Limited | Hospitality | 2006 |
| D Johnston & Associates Limited | Professional & scientific | 2018 |
| D Ludford Capital Limited | Other services | 2023 |
| D O Dermatology Ltd | Health & social care | 2022 |
| D OD Property Ltd | Real estate | 2023 |
| D Rehm Limited | Administrative & support | 2016 |
| D Shea Limited | Real estate | 2020 |
| D Stewart Enterprises Limited | Administrative & support | 2013 |
| D&A Martell Ltd | Financial services | 2023 |
| D&C Estate Management Ltd | Real estate | 2025 |
| D&I Global Sales Ltd | Wholesale & retail | 2025 |
| D&J Technology Solutions Limited | Information & communication | 2024 |
| D&S Investment Holdings Ltd | Professional & scientific | 2017 |
| D&U Decor Ltd | Construction | 2024 |
| D&W Property Ltd | Real estate | 2025 |
| D'Urton Yard (Broughton) Management Company Limited | Real estate | 2018 |
| D. Murray Construction Limited | Construction | 1998 |
| D.E.Worthington Limited | Real estate | 1955 |
| D.J.Financial Solutions Limited | Financial services | 2014 |
| D.M.R. & Co. (Creative Jewellery) Limited | Professional & scientific | 1975 |
| D3B Design Ltd. | Information & communication | 2010 |