| Clarence NO 2 Limited | Financial services | 2020 |
| Clarendon Avenue RTM Company Limited | Households | 2026 |
| Clarendon Cottage School Limited | Education | 2000 |
| Clarendon Cottages (Styal) Management Company Limited | Households | 2003 |
| Clarendon Homes Ltd | Construction | 2011 |
| Clarendon Place Management Company (UK) Limited | Households | 2006 |
| Clarendon Welfare Centre Ltd | Education | 2024 |
| Claret Civil Engineering Limited | Construction | 1994 |
| Clariant Distribution UK Ltd | Professional & scientific | 1966 |
| Clarico Media Ltd | Professional & scientific | 2025 |
| Claridge Control Systems Limited | Professional & scientific | 2002 |
| Clarion Call Communications Ltd | Professional & scientific | 2021 |
| Claris' Kitchen Limited | Extraterritorial | 2012 |
| Clarit 360 Ltd | Information & communication | 2026 |
| Claritas Translations Ltd | Professional & scientific | 2025 |
| Claritax Accountants Ltd | Professional & scientific | 2020 |
| Claritax Trustees Ltd | Professional & scientific | 2021 |
| Clarity & Claims Ltd | Administrative & support | 2025 |
| Clarity Aesthetics Limited | Health & social care | 2020 |
| Clarity Bridge 11 Limited | Wholesale & retail | 2020 |
| Clarity C Limited | Real estate | 2022 |
| Clarity Clinics Limited | Health & social care | 2020 |
| Clarity Counselling Services Limited | Health & social care | 2024 |
| Clarity Dental Clinic Limited | Health & social care | 2018 |
| Clarity Developments Ltd | Construction | 2014 |
| Clarity Events Managment MCR Ltd | Manufacturing | 2024 |
| Clarity Glass Ltd | Manufacturing | 2018 |
| Clarity Hardware Ltd | Wholesale & retail | 2020 |
| Clarity HIK Ltd | Real estate | 2024 |
| Clarity Homecare (Bury) Ltd | Health & social care | 2019 |
| Clarity JM Ltd | Health & social care | 2023 |
| Clarity LED Limited | Wholesale & retail | 2016 |
| Clarity MCR Limited | Construction | 2014 |
| Clarity Networks Ltd | Extraterritorial | 2022 |
| Clarity Optics Limited | Health & social care | 2016 |
| Clarity Recruitment to Recruitment Limited | Administrative & support | 2008 |
| Clarity Repairs Limited | Construction | 2016 |
| Clarity Rfid Limited | Information & communication | 2025 |
| Clarity Travel Limited | Administrative & support | 2010 |
| Clarity VIP Limited | Real estate | 2012 |
| Clarityb Consulting Limited | Professional & scientific | 2013 |
| Clarix Ltd | Professional & scientific | 2026 |
| Clariyo Ltd | Professional & scientific | 2025 |
| Clarjo Ltd | Professional & scientific | 2014 |
| Clark Sinclair Limited | Administrative & support | 2023 |
| Clarke & Edwards Ltd | Real estate | 2006 |
| Clarke & Jones Ltd | Other services | 2017 |
| Clarke & Watt Building Consultancy Ltd | Professional & scientific | 2020 |
| Clarke Bell Limited | Administrative & support | 2004 |
| Clarke Capital Group Limited | Financial services | 2023 |
| Clarke Controls Group Limited | Manufacturing | 2025 |
| Clarke Controls Limited | Manufacturing | 2003 |
| Clarke Gardening Ltd | Administrative & support | 2023 |
| Clarke Gough Joinery Limited | Construction | 2001 |
| Clarke Hendrik Global Ltd | Financial services | 2025 |
| Clarke Hendrik Group Ltd | Financial services | 2021 |
| Clarke Roberts Recruitment Limited | Administrative & support | 2012 |
| Clarke Services Engineering Group Limited | Professional & scientific | 2012 |
| Clarke-Taylor Ltd | Health & social care | 2018 |
| Clarkes Taverns UK Ltd | Hospitality | 2020 |
| Clarks Hill (Prestwich) Management Limited | Households | 2004 |
| Clarkson Bespoke Ltd | Professional & scientific | 2020 |
| Clarkson LEE Bespoke Ltd | Professional & scientific | 2025 |
| Clarkson LEE Construction Ltd | Construction | 2021 |
| Clarkston Controls Limited | Other services | 2012 |
| Claros Holdings Limited | Public administration | 2026 |
| Claros Operations Limited | Public administration | 2026 |
| Clarus Software Ltd | Information & communication | 2014 |
| Claryty Mind Ltd | Other services | 2026 |
| Clasal Limited | Wholesale & retail | 2016 |
| Class Beauty Ltd | Other services | 2025 |
| Class Beauty Whitington Ltd | Other services | 2026 |
| Class Cleaning Services Limited | Administrative & support | 2019 |
| Class Direct Ltd | Administrative & support | 2025 |
| Class Glass Installs Ltd | Construction | 2025 |
| Class Hair Salon Ltd | Other services | 2019 |
| Class Holdings Limited | Professional & scientific | 2016 |
| Class of 92 Limited | Arts & recreation | 2012 |
| Class One 21 Ltd | Wholesale & retail | 2021 |
| Class S Digital Ltd | Wholesale & retail | 2025 |
| Classic and Camper Ltd | Other services | 2020 |
| Classic Art Pictures Limited | Manufacturing | 1985 |
| Classic Bedding Limited | Wholesale & retail | 2021 |
| Classic Bootique Limited | Wholesale & retail | 2026 |
| Classic Cafe (London) Limited | Hospitality | 2017 |
| Classic Car Panels Ltd | Wholesale & retail | 2021 |
| Classic Cars Services Limited | Other services | 2023 |
| Classic Catering Ltd | Hospitality | 2023 |
| Classic Catering Northwest Limited | Hospitality | 2025 |
| Classic Collection Aviation Limited | Administrative & support | 1995 |
| Classic Collection Holdings Limited | Administrative & support | 2018 |
| Classic Collection Holidays Limited | Administrative & support | 1980 |
| Classic Combination Limited | Professional & scientific | 1936 |
| Classic Comfort Limited | Wholesale & retail | 2025 |
| Classic Construction & Paving Limited | Construction | 2022 |
| Classic Construction Limited | Construction | 2005 |
| Classic Deals Limited | Wholesale & retail | 2026 |
| Classic Education Limited | Professional & scientific | 2005 |
| Classic Hair Ltd | Other services | 2026 |
| Classic Kitchen Services Ltd | Hospitality | 2025 |