| CJO Technologies Limited | Professional & scientific | 2024 |
| Cjrj Properties Limited | Real estate | 2013 |
| Cjrt Ltd | Hospitality | 2025 |
| CJS Hygiene and Safety Limited | Professional & scientific | 2015 |
| CJT Software Ltd | Information & communication | 2016 |
| Cjuk Limited | Manufacturing | 2025 |
| CK Aesthetic Supplies Ltd | Wholesale & retail | 2023 |
| CK Douglas Limited | Real estate | 2014 |
| CK Douglas Services Limited | Hospitality | 2019 |
| CK Electrical Contractors Ltd | Construction | 2022 |
| CK Foods Yorkshire Ltd | Hospitality | 2022 |
| CK Henderson Petpics Limited | Professional & scientific | 2023 |
| CK Kumar Ltd | Wholesale & retail | 2014 |
| CK Land Investments Limited | Real estate | 2019 |
| CK Sparks Ltd | Construction | 2024 |
| CKB Estates Limited | Real estate | 2017 |
| CKC Group Ltd | Financial services | 2026 |
| CKD Property Limited | Real estate | 2023 |
| Ckell Ltd | Hospitality | 2025 |
| CKK Design Limited | Professional & scientific | 2004 |
| CKM Grace Ltd | Health & social care | 2015 |
| CL Bartle Consultancy Ltd | Other services | 2021 |
| CL Consulting Ltd | Information & communication | 2016 |
| CL Investment Group Ltd | Households | 2019 |
| CL Realisations Limited | Professional & scientific | 1994 |
| Cladhall Ltd | Construction | 2018 |
| Claim 4 Misleading Financial Advice Limited | Financial services | 2019 |
| Claims Investigation Group Ltd | Administrative & support | 2016 |
| Claims Management Solutions Ltd | Other services | 2021 |
| Claire Benson Hairdressing Limited | Other services | 2014 |
| Claire Court Management (Leeds) Limited | Households | 1989 |
| Claire COX Interiors Limited | Professional & scientific | 2018 |
| Claire Homecare Ltd | Wholesale & retail | 2026 |
| Claire Jones Limited | Other services | 2003 |
| Claire Louise Photography Limited | Other services | 2015 |
| Claire Oliver Comedy Ltd | Arts & recreation | 2026 |
| Claire Ramsbottom Property Management Limited | Real estate | 2026 |
| Claire Ramsbottom Sales Limited | Real estate | 2019 |
| Claire Rutherford Limited | Professional & scientific | 2013 |
| Clairem Limited | Wholesale & retail | 2025 |
| Clampco (UK) Limited | Wholesale & retail | 2001 |
| Clandestine Books Limited | Information & communication | 2014 |
| Clara Fashions Ltd | Wholesale & retail | 2019 |
| Clara Property Limited | Construction | 2023 |
| Clara Trading Limited | Wholesale & retail | 2025 |
| Claras DEN York Ltd | Real estate | 2026 |
| Clare Bruce Limited | Professional & scientific | 2016 |
| Clare Lloyd Solutions Ltd | Professional & scientific | 2020 |
| Claremont & Smith Ltd | Health & social care | 2015 |
| Claremont Litigation Limited | Professional & scientific | 2013 |
| Clarence Street York Limited | Construction | 2020 |
| Clarendon Coaching Limited | Professional & scientific | 2022 |
| Clarendon Dental Spa (Leeds) Limited | Health & social care | 2014 |
| Clarendon Dental Spa LLP | | 2007 |
| Clarendon Road (Block B) RTM Co Limited | Households | 2023 |
| Clarendon Road (Block C) RTM Co Limited | Households | 2023 |
| Clarendon Road(Block a) RTM Co Limited | Households | 2023 |
| Clariant Holdings UK Ltd | Professional & scientific | 1984 |
| Clariant Horsforth Limited | Professional & scientific | 2000 |
| Clariant OIL Services UK Ltd | Manufacturing | 1975 |
| Clariant Production UK Ltd | Wholesale & retail | 1997 |
| Clariant Services UK Ltd | Professional & scientific | 1995 |
| Clariant Trustees Limited | Financial services | 1996 |
| Clariant UK Ltd | Professional & scientific | 2001 |
| Claridge & Hill Ltd | Real estate | 2022 |
| Clarifo Developers Ltd | Information & communication | 2026 |
| Clarion Advisory LLP | | 2016 |
| Clarion Computers Limited | Information & communication | 1999 |
| Clarion Interpreting Limited | Other services | 2002 |
| Clarion Solicitors Limited | Professional & scientific | 2010 |
| Clarion Trust Corporation Limited | Administrative & support | 2019 |
| Clariscan Imaging Ltd | Other services | 2025 |
| Clarissa Dakin Limited | Professional & scientific | 2021 |
| Clarity Cart Ltd | Wholesale & retail | 2025 |
| Clarity Project Consulting Limited | Professional & scientific | 2016 |
| Clarity Translation & Interpreting Limited | Education | 2025 |
| Clarity Wealth Limited | Financial services | 2016 |
| Clarivo Group Ltd | Information & communication | 2026 |
| Clark and Associates Limited | Health & social care | 2018 |
| Clark Business Recovery Limited | Administrative & support | 2007 |
| Clark Construction Leeds Limited | Construction | 2025 |
| Clark Family Law Ltd | Other services | 2018 |
| Clark Haulage Limited | Transport & logistics | 2025 |
| Clark Inspection Services Ltd | Professional & scientific | 2019 |
| Clark Miller Properties Ltd | Real estate | 2021 |
| Clark Property Investments Ltd | Real estate | 2020 |
| Clarke & Co Roofing Services Ltd | Construction | 2025 |
| Clarke Bishop Properties Limited | Real estate | 2024 |
| Clarke Communications Limited | Construction | 2012 |
| Clarke Electrical Solutions Limited | Construction | 2019 |
| Clarke EV Ltd | Extraterritorial | 2020 |
| Clarke Telecom Limited | Information & communication | 2011 |
| Clarke's Management & Engineering Services Ltd | Professional & scientific | 2022 |
| Clarke-Scott Real Estate Ltd | Real estate | 2025 |
| Clarks Independence Centre Ltd | Manufacturing | 2011 |
| Clarks Independence Centre Properties Ltd | Real estate | 2020 |
| Clarkson Security Ltd | Manufacturing | 2013 |
| Clashstreetco LLP | | 2012 |
| Clasico Kits Ltd | Wholesale & retail | 2024 |
| Class One Driver Management Consultancy Limited | Professional & scientific | 2015 |