| Church Wharf Garage Limited | Wholesale & retail | 2008 |
| Churchgate Hospitality Ltd | Hospitality | 2023 |
| Churnvale Limited | Administrative & support | 1964 |
| Chuuvam Ltd | Arts & recreation | 2025 |
| Chuv Studio Ltd | Professional & scientific | 2024 |
| CHW Accounting Limited | Financial services | 2012 |
| CI Solutions Holdings Limited | Health & social care | 2020 |
| CI Wagstaff Ltd | Transport & logistics | 2023 |
| Cibus Energy Limited | Administrative & support | 2024 |
| Cidron Neptune Bidco Limited | Financial services | 2020 |
| Cidron Neptune Midco Limited | Financial services | 2020 |
| Cidron Neptune Topco Limited | Financial services | 2020 |
| Ciere Ltd | Professional & scientific | 2023 |
| CIF Management Consultants Limited | Professional & scientific | 2011 |
| Ciii Limited | Administrative & support | 2021 |
| Cinar Logistics Ltd | Wholesale & retail | 2022 |
| Cinch Technology Limited | Wholesale & retail | 2020 |
| Cineloop Ltd | Health & social care | 2023 |
| Cintel Holdings Limited | Professional & scientific | 2017 |
| Cintel Structural Consultants Limited | Professional & scientific | 2010 |
| Ciné Schools Ltd | Education | 2021 |
| Cipher Labs Ltd | Information & communication | 2026 |
| Ciphertrade Ltd | Professional & scientific | 2021 |
| Cipotrans Limited | Transport & logistics | 2025 |
| Circe Coaching Limited | Administrative & support | 2021 |
| Circle Liverpool Limited | Extraterritorial | 2000 |
| Circle of Inspirational Calm C.I.C. | Public administration | 2023 |
| Circle Recycling Limited | Water & waste | 2003 |
| Circlet Limited | Real estate | 2019 |
| Circuit Component Supplies Ltd | Manufacturing | 2003 |
| Circuit Nova Ltd | Information & communication | 2024 |
| Cirkel Studio Ltd | Information & communication | 2009 |
| Citi Medical Limited | Health & social care | 2014 |
| Citizens Advice Bury and Bolton Limited | Administrative & support | 2004 |
| City and County Planning Limited | Professional & scientific | 2026 |
| City and Suburb Homes Ltd | Real estate | 2019 |
| City Boss Ltd | Wholesale & retail | 2019 |
| City Car Centre (MCR) Limited | Wholesale & retail | 2024 |
| City Developments (Project Management) Limited | Construction | 2020 |
| City Homes (UK) Ltd | Construction | 2014 |
| City Linen GB Ltd | Other services | 2019 |
| City Motor Group Ltd | Wholesale & retail | 2026 |
| City Sports & Cocktail Bar Ltd | Hospitality | 2024 |
| City Tavern Limited | Hospitality | 2019 |
| City Wide Waste Services Ltd | Water & waste | 2024 |
| Cityfocus Limited | Real estate | 1981 |
| Cityking Properties Ltd | Real estate | 2000 |
| Citymeade Holdings Ltd | Financial services | 2025 |
| Citymeade Limited | Financial services | 2023 |
| Citystreets Limited | Real estate | 2003 |
| Civica Property Limited | Real estate | 2024 |
| Civicore CIC | Other services | 2025 |
| Civil & Fibre Ltd | Information & communication | 2020 |
| Civil and Structural Services Limited | Professional & scientific | 2022 |
| CIVIL2LEGAL Limited | Administrative & support | 2019 |
| CIX Consulting Limited | Information & communication | 2025 |
| CJ Cafe Milkbar Ltd | Hospitality | 2025 |
| CJ Commissioning Limited | Construction | 2026 |
| CJ Contracting Services Ltd | Transport & logistics | 2025 |
| CJ Fiala Limited | Professional & scientific | 2026 |
| CJ Properties Management Ltd | Real estate | 2019 |
| CJ Renewables Ltd | Professional & scientific | 2011 |
| Cjce Consulting Ltd | Information & communication | 2022 |
| CJH Deliveries Ltd | Transport & logistics | 2026 |
| CJL Consultants NW Limited | Construction | 2023 |
| CJL Property Investments Ltd | Real estate | 2023 |
| CJL Tyres and Autocare Ltd | Wholesale & retail | 2025 |
| CJM Heating & Plumbing Limited | Construction | 2023 |
| CJM Tiling Contractors Ltd | Construction | 2017 |
| CJN Control Solutions Ltd | Administrative & support | 2016 |
| CJP Building Consultancy Ltd | Professional & scientific | 2024 |
| Cjps Properties Ltd | Real estate | 2022 |
| CJS Software Systems Limited | Information & communication | 2000 |
| CJS Surveyors Ltd | Professional & scientific | 2023 |
| CK Business Support Ltd | Professional & scientific | 2024 |
| CK Commercial Vehicles Ltd | Manufacturing | 2024 |
| CK Food Courier Ltd | Hospitality | 2025 |
| CKB Recruitment Ltd | Administrative & support | 2017 |
| CKG Engineering Limited | Administrative & support | 2011 |
| Ckjt Limited | Professional & scientific | 2022 |
| CKM Transport Ltd | Transport & logistics | 2005 |
| CKT UK Solutions Ltd | Public administration | 2024 |
| CL Automotive Limited | Manufacturing | 2003 |
| CL Fitout Limited | Construction | 2023 |
| Cladmain Ltd | Construction | 2025 |
| Claim Services Ltd | Professional & scientific | 2025 |
| Claims Hire Ltd | Professional & scientific | 2024 |
| Claims Manager NW Ltd | Professional & scientific | 2008 |
| Claire Dickens Consulting Ltd | Professional & scientific | 2025 |
| Claire Jane Hobson Ltd | Other services | 2014 |
| Claire Luxury Travel Limited | Administrative & support | 2025 |
| Clan Martin Ltd | Wholesale & retail | 2021 |
| Clare Construction Limited | Construction | 2024 |
| Clare Design and Build Limited | Construction | 2018 |
| Clare Louise Limited | Health & social care | 2022 |
| Clare Wright Properties Ltd | Real estate | 2024 |
| Clarebank Property Holdings Ltd | Real estate | 2025 |
| Claremont House Enterprises Ltd | Transport & logistics | 2024 |
| Clarence House Holdings Limited | Administrative & support | 2015 |
| Clarendon DSM Limited | Professional & scientific | 2015 |