| Church Court Management Company (Stilton) Limited | Households | 1988 |
| Church Farm Investments Ltd | Real estate | 2011 |
| Church Lane (Tarleton) Management Company Limited | Households | 2003 |
| Church Mews Management Company (Mitcham) Limited | Households | 1988 |
| Church Road Croydon (Resi) Ltd | Real estate | 2015 |
| Church Road Croydon Ltd | Real estate | 2014 |
| Church Road Mews Ltd | Households | 2025 |
| Church ST Psychiatry Limited | Health & social care | 2024 |
| Church View (Tisbury) Management Company Limited | Households | 2007 |
| Church View Management Company (Bristol) Limited | Households | 2006 |
| Church View Management Company Limited | Households | 1989 |
| Church Walk (Wallasey) Management Company Limited | Households | 2007 |
| Churchfield View (Bolney) Management Company Limited | Households | 2022 |
| Churchford Flat Management Company Limited | Households | 1977 |
| Churchgate Plaza Management Company Limited | Households | 2006 |
| Churchill House (Addlestone) Limited | Households | 2011 |
| Churchstreet Corp Ltd | Professional & scientific | 2026 |
| Churchville Limited | Administrative & support | 1988 |
| Chute Holdings Limited | Financial services | 2026 |
| CI TUA Ltd | Hospitality | 2020 |
| Cian Property Limited | Real estate | 2019 |
| Ciel Infinite Ltd | Information & communication | 2023 |
| Ciera Stone & Terrazzo Limited | Manufacturing | 2025 |
| Ciesielski Delivery Ltd | Transport & logistics | 2024 |
| Cigaronne International Limited | Other services | 2000 |
| Cillian and Co Limited | Real estate | 2018 |
| Cinar Construction Limited | Construction | 2020 |
| Cinchona Investments Limited | Real estate | 2017 |
| Cindel Studio Limited | Professional & scientific | 2020 |
| Cindy Patch Ltd | Health & social care | 2024 |
| Cindymo Ltd | Wholesale & retail | 2018 |
| Cinematic Curations Limited | Professional & scientific | 2025 |
| Cingh Global Products Private Limited | Wholesale & retail | 2025 |
| Cinnabar House RTM Company Limited | Households | 2018 |
| Cinnex Limited | Hospitality | 2025 |
| Cinque Port Cars Limited | Transport & logistics | 2013 |
| Cinvesto Ltd | Professional & scientific | 2025 |
| Cipsce Ltd | Transport & logistics | 2019 |
| Circa Apartments Residents Management Company Limited | Households | 2003 |
| Circle Care Solutions Ltd | Administrative & support | 2026 |
| Citadel Financial Intermediary Ltd | Financial services | 2015 |
| Citi Homestays Ltd | Real estate | 2023 |
| Citi Partners Business Advisers Ltd | Professional & scientific | 2012 |
| Citi Partners Tax Advisers Ltd | Professional & scientific | 2012 |
| Citisuites Limited | Extraterritorial | 2011 |
| Citizen Journalism Educational Trust Limited | Education | 2008 |
| Citizenbay Limited | Professional & scientific | 2004 |
| Citizensound Limited | Extraterritorial | 2007 |
| Citrine Properties Limited | Real estate | 2017 |
| City Accountancy Ltd | Professional & scientific | 2013 |
| City ASC Ltd | Education | 2020 |
| City Build Services Limited | Construction | 2019 |
| City Convenience Limited | Real estate | 2020 |
| City Heights Management Company Limited | Households | 1998 |
| City Homes Group Limited | Real estate | 2020 |
| City Learning Hub Ltd | Wholesale & retail | 2020 |
| City Locations Block Management Limited | Real estate | 2014 |
| City Locations Limited | Real estate | 2011 |
| City Masonry Limited | Construction | 2010 |
| City Quays (Chester) Management Company Limited | Households | 2004 |
| City Spa London Ltd | Other services | 2025 |
| Citylink Estates Limited | Real estate | 2008 |
| Citywise Property Solutions Ltd | Professional & scientific | 2026 |
| Civenger Ltd | Professional & scientific | 2016 |
| CIX Limited | Administrative & support | 2023 |
| CJ DEA Ltd | Wholesale & retail | 2015 |
| CJA Holdings Limited | Financial services | 2018 |
| CJD Limited | Transport & logistics | 2015 |
| Cjjn Ltd | Real estate | 2026 |
| CJM Property Investments Limited | Real estate | 2003 |
| Cjsykes Ltd | Health & social care | 2020 |
| CJT Project Management Limited | Real estate | 2018 |
| CJW Installations Ltd | Construction | 2017 |
| CK Business Services Ltd | Professional & scientific | 2015 |
| CK Fitness Coaching Ltd | Other services | 2021 |
| CK Ironing Service Ltd | Administrative & support | 2023 |
| Ckan Ltd | Information & communication | 2011 |
| Ckma Group Limited | Financial services | 2025 |
| Ckma Limited | Financial services | 2019 |
| CKT Cisco Contracting Limited | Professional & scientific | 2013 |
| Cladish & Company Limited | Wholesale & retail | 1949 |
| Claim Time Solution Ltd | Other services | 2016 |
| Clair & Kahlon Limited | Wholesale & retail | 2025 |
| Clannan Healthcare Ltd | Health & social care | 2020 |
| Clapham Coffee Ltd | Hospitality | 2015 |
| Clara Health Ltd | Health & social care | 2023 |
| Clare Court Limited | Households | 1988 |
| Clare Lodge (Sutton) Management Company Limited | Real estate | 2004 |
| Claremont Court (Biggleswade) Ltd | Households | 2003 |
| Clarence Place (Bracknell) Residents Management Company Limited | Households | 2015 |
| Clarence Road RTM Company Limited | Households | 2006 |
| Clarendon Amenity Limited | Households | 1981 |
| Clarendon Court Number 2 (Beckenham) Management Company Limited | Households | 1988 |
| Clarendon Park Residents Management Company Limited | Households | 1994 |
| Clarendons Group Limited | Extraterritorial | 2017 |
| Clarendons Investments Limited | Real estate | 2018 |
| Clarendons Kent Limited | Households | 2021 |
| Clarendons Property Consultants Limited | Real estate | 2010 |
| Clarendons Residential Ltd | Real estate | 2019 |
| Clarendons South Coast Limited | Real estate | 1993 |