| Cedar Consultancy Limited | Professional & scientific | 1994 |
| Cedar Wave Shipping Ltd | Transport & logistics | 2025 |
| Cemcon Ltd | Construction | 2005 |
| Center for Higher Insights Limited | Professional & scientific | 2013 |
| Central Casting International Limited | Arts & recreation | 2018 |
| Central Casting Limited | Arts & recreation | 2002 |
| Central Collections (Northern) Limited | Arts & recreation | 1989 |
| Central Dental Limited | Health & social care | 2006 |
| Central Express Cars Limited | Transport & logistics | 2010 |
| Central G.C.E. Tutorials Limited | | 1977 |
| Centralheat Limited | Wholesale & retail | 1998 |
| Centre 4 Learning Ltd | Professional & scientific | 2003 |
| Centrepoint Building Services Limited | Construction | 2002 |
| Century Emporium (Broadway) Limited | Real estate | 1978 |
| Century Properties Estate Agents Limited | Real estate | 2003 |
| Cerama Limited | Professional & scientific | 2007 |
| Cerberus Networks Limited | Information & communication | 2006 |
| CES Eco Park Holdings Limited | Water & waste | 2025 |
| CEW Design Ltd | Arts & recreation | 2012 |
| CFD Carpentry Limited | Construction | 2004 |
| CFV Holdings Ltd | Professional & scientific | 2011 |
| CGC Design & Build Ltd. | Construction | 2002 |
| Chambers Property Partnership LLP | | 2021 |
| Chana Properties Ltd | Real estate | 2014 |
| Change Delivery Partners Ltd | Professional & scientific | 2004 |
| Channel North-Africa Broadcasting TV Ltd | Information & communication | 2024 |
| Chapel Orchard Ltd | Hospitality | 2025 |
| Chaplin House Hotel Limited | Hospitality | 2001 |
| Chaplins Entertainment Ltd | Arts & recreation | 2001 |
| Chaplins N C Limited | Arts & recreation | 2012 |
| Chaplins Theatre Productions Limited | Arts & recreation | 1995 |
| Chapman Associates (CA) Limited | Professional & scientific | 2003 |
| Chapter Two Consultants Ltd | Administrative & support | 2024 |
| Chargemaster Limited | Manufacturing | 2008 |
| Charles Dobie Limited | Construction | 2002 |
| Charles Greenwood Consulting Ltd | Professional & scientific | 2011 |
| Charles Stuart Autos Limited | Wholesale & retail | 1987 |
| Charles Waldorf Limited | Administrative & support | 2017 |
| Chart Inter Limited | Wholesale & retail | 2003 |
| Charter Green Accountants Ltd | Professional & scientific | 2003 |
| Chatoo & SON Limited | Wholesale & retail | 1993 |
| Chawla's Limited | Real estate | 2002 |
| Check and Balance Limited | Administrative & support | 2010 |
| Cheerglow Limited | Wholesale & retail | 1981 |
| Chefsecret Ltd | Hospitality | 2016 |
| Chehal Properties Ltd | Real estate | 2007 |
| Chemputrix Limited | Administrative & support | 1997 |
| Cherilmain Limited | | 1979 |
| Chesham Concepts Ltd | Construction | 2017 |
| Chesnut ROW Management Company Limited | Real estate | 1993 |
| Chester ROW Construction Ltd | Construction | 2021 |
| Chesterton Consultancy Ltd | Professional & scientific | 2002 |
| Chestnut Estates Limited | Real estate | 1972 |
| Chibton Services Limited | Transport & logistics | 2020 |
| Chichester Court (South Harrow) Freehold Limited | Households | 2009 |
| Chichester Court (South Harrow) Management Limited | Households | 1988 |
| Chicken Cabins Limited | Hospitality | 1965 |
| Chicken World Ltd | Hospitality | 2002 |
| Chidakash Solution Ltd | Information & communication | 2018 |
| Chigwell Management Company Limited | Households | 1997 |
| Chilham Close Residents Association Limited | Households | 2016 |
| Chimera Design & Build Ltd | Professional & scientific | 2007 |
| China Fashion & Textile U.K. Ltd | Wholesale & retail | 2002 |
| Chipmark Limited | Professional & scientific | 1986 |
| Chipz Limited | Hospitality | 2023 |
| Chithi Vinayagar (UK) Limited | Real estate | 2006 |
| Choice Corner Ltd | Wholesale & retail | 2025 |
| Choice Mobile Communications Ltd | Real estate | 1997 |
| Chopra Mortgage Services Limited | Financial services | 1998 |
| Chorleywood Retail Limited | Real estate | 2005 |
| Chorusline Limited | Wholesale & retail | 1985 |
| Chris Church Ltd | Arts & recreation | 2015 |
| Chris Kenny Limited | Arts & recreation | 2002 |
| Christopher Nevill Lettings Ltd | Real estate | 1995 |
| Christopher. Conlon | | 1999 |
| Christy & Sons Ltd | Real estate | 2015 |
| Church Grove Property Ltd | Real estate | 2023 |
| Churchills Estate Planning Limited | Professional & scientific | 2003 |
| Cienega Limited | Education | 2006 |
| CIL UK Holdings Limited | Financial services | 2019 |
| Cine INK Limited | Information & communication | 2008 |
| Cinebees Media (UK) Limited | Information & communication | 2022 |
| Circle Court (Wembley) Management Company Limited | Professional & scientific | 1961 |
| Circle Transport Warehousing and Packing Limited | | 1980 |
| Circular Developments Limited | Information & communication | 1995 |
| City Business Enterprises Limited | Real estate | 2000 |
| City Commerce (UK) Ltd | Other services | 2001 |
| City Financial Administration Limited | Administrative & support | 1970 |
| City Financial Asset Management Limited | Financial services | 1973 |
| Citygate Automotive Limited | Wholesale & retail | 2005 |
| Citygate Holdings Limited | Professional & scientific | 2005 |
| Citygate Investment Management Limited | Real estate | 2006 |
| Citygate TPS LLP | | 2007 |
| Clairhaven Estates Ltd | Real estate | 2025 |
| Clantech Limited | | 1977 |
| Claremont Cattery Limited | Other services | 2004 |
| Claremont Road Management Company Limited | Extraterritorial | 2002 |
| Clarity Investment and Finance Limited | Financial services | 2024 |
| Clarkwell Associates Ltd | Professional & scientific | 1999 |
| Classic Cars (UK) Limited | Wholesale & retail | 2002 |