| Cardian Consulting Ltd | Professional & scientific | 2025 |
| Care Excel 247 Ltd | Health & social care | 2020 |
| Care Solutions Plus Ltd | Administrative & support | 2026 |
| Career Consultants Ltd | Administrative & support | 2024 |
| Career Wings Limited | Professional & scientific | 2025 |
| Careplus Pharma Limited | Wholesale & retail | 2024 |
| Careroots Ltd | Health & social care | 2022 |
| Carfy Limited | Transport & logistics | 2026 |
| Cargo Agriculture Limited | Transport & logistics | 2025 |
| Cargo Fresh Logistics Limited | Transport & logistics | 2014 |
| Cargo Gallery International Logistics Co Ltd | Transport & logistics | 2015 |
| Cargoexpert Hub Ltd | Transport & logistics | 2025 |
| Carlgert Ltd | Health & social care | 2022 |
| Caroline Lashbrook Design Ltd | Professional & scientific | 2013 |
| Carp Tackle Xchange Ltd | Wholesale & retail | 2020 |
| Carpenter SON Ltd | Construction | 2025 |
| Carpet World London Limited | Construction | 2014 |
| Cars Direct NOW Ltd | Wholesale & retail | 2021 |
| Cartier Graphics Limited | Manufacturing | 2008 |
| Carttogo Limited | Wholesale & retail | 2025 |
| Casa Essentials Ltd | Wholesale & retail | 2024 |
| Casa Radiance Limited | Real estate | 2024 |
| CASE4ALL Ltd | Wholesale & retail | 2019 |
| Caswan Services Limited | Information & communication | 2026 |
| Caviar Deck Limited | Wholesale & retail | 2021 |
| CC & Son's Consulting Private Limited | Other services | 2018 |
| CD Smart Builder Ltd | Construction | 2025 |
| Ceai House Ltd | Manufacturing | 2026 |
| Cell-Links Ltd | Wholesale & retail | 2005 |
| CENTAUR999 Ltd | Households | 2025 |
| Central Line Management Ltd | Administrative & support | 2023 |
| Centre for Spirituality and Cultural Advancement | Other services | 2009 |
| Certain Care Ltd | Health & social care | 2013 |
| Certain Enterprises Ltd | Financial services | 2017 |
| Certain Health Care Ltd | Administrative & support | 2022 |
| Certain Homes Ltd | Real estate | 2017 |
| Certainty 1 Ltd | Real estate | 2025 |
| Certainty Consulting Limited | Information & communication | 2014 |
| Cesb Health Care Limited | Health & social care | 2025 |
| Ceylon Bake House Ltd | Hospitality | 2017 |
| Ceylon Flavours Ltd | Hospitality | 2025 |
| CGR Businesses Ltd | Construction | 2005 |
| CGR Integrated Services Limited | Construction | 2003 |
| CGR Invest Ltd | Households | 2019 |
| CH Build Group Ltd | Construction | 2023 |
| Chacha'Z Limited | Hospitality | 2016 |
| Chalapati Ltd | Information & communication | 2023 |
| Challio Ltd | Real estate | 2026 |
| Chambali Wellness Ltd | Manufacturing | 2022 |
| Chamunda Arts Limited | Real estate | 2026 |
| Chance Delgado Ltd | Real estate | 2014 |
| Channeldoubler Ltd | Information & communication | 2021 |
| Chareebird Ltd | Wholesale & retail | 2022 |
| Chariot Cars Limited | Transport & logistics | 2022 |
| Charles Williams Groundworks Ltd | Construction | 2025 |
| Charlesdeb Services Limited | Health & social care | 2022 |
| Charlie Markham Props Ltd | Information & communication | 2023 |
| Charron Properties Ltd | Construction | 2022 |
| Chase International Computer Services Limited | Professional & scientific | 1984 |
| Chasvilla Company Limited | Transport & logistics | 2017 |
| Chateau Brocante Ltd | Wholesale & retail | 2019 |
| Chauhan Transport Limited | Transport & logistics | 2025 |
| Cheema Plumbing & Heating Ltd | Construction | 2023 |
| Chelsea and Fulham Cars.Uk. Limited | Administrative & support | 2006 |
| Chelsea Car Club Limited | Transport & logistics | 2024 |
| Chennai Biryani Ltd | Hospitality | 2022 |
| Chestnut Court Residents (Hounslow) Limited | Households | 1981 |
| Chhavion Technology Ltd | Information & communication | 2025 |
| Chhk Transport Ltd | Transport & logistics | 2026 |
| Chicoco London Ltd | Real estate | 2019 |
| Chini Company PTY Ltd | Wholesale & retail | 2023 |
| Chisel Construction Limited | Administrative & support | 2023 |
| Choice Trading Enterprises UK Ltd | Wholesale & retail | 2020 |
| Chombi Ltd | Construction | 2025 |
| Choose 1 Ltd | Administrative & support | 2024 |
| Chopra Driving School Limited | Education | 2023 |
| Chopra's Property Limited | Real estate | 2020 |
| CHR Homes Limited | Real estate | 2025 |
| Chrisember Support Limited | Administrative & support | 2023 |
| Christ Apostolic Church (Mount Zion) U.K Limited | Other services | 2012 |
| Christian Road Trans Ltd | Transport & logistics | 2026 |
| Christina Medical Services Ltd | Health & social care | 2012 |
| Churchill Financial Group Limited | Professional & scientific | 2024 |
| Churchill Management and Accounting Services Limited | Professional & scientific | 2021 |
| Churchill Real Estate Limited | Real estate | 2022 |
| Cianote Ltd | Education | 2025 |
| Cinera Ltd | Information & communication | 2018 |
| Cinnova Technologies Ltd | Wholesale & retail | 2025 |
| Ciocadau Construct Ltd | Construction | 2026 |
| Cipher Space Solutions Ltd | Information & communication | 2022 |
| Circus Group Asset Management Ltd | Wholesale & retail | 2022 |
| Cisco International Limited | Information & communication | 2008 |
| Cisco Systems Holdings UK Limited | Professional & scientific | 2012 |
| Cisco Systems Limited | Information & communication | 1990 |
| City & Southern Limited | Construction | 2014 |
| City & Southern Properties Limited | Real estate | 2003 |
| City Cars London Ltd | Transport & logistics | 2017 |
| City Flooring Europe Group Ltd | Construction | 2026 |
| City Parking Management Ltd | Information & communication | 2024 |
| City Tool Hire Limited | Administrative & support | 2011 |