| Classified Vintage Limited | Wholesale & retail | 2021 |
| Clay Hair Limited | Other services | 2009 |
| Clean Source Recruitment Ltd | Administrative & support | 2022 |
| Cleanone Ltd | Administrative & support | 2025 |
| Cleanou Ltd | Administrative & support | 2020 |
| Clear Capital Corporate Broking Ltd. | Financial services | 2020 |
| Clear Heights Ltd | Construction | 2021 |
| Clear Plumbing & Building Limited | Construction | 2015 |
| Clearfix Ltd | Information & communication | 2023 |
| Clearview Glazing Services LLP | | 2021 |
| Cleary Technical Services Limited | Construction | 2015 |
| Cleopatra Aesthetic and Cosmetic Centre Limited | Health & social care | 2018 |
| Cleverkit.Com Limited | Extraterritorial | 2013 |
| Cleves Court (Epsom) Management Limited | Households | 1998 |
| CLG London Ltd | Wholesale & retail | 2020 |
| Clician Store Ltd | Wholesale & retail | 2025 |
| Click IT Ltd | Manufacturing | 2025 |
| Clifton House Company Limited | Households | 1981 |
| Climbtop Limited | Arts & recreation | 2002 |
| Clinea Consulting Ltd | Professional & scientific | 2019 |
| Clipston Residents Company Limited | Households | 2013 |
| Clisham Consulting Ltd | Professional & scientific | 2023 |
| Close to the Edge Limited | Other services | 1987 |
| CLOSE2NATURE Film Ltd | Arts & recreation | 2023 |
| Closed WON Limited | Information & communication | 2012 |
| Closiant Limited | Professional & scientific | 2013 |
| Cloud 9 Cycles Limited | Manufacturing | 1999 |
| Clove Infrastructure Management Services Ltd | Professional & scientific | 2017 |
| Clover RTM Company Ltd | Households | 2008 |
| CLP London Limited | Hospitality | 2022 |
| CLR Recording Company Ltd | Information & communication | 2025 |
| CLS Consultancy Ltd | Administrative & support | 2024 |
| Club Executive Cars Ltd | Transport & logistics | 2026 |
| Club Twenty Two Ltd | Arts & recreation | 2024 |
| Club Vale Limited | Education | 2012 |
| Clue Adventures Limited | Other services | 2016 |
| Clythe Management Limited | Real estate | 2013 |
| CM Decor Ltd | Construction | 2007 |
| CM MUK Ltd | Real estate | 2017 |
| CMB Motor Services Limited | Wholesale & retail | 1995 |
| Cmdrn Engineering Limited | Professional & scientific | 2015 |
| CMG Systems Ltd | Information & communication | 2026 |
| CMN Sense Ltd | Information & communication | 2025 |
| CMS Services Ltd | Hospitality | 2023 |
| Cmyk Print Limited | Extraterritorial | 2025 |
| CNE Taxi Logistics Ltd | Transport & logistics | 2022 |
| CNI Insights Limited | Professional & scientific | 2025 |
| CNJ Events Ltd | Hospitality | 2021 |
| Cnmc Limited | Information & communication | 2015 |
| Co-Ownership Solutions LLP | | 2011 |
| Coach House Holdings Ltd | Real estate | 2015 |
| Coach House Solutions Limited | Other services | 2024 |
| Coaches Corner Ltd | Education | 2023 |
| Coaching in Business Limited | Administrative & support | 2014 |
| Coastal Media Ltd | Professional & scientific | 2023 |
| Cobham Football and Social Club | Arts & recreation | 2022 |
| Cobham Trailer Hire Limited | Administrative & support | 2021 |
| Cobra Corporate Services Limited | Other services | 2001 |
| Coco Management Ltd | Construction | 2025 |
| Cocoa Treasures Ltd | Wholesale & retail | 2020 |
| Codeinedreams Ltd | Wholesale & retail | 2025 |
| Codeitech Ltd | Administrative & support | 2020 |
| Codemesh Ltd | Information & communication | 2018 |
| Coders Beyond Borders Limited | Information & communication | 2015 |
| Codes House Management Company Limited | Households | 2022 |
| Coffee MAD Limited | Hospitality | 2016 |
| COG Design Limited | Professional & scientific | 1994 |
| Cogalot Limited | Real estate | 2004 |
| Cogs Management Services Limited | Extraterritorial | 1992 |
| Coherent Security Ltd | Information & communication | 2021 |
| Colab Floor Ltd | Construction | 2025 |
| Colabcom Limited | Information & communication | 2011 |
| Cole Turner Associates Limited | Professional & scientific | 2016 |
| Collabera International Limited | Wholesale & retail | 2024 |
| Collar and Comb Grooming Limited | Other services | 2018 |
| Collec Ciel Ltd | Wholesale & retail | 2018 |
| College Court (Mitcham) Management Limited | Households | 1989 |
| College Fields Management Company Limited | Real estate | 1989 |
| College Gate Properties Limited | Real estate | 2022 |
| Collina Rose Homes Ltd | Real estate | 2015 |
| Colloco Financial Limited | Financial services | 2013 |
| Colman Advisory Ltd | Professional & scientific | 2025 |
| Colombo Kitchen Ltd | Hospitality | 2023 |
| Colony Homes Limited | Real estate | 2000 |
| Colossus Productions (London) Limited | Professional & scientific | 2021 |
| Colour Negative Limited | Information & communication | 2025 |
| Columbus Consulting Ltd | Administrative & support | 2009 |
| Colven Ltd | Professional & scientific | 2025 |
| Colville Search Limited | Professional & scientific | 2023 |
| Colwall Court Management Limited | Households | 2009 |
| Colwick Hall Hotel Limited | Hospitality | 2009 |
| Combelle Ltd | Professional & scientific | 2022 |
| Combes Communications Limited | Information & communication | 2019 |
| Comma Secured Ltd | Administrative & support | 2019 |
| Command Security Systems Ltd | Administrative & support | 2024 |
| Commercial Drawing Service Ltd. | Professional & scientific | 1995 |
| Commercial Driver Training Limited | Administrative & support | 2018 |
| Community Clean Epsom Ltd | Administrative & support | 2021 |
| Community Cricket C.I.C. | Arts & recreation | 2019 |
| Companies in Balance Ltd | Professional & scientific | 2019 |