| Central CAB Hire Limited | Extraterritorial | 2014 |
| Central Cafe & Restaurant Limited | Hospitality | 2018 |
| Ceocollection.Co Ltd | Wholesale & retail | 2022 |
| Cey's Catering Limited | Hospitality | 2020 |
| CFG Ltd | Wholesale & retail | 2025 |
| CGG Media Limited | Arts & recreation | 2016 |
| Champ One Ltd | Real estate | 2021 |
| Champion Construction Services Ltd | Construction | 2016 |
| Chan & Sons Healthcare Limited | Health & social care | 2009 |
| Changes (Morden) Limited | Other services | 2014 |
| Chappell Construction Limited | Construction | 2013 |
| Charisma Cabins Limited | Other services | 2000 |
| Charles Court Residents Group Limited | Households | 1989 |
| Charles FOX Management Limited | Real estate | 2006 |
| Charles Street Property Co Limited | Real estate | 2021 |
| Charlie PUD Ltd | Real estate | 2024 |
| Charming Ltd | Other services | 2016 |
| Chartwell IT Limited | Information & communication | 2009 |
| Chatsworth Lodge Residents Company Limited | Real estate | 2004 |
| Chebmain Limited | Real estate | 1977 |
| Checked Electric Ltd | Construction | 2019 |
| Cherrill Print Ltd | Manufacturing | 2011 |
| Cherubin Estates Limited | Real estate | 2007 |
| CHG Engineers Limited | Construction | 2025 |
| Chicago Grill Ltd | Hospitality | 2026 |
| Chicago Takeaway Ltd | Hospitality | 2024 |
| Chicken Kadai Ltd | Hospitality | 2026 |
| Chiffron Ltd | Financial services | 2009 |
| Chika Cana Ltd | Other services | 2023 |
| Chimex Holdings Ltd | Real estate | 2018 |
| Chiswick Builders Supplies Limited | Wholesale & retail | 1980 |
| Chivers Coaches Limited | Transport & logistics | 1982 |
| Choly Painting Limited | Construction | 2014 |
| Chopsy Daisy Limited | Hospitality | 2017 |
| Chris Carter-Pegg Ltd | Professional & scientific | 2015 |
| Chris Taylor Consulting Limited | Information & communication | 2016 |
| Christian Family Concern | Hospitality | 1980 |
| Christopher Talbot Ltd | Information & communication | 2023 |
| Chtr Ltd | Hospitality | 2024 |
| Chump Tools Limited | Wholesale & retail | 2024 |
| Church & Charity Accounts Service Ltd | Administrative & support | 2016 |
| Churchill Capital Investments Limited | Financial services | 2016 |
| Chynham Place Management Company Limited | Real estate | 2011 |
| Cikan Fastfood Limited | Hospitality | 2021 |
| Cilvia Ltd | Professional & scientific | 2024 |
| Cinco Amor Limited | Information & communication | 2014 |
| Cinematic Frame Ltd | Information & communication | 2024 |
| Cinik Properties Limited | Real estate | 2026 |
| CIT Associates Ltd | Information & communication | 1999 |
| Citrine Marine Services Ltd | Manufacturing | 2026 |
| City Stretch Limited | Other services | 2017 |
| City Tailor Exeter Ltd | Professional & scientific | 2024 |
| Civic Bridge Ventures Ltd | Construction | 2025 |
| CJ & PD Property Investments Limited | Real estate | 2021 |
| CJ Heating & Services Ltd | Construction | 2018 |
| Cjay Barbers Limited | Other services | 2019 |
| CKH Consulting Limited | Information & communication | 2008 |
| CLA Retail Group Ltd | Wholesale & retail | 2021 |
| Clan Aviation Ltd | Wholesale & retail | 2025 |
| Clapham Common Investment Ltd | Real estate | 2021 |
| Clapham Kebab Limited | Hospitality | 2025 |
| Claremont Fire Solutions Ltd | Professional & scientific | 2020 |
| Class of Cuts Limited | Other services | 2015 |
| CLC Estates Limited | Real estate | 2026 |
| Clean CUT Building Services Limited | Construction | 2012 |
| Clean CUT Fire Doors Ltd | Construction | 2022 |
| Cleaning Machine Ltd | Administrative & support | 2024 |
| Clearestate Probate Services Ltd | Construction | 2026 |
| Clearview Design & Build Ltd | Construction | 2025 |
| Clements Developments Limited | Professional & scientific | 2003 |
| Clements Investments Limited | Construction | 2003 |
| Clery Clinical Services Ltd | Health & social care | 2014 |
| Clientside Research Limited | Professional & scientific | 2013 |
| Cliso Properties Limited | Real estate | 2018 |
| Clocktower Cars London Ltd | Wholesale & retail | 2022 |
| Close Coach AI Ltd | Information & communication | 2025 |
| Cloudfoxy Ltd | Information & communication | 2019 |
| Cloudyinvest Ltd | Real estate | 2020 |
| Club Golf Limited | Professional & scientific | 2003 |
| CM Multi Trade Ltd | Construction | 2016 |
| Cmdental Limited | Health & social care | 2017 |
| Cmjp Ltd | Professional & scientific | 2021 |
| CMR Window Cleaning Ltd | Administrative & support | 2019 |
| Cmrental Limited | Real estate | 2025 |
| CNN Investments Limited | Real estate | 2019 |
| COA Properties Limited | Construction | 2022 |
| Coach Advancement Limited | Professional & scientific | 2011 |
| Coach HER UK CIC | Professional & scientific | 2025 |
| Coachee Network Ltd | Education | 2020 |
| Coachee Play Ltd | Arts & recreation | 2021 |
| Cobra Electronics Limited | Manufacturing | 1991 |
| Coco and NUT Coffee Limited | Wholesale & retail | 2019 |
| Coco and NUT Coffee London Ltd | Hospitality | 2022 |
| Coco and NUT Coffee Victoria Limited | Hospitality | 2021 |
| Coco and NUT Limpsfield Road Ltd | Hospitality | 2025 |
| Codehive Ltd | Education | 2023 |
| Coder of OZ Ltd | Information & communication | 2019 |
| Cogent Business Consulting Limited | Information & communication | 2018 |
| Colbrite Limited | Administrative & support | 2017 |
| Colin Joseph Law Ltd | Information & communication | 2024 |