| Chalfont Capital Limited | Professional & scientific | 2005 |
| Chalfont Common Foodfayre Ltd | Wholesale & retail | 2006 |
| Chalfont Investment Consultants Limited | Financial services | 1994 |
| Champagne Flights (Southern) Ltd | Arts & recreation | 2003 |
| Chandos Services Ltd | Professional & scientific | 1992 |
| Chartridge Scientific Computing Services Ltd | Information & communication | 1999 |
| Chase Mill Limited | Real estate | 2022 |
| Chattah Enterprises Ltd | Information & communication | 2025 |
| Chazar Ltd | Health & social care | 2025 |
| Chelsea Wharf Management Company Limited | Real estate | 2005 |
| Chequers Roofing Limited | Construction | 2003 |
| Chesham Osteopathic Clinic Limited | Health & social care | 2003 |
| Chez Yasser Limited | Hospitality | 2018 |
| Childs Services Ltd. | Construction | 1999 |
| Chiltern Care Chairs Limited | Wholesale & retail | 1999 |
| Chiltern Domestic Servicing Limited | Wholesale & retail | 1982 |
| Chiltern Water Management Limited | Professional & scientific | 2005 |
| Chough Media Ltd. | Professional & scientific | 2004 |
| Choules & Co. Limited | Professional & scientific | 1994 |
| Chris Flint Limited | Construction | 2002 |
| Chris Price Limited | Construction | 2002 |
| Church Garage Limited | Wholesale & retail | 2003 |
| Cityline Consultants Limited | Administrative & support | 1990 |
| CJ Associates Training Limited | Public administration | 2003 |
| Clare Jarvis Mortgage Specialist Ltd | Financial services | 2019 |
| Classic Car Racing Limited | Arts & recreation | 1997 |
| Clausebase Limited | Real estate | 1999 |
| Clawbloomcraft Ltd | Wholesale & retail | 2025 |
| Clawtidejewels Ltd | Wholesale & retail | 2025 |
| Claydon Court Residents Company Limited | Other services | 1973 |
| Cleanland Limited | Real estate | 1991 |
| Clear Innovations Limited | Professional & scientific | 2007 |
| Cleverly Done Limited | Professional & scientific | 2008 |
| Clipper Components Limited | Manufacturing | 1985 |
| Cloverdown Associates Limited | Professional & scientific | 2000 |
| Cloverleaf Technology Limited | Information & communication | 1998 |
| CMB JB Ltd | Manufacturing | 2003 |
| CMS Corporate Mailing Solutions Limited | Professional & scientific | 1998 |
| Cognisco Holdings Limited | Information & communication | 2017 |
| Cole Opus Limited | Professional & scientific | 2011 |
| Collingwood Management Limited | Professional & scientific | 1991 |
| Connaught Groundworks Limited | Administrative & support | 2001 |
| Contrai Limited | Professional & scientific | 2024 |
| Coralsparkjewels Ltd | Wholesale & retail | 2025 |
| Coralwispart Ltd | Wholesale & retail | 2025 |
| Cornucopia Designs Ltd | Wholesale & retail | 1994 |
| Corporate International Spedition Limited | Transport & logistics | 1991 |
| Corvus Enterprises Limited | Professional & scientific | 2000 |
| Cositas Limited | Wholesale & retail | 2016 |
| Covenant (UK) Ltd | Real estate | 2005 |
| Coyy Ltd | Administrative & support | 2025 |
| CPM Mould Solutions Limited | Manufacturing | 2004 |
| Crack-A-Tax Limited | Professional & scientific | 2003 |
| Creating Limited | Professional & scientific | 1999 |
| Creation Workshops Limited | Manufacturing | 2002 |
| Crocketts Gates Ltd | Manufacturing | 2005 |
| Crowhurst Associates Limited | Professional & scientific | 2002 |
| Crown Properties D & S Limited | Real estate | 2023 |
| Crownhill Consulting Ltd | Professional & scientific | 2002 |
| Cultural Zest Limited | Professional & scientific | 2025 |
| D N R Hair Designs Limited | Other services | 2005 |
| D&H Associates Limited | Professional & scientific | 2007 |
| D.A. Smyth Limited | Administrative & support | 2002 |
| D.D.S. Associates Limited | Professional & scientific | 1990 |
| D.W.Burns & Partner Limited | Wholesale & retail | 1963 |
| Damsolve Limited | Professional & scientific | 2010 |
| Darvell Drive 3036 RTE Company Limited | Households | 2003 |
| Databell Computing Limited | Information & communication | 1997 |
| Databrief Publications Limited | | 1979 |
| Davies Building Co (Bucks) Ltd | Construction | 2007 |
| Dawsonrentals Finance Limited | Extraterritorial | 2007 |
| DC Ginger Limited | Extraterritorial | 2005 |
| Dd-Ventures Limited | Information & communication | 2004 |
| Deadline Couriers Limited | Extraterritorial | 1997 |
| Deadline Despatch Limited | Transport & logistics | 1980 |
| Deadline Express (UK) Limited | Extraterritorial | 1997 |
| Deadline Express Deliveries Limited | Extraterritorial | 1997 |
| Deadline Group Limited | Extraterritorial | 1984 |
| Deadline International Limited | Extraterritorial | 1999 |
| Deadline Next Day Limited | Extraterritorial | 1997 |
| Deadline Overnight Limited | Professional & scientific | 1990 |
| Deadline Same Day Limited | Extraterritorial | 1997 |
| Deadline Worldwide Limited | Extraterritorial | 1984 |
| Delworth Enterprises Limited | Real estate | 2005 |
| Despatch Deadlines Limited | Extraterritorial | 1997 |
| Development Edge Limited | Professional & scientific | 2005 |
| Devlon Limited | Construction | 1997 |
| Dhanvikapandi Limited | Professional & scientific | 2024 |
| Dibbo Limited | Manufacturing | 2000 |
| Digi-World International Ltd | Information & communication | 2020 |
| Diva Link Limited | Information & communication | 2001 |
| DLA Architects Practice Limited | Professional & scientific | 2001 |
| DO Advisory Group Ltd | Hospitality | 2026 |
| Domainscanners Limited | Information & communication | 2005 |
| Domglade Limited | Manufacturing | 1997 |
| Dougfield Plumbers Supplies Limited | Wholesale & retail | 1993 |
| Dove Marketing Limited | Transport & logistics | 1994 |
| DS Displays Limited | Manufacturing | 2014 |
| Dssonance Ltd | Information & communication | 2024 |
| Dukes Kiln Cottages Limited | Hospitality | 2001 |