| Checkley Group Holdings Ltd | Financial services | 2024 |
| Cheshire Relocation Limited | Real estate | 1999 |
| Chessworth Limited | Wholesale & retail | 2020 |
| Chill Investment Limited | Real estate | 2021 |
| Chris Campbell Estate Agents (Battle) Limited | Real estate | 2008 |
| Chrono Global Ltd | Wholesale & retail | 2020 |
| Cibus Waste Limited | Water & waste | 2019 |
| Civic House Ltd | Information & communication | 2004 |
| CJ Alliance Ltd | Real estate | 2018 |
| Cjoy Psychotherapy Limited | Health & social care | 2022 |
| Clarity Stores Ltd | Wholesale & retail | 2020 |
| Clear CUT Property Limited | Real estate | 1998 |
| Clearwater (Hellingly) Limited | Construction | 2019 |
| Clearwater Land and New Homes (Newtown) Limited | Construction | 2011 |
| Clearwater Land and New Homes Limited | Construction | 2006 |
| Cleenwater Limited | Water & waste | 2006 |
| Cliffe Leas Management Limited | Households | 1989 |
| Clive Vale Nursery ORE Ltd | Real estate | 2025 |
| Clive Vale Property Holdings Ltd | Real estate | 2025 |
| Colin Beesting Consulting Limited | Professional & scientific | 2010 |
| Collings Research Limited | Information & communication | 2004 |
| Commonside Management Services Limited | Information & communication | 1987 |
| Consultancy LA Limited | Financial services | 2015 |
| Copper Leaf Media Ltd | Professional & scientific | 2017 |
| Corinne Davey Development Consultancy (Cddc) Limited | Professional & scientific | 2008 |
| Corporate Finance U.K. Limited | Real estate | 1997 |
| Corporate Management Services (S.E.) Limited | Financial services | 1986 |
| Cortex Investments Ltd | Real estate | 2021 |
| Cotrinity Ltd | Professional & scientific | 2020 |
| Counterculture Partnership LLP | | 2011 |
| Counterpoint Communications Limited | Information & communication | 2003 |
| Coussens (Haulage) Limited | Extraterritorial | 2006 |
| Coussens Cranes Limited | Administrative & support | 2011 |
| Coussens of Bexhill Limited | Construction | 2001 |
| Crabtree Property Maintenance Limited | Construction | 2008 |
| Creo Developments Ltd | Construction | 2019 |
| Crocs (Stocchetti) Ltd | Financial services | 2025 |
| CRS Media Technology Limited | Manufacturing | 2003 |
| Crump Winter Limited | Administrative & support | 1998 |
| CSR2 Property Management LLP | | 2021 |
| Ctre Ltd | Real estate | 2002 |
| Ctrl ALT Delete Limited | Information & communication | 1998 |
| Cullen Electrical Contractors Limited | Construction | 2011 |
| Cura Flex Ltd | Wholesale & retail | 2024 |
| CUT IT OUT Limited | Professional & scientific | 2006 |
| D & a Simes Plumbing and Heating Ltd | Construction | 2018 |
| D & K Estates Limited | Real estate | 2011 |
| D a French Carpentry Limited | Construction | 2004 |
| D F Thorne Electrical Contractor Limited | Construction | 2003 |
| D Holdaway Consulting Limited | Administrative & support | 2007 |
| D M O'Brien Ltd | Professional & scientific | 2019 |
| D Medical Limited | Professional & scientific | 2014 |
| D R Hastings Electrical Limited | Construction | 2011 |
| D.C. Coachworks Limited | Wholesale & retail | 2004 |
| DAN Baldwin Limited | Arts & recreation | 2007 |
| Dare Reigate Limited | Arts & recreation | 2014 |
| Daskalakis Property Ltd | Real estate | 2018 |
| Data Systems & Technologies LLP | | 2023 |
| Dataflow Event Operations LLP | | 2013 |
| David Bishop Construction Ltd | Construction | 2019 |
| David Wartnaby Limited | Information & communication | 2005 |
| David White SET Design Limited | Arts & recreation | 2013 |
| Davison Oxley Homes Limited | Construction | 2015 |
| Davison Oxley Limited | Real estate | 2020 |
| DCG Architecture Limited | Professional & scientific | 2008 |
| Decimus Ltd | Construction | 2021 |
| Decimus Properties Ltd | Real estate | 2022 |
| Dennett & Starr Developments Limited | Real estate | 1998 |
| Designer Surfaces Products Limited | Wholesale & retail | 2012 |
| Devaux Estates Investment Ltd | Real estate | 2021 |
| Devaux Estates Property Management LLP | | 2021 |
| Devonshire Square Ltd | Real estate | 2021 |
| Diamond Bridge Holdings Ltd | Real estate | 2014 |
| Diamond Management Services LLP | | 2005 |
| Digital Union Limited | Information & communication | 2025 |
| DJ Business Consulting Ltd | Professional & scientific | 2025 |
| DKN Estates Ltd | Real estate | 2016 |
| DMK Catering (T/A Pissarro's Brasserie) Limited | Hospitality | 2017 |
| DML Investments Ltd | Real estate | 2018 |
| Dogtemple Consulting Limited | Information & communication | 2005 |
| Doig Project Management Limited | Construction | 2017 |
| Dollyrose Property LLP | | 2017 |
| Domaines Estates Limited | Real estate | 2009 |
| Donemay Limited | Real estate | 2025 |
| Dorchester (Fifth) Management Company Limited | Households | 1982 |
| Downland Building Services Limited | Construction | 1994 |
| DPM Tenant Management Ltd | Real estate | 2025 |
| DPS Tenant Management LLP | | 2021 |
| DRM Stark Investment Limited | Real estate | 2021 |
| DRM Stark Property Management Limited | Real estate | 2024 |
| DRN Ventures Limited | Financial services | 2015 |
| DU Cros House Management Limited | Households | 2008 |
| Ductwork by Design Limited | Manufacturing | 1996 |
| Dunne Property LLP | | 2018 |
| Dutch Design Studio UK Limited | Other services | 2014 |
| Dynamix Properties LLP | | 2023 |
| E & M Development (Essex) Ltd | Construction | 2016 |
| Eagle Vision (London) Limited | Real estate | 2002 |
| Eaglewealth LLP | | 2016 |
| Eaglewealth Property Development Ltd | Real estate | 2016 |