| CVD Admin Services Ltd | Administrative & support | 2024 |
| CVG Services Ltd | Construction | 2021 |
| CW Data Installs Ltd | Professional & scientific | 2021 |
| CW Property Maintenance Ltd | Households | 2025 |
| CWS Carpentry Ltd | Construction | 2026 |
| CX Experts Global Ltd | Wholesale & retail | 2022 |
| CX Media Solutions Ltd | Professional & scientific | 2025 |
| CXO Selection Limited | Administrative & support | 2017 |
| Cyanbridge Limited | Financial services | 2019 |
| Cyber Industries Limited | Information & communication | 2021 |
| Cyclegam Ltd | Wholesale & retail | 2025 |
| Cyclical PM Ltd | Construction | 2022 |
| Cyclops Beer Limited | Other services | 2010 |
| Cydney Hill Sports Therapy Limited | Health & social care | 2020 |
| Cynodont Limited | Administrative & support | 2023 |
| Cypography JV Ltd | Professional & scientific | 2022 |
| Cypography Ltd | Professional & scientific | 2017 |
| Cypography OG Ltd | Professional & scientific | 2023 |
| Cyprus Fish and Chips Ltd | Hospitality | 2025 |
| Cyramo Limited | Health & social care | 2022 |
| Cyril J.Deal Limited | Wholesale & retail | 1947 |
| Cyrusplace Limited | Real estate | 2019 |
| D & a Plumbing (Colchester) Ltd | Construction | 2021 |
| D & D Vehicle Solutions Ltd | Wholesale & retail | 2019 |
| D & I Engineering (Ipswich) Limited | Manufacturing | 2005 |
| D & J Gifts Ltd | Wholesale & retail | 2026 |
| D & N Property East Anglia Ltd | Real estate | 2014 |
| D & S Auto Sales Ltd | Wholesale & retail | 2017 |
| D a C Group Limited | Professional & scientific | 2007 |
| D a Fisher Motors Limited | Wholesale & retail | 2008 |
| D a Page Landscape and Fencing Limited | Administrative & support | 2020 |
| D Austin Property Limited | Real estate | 2024 |
| D B Kirkham Limited | Professional & scientific | 2009 |
| D Babbs & Sons Ltd | Construction | 2026 |
| D Bear Security Limited | Administrative & support | 2023 |
| D Blake Electrical Services Limited | Construction | 2009 |
| D Bruce Developments Ltd | Construction | 2015 |
| D C Heating and Plumbing Ltd | Construction | 2021 |
| D Cable Roofing Ltd | Construction | 2012 |
| D Clark Consultancy Limited | Other services | 2011 |
| D Curtis and Sons Ltd | Construction | 2026 |
| D F Alresford Limited | Wholesale & retail | 2021 |
| D F Homes Limited | Construction | 2004 |
| D G P Building & Renovations Ltd | Construction | 2009 |
| D G Property Invest Limited | Extraterritorial | 2024 |
| D G Rose Holdings Limited | Financial services | 2026 |
| D GEE Consulting Limited | Professional & scientific | 2022 |
| D Hall Electrical Ltd | Construction | 2017 |
| D Hall Investments Limited | Real estate | 2023 |
| D Harvey Fire Ltd | Construction | 2022 |
| D IT Solutions Ltd | Information & communication | 2008 |
| D J Baker & Sons Contracts Ltd | Construction | 2018 |
| D J Bewers Carpentry Limited | Construction | 2009 |
| D J Deadman Limited | Construction | 2003 |
| D J King Sealant Applicators Ltd | Administrative & support | 2014 |
| D J Utilities Limited | Construction | 2010 |
| D J W Plumbing Ltd | Construction | 2017 |
| D King Decorating Ltd | Construction | 2019 |
| D Knight Landscapes Limited | Administrative & support | 2025 |
| D N a Courses Ltd | Education | 2018 |
| D N Woods Ltd | Administrative & support | 2014 |
| D O'Hare Construction Limited | Construction | 2015 |
| D Pittock Engineering Limited | Construction | 2006 |
| D S Essex Limited | Health & social care | 2019 |
| D Stevenson Caravans Ltd | Wholesale & retail | 2023 |
| D Village Kitchen Ltd | Hospitality | 2022 |
| D Woods Cleaning Ltd | Administrative & support | 2005 |
| D&A Photography Ltd | Professional & scientific | 2014 |
| D&B Bar Ltd | Hospitality | 2023 |
| D&D Skyline Ltd | Other services | 2019 |
| D&I Construction Services Ltd | Construction | 2019 |
| D&J Project Management Ltd | Construction | 2019 |
| D&M Men's Grooming Ltd | Other services | 2023 |
| D&P Ltd | Health & social care | 2015 |
| D&S Real Estate Essex Ltd | Real estate | 2021 |
| D&V Group Ltd | Hospitality | 2025 |
| D'Lights Event Catering Limited | Hospitality | 2016 |
| D'Silva Transport Solutions Ltd | Administrative & support | 2011 |
| D'Stassi Art Limited | Wholesale & retail | 2017 |
| D-Med Consultancy Limited | Professional & scientific | 2023 |
| D. Byford & Sons (Nurseries) Limited | Real estate | 1969 |
| D. C. White Industrial Machinery Limited | Wholesale & retail | 1986 |
| D.A. Cant Ltd. | Construction | 1998 |
| D.A. Carpentry & Construction Improvements Ltd | Manufacturing | 2019 |
| D.A.Morley (Roofing Contractor) Ltd | Construction | 2011 |
| D.A.S. Professional Services Limited | Administrative & support | 2013 |
| D.B.S.Builders Limited | Construction | 1988 |
| D.G. Rose Limited | Construction | 1996 |
| D.J. Barton Associates Limited | Construction | 1994 |
| D.L.R Decor Ltd | Construction | 2026 |
| D.R Locks Locksmiths Ltd | Other services | 2025 |
| D1RECRUITMENT Limited | Administrative & support | 2025 |
| D2M2 Kizims Ltd | Real estate | 2025 |
| D2P Online Ltd | Wholesale & retail | 2024 |
| D3 Media Limited | Information & communication | 2003 |
| DAA Tax Consulting Limited | Professional & scientific | 2016 |
| Daam Services Ltd | Construction | 2017 |
| DAB Pumps Limited | Wholesale & retail | 1978 |
| DAC Contracting Limited | Construction | 2003 |
| DAC Wholesale Flooring Limited | Wholesale & retail | 2011 |