| Cyberce Limited | Information & communication | 2021 |
| Cyclist Corps Limited | Hospitality | 2016 |
| Cylra Limited | Information & communication | 2025 |
| Cysec Global Ltd | Professional & scientific | 2026 |
| D a Locum Ltd | Professional & scientific | 2019 |
| D Allen's Fresh Fish Sales Ltd | Wholesale & retail | 2008 |
| D B Air Solutions Ltd | Construction | 2017 |
| D Baster Haulage Ltd | Transport & logistics | 2018 |
| D Berry Information & Security Management Consultants Limited | Professional & scientific | 2021 |
| D Grafen & Sons Ltd | Agriculture & fishing | 2017 |
| D Howard Consulting Limited | Professional & scientific | 2024 |
| D J Kiddy Limited | Agriculture & fishing | 2012 |
| D J Slater Limited | Construction | 2012 |
| D Silvestri Future Limited | Wholesale & retail | 2025 |
| D W Civil Engineers Limited | Construction | 2015 |
| D. Bronson | | 1988 |
| D.H. Steed Farms | Agriculture & fishing | 1965 |
| D.J. Goode & Associates Limited | Professional & scientific | 2002 |
| D.P.Nott & Sons Limited | Agriculture & fishing | 1958 |
| D.S Auto Suffolk Ltd | Professional & scientific | 2025 |
| D.W. Plant Hire Ltd | Administrative & support | 2008 |
| D1G Limited | Real estate | 2004 |
| Dachshunds & Doodles Limited | Agriculture & fishing | 2025 |
| DAG Logistics Limited | Transport & logistics | 2010 |
| Dallmer Limited | Wholesale & retail | 1996 |
| DAN Martin Properties Limited | Households | 2026 |
| Dann & Kaye Limited | Health & social care | 2020 |
| Dantzic Group Ltd | Other services | 2021 |
| Daro Group Limited | Administrative & support | 2008 |
| Daro Manufacturing Services Limited | Manufacturing | 2000 |
| Daro Specialist Lighting Limited | Administrative & support | 2020 |
| Daro UV Systems Limited | Manufacturing | 2007 |
| Data Compliant Limited | Professional & scientific | 2014 |
| Dave Osborne Ltd | Professional & scientific | 2019 |
| Dave Preset Ltd | Information & communication | 2019 |
| David Barber Dental Technology Limited | Health & social care | 2011 |
| David Bond Ltd. | Transport & logistics | 2011 |
| David Burr (Bury ST Edmunds) Limited | Real estate | 2023 |
| David Burr (Castle Hedingham) Limited | Real estate | 2006 |
| David Burr (Clare) Limited | Real estate | 2006 |
| David Burr (Holiday Lets) Ltd | Real estate | 2022 |
| David Burr (Leavenheath) Limited | Real estate | 2015 |
| David Burr (Long Melford) Limited | Real estate | 2003 |
| David Burr (Newmarket) Limited | Real estate | 2022 |
| David Burr (Woolpit) Limited | Real estate | 2003 |
| David Burr Estate Agency Co. Ltd | Professional & scientific | 2020 |
| Davidseo Limited | Professional & scientific | 2025 |
| Davies Consulting Solutions Ltd | Professional & scientific | 2018 |
| Day & Brown Brickwork Ltd | Construction | 2022 |
| Day and Thompson Limited | Construction | 2008 |
| Daybridge Limited | Transport & logistics | 2008 |
| DCJ Properties Limited | Real estate | 2010 |
| DE Vere Consulting Ltd | Professional & scientific | 2020 |
| DE Vere Fabrics Limited | Manufacturing | 1994 |
| Deacons Close Management Limited | Households | 1998 |
| Dean JAY Pearce Architectural Design & Planning Ltd | Professional & scientific | 2014 |
| Dedham Vale Chimney Sweeps Ltd | Administrative & support | 2025 |
| Deepside Consulting Limited | Information & communication | 2014 |
| Defender Falcons UK Limited | Agriculture & fishing | 2025 |
| Defiantly Different Clothing Company Limited | Wholesale & retail | 2021 |
| Demitasse Limited | Manufacturing | 2004 |
| Denton Arts Limited | Arts & recreation | 2009 |
| Derma Clinic Aesthetics Limited | Other services | 2022 |
| Derryville Limited | Real estate | 1979 |
| Design Tech Solutions Ltd | Professional & scientific | 2022 |
| Deskmate Technologies Limited | Information & communication | 2018 |
| Destination Moreves Ltd | Hospitality | 2026 |
| Deutscher Anwaltverein in Grossbritannien Limited | Professional & scientific | 2004 |
| Devability Ltd | Information & communication | 2016 |
| Devereux Roofing Services Limited | Construction | 2007 |
| DG Machine & Plant Hire Limited | Administrative & support | 2019 |
| DGA Engineering and Testing Ltd | Professional & scientific | 2021 |
| DGC Electrical (Suffolk) Limited | Construction | 2020 |
| DH Pharmacy Limited | Wholesale & retail | 2025 |
| Didi Stores Limited | Wholesale & retail | 2021 |
| Digiclerk Ltd | Information & communication | 2019 |
| Digital Health Advisory Ltd | Professional & scientific | 2018 |
| Dilato Technology Ltd | Wholesale & retail | 2017 |
| Dimension Stoves and Stone Ltd | Professional & scientific | 2008 |
| Dinky Treats Ltd | Wholesale & retail | 2023 |
| Direct Management Training Limited | Education | 2011 |
| Diversity X Ltd | Financial services | 2021 |
| DJJ Consultants (East Anglia) Limited | Professional & scientific | 2010 |
| DK Brickwork (Sudbury) Limited | Construction | 2016 |
| DMA Property Services Limited | Construction | 2018 |
| DMH Wines Limited | Manufacturing | 2021 |
| DMW Window Cleaning Services Limited | Households | 2010 |
| Dnps Building Contractors Limited | Construction | 2010 |
| Dome Engineering Design Ltd | Professional & scientific | 2011 |
| Domestic Appliances (Sudbury) Limited | Wholesale & retail | 2003 |
| Donthorn Mill Property Limited | Households | 2020 |
| Doolan Beckett Limited | Real estate | 2019 |
| Dotty and Belle Ltd | Manufacturing | 2022 |
| Double SIX Enterprise Limited | Extraterritorial | 2014 |
| Dove Creative Limited | Professional & scientific | 2012 |
| Dovecote Gardens Residents Association Limited | Households | 1991 |
| DPC Building Services Ltd | Construction | 2017 |
| DPH Carpentry & Maintenance Limited | Construction | 2014 |
| DR. Redmond Tutoring Limited | Education | 2024 |
| DRB Hygiene Services Limited | Health & social care | 2008 |