| D H Electrics Limited | Construction | 2010 |
| D J Building Sussex Ltd | Construction | 2016 |
| D Knight Agricultural Contractors Limited | Administrative & support | 2013 |
| D L Field Estates Limited | Construction | 2018 |
| D Malde Ltd | Health & social care | 2015 |
| D Seladjins Limited | Financial services | 2013 |
| D&A Car Wash Ltd | Administrative & support | 2025 |
| D&H Surrey Limited | Health & social care | 2021 |
| D&H Surrey Medical Limited | Health & social care | 2025 |
| D&H Surrey Property Ltd | Real estate | 2023 |
| D&M Mistry Limited | Health & social care | 2021 |
| D&P Handyman Ltd | Construction | 2023 |
| D.G. Palmer Limited | Construction | 1999 |
| D2 Dental Ltd | Health & social care | 2019 |
| DA Dental Limited | Health & social care | 2025 |
| DA LUX Glow Aesthectic Solutions Ltd | Health & social care | 2025 |
| DA Vinci Hotel Limited | Hospitality | 2023 |
| DAB Southern Limited | Construction | 2013 |
| Dabyos Healthcare Ltd | Health & social care | 2016 |
| Dacom Sure Limited | Financial services | 2022 |
| Dahms Brothers Ltd | Wholesale & retail | 2024 |
| Daikon Services Ltd | Real estate | 2023 |
| Daily Bread Consultancy Ltd | Professional & scientific | 2021 |
| Daisy Finance (UK) Ltd | Financial services | 2014 |
| Daisy Windows Limited | Construction | 2000 |
| Dakatra Holdings Ltd | Financial services | 2026 |
| Dakatra Ltd | Health & social care | 2019 |
| Dakota Biome Limited | Wholesale & retail | 2026 |
| Dakota Skincare Limited | Wholesale & retail | 2026 |
| Dalal & Co UK Limited | Health & social care | 2003 |
| Daldy Holding Ltd | Financial services | 2023 |
| Dalibhunga Limited | Health & social care | 2019 |
| Daltons Ltd | Professional & scientific | 2022 |
| DAN Medica South Limited | Manufacturing | 2002 |
| Danahar Property Limited | Real estate | 2010 |
| Daneco Medical Secretarial Services Ltd | Professional & scientific | 2016 |
| Daniel Hawkes Limited | Health & social care | 2022 |
| Daniel Jenkins Law Limited | Administrative & support | 2019 |
| Daniel KGT Ltd | Transport & logistics | 2015 |
| Danielle Taylor Dentistry Ltd | Health & social care | 2024 |
| Dann Electrical Services Ltd | Construction | 2020 |
| Dann Property Developments Limited | Real estate | 2025 |
| Danrell Limited | Health & social care | 2022 |
| Dans News & Supermarket Limited | Wholesale & retail | 2017 |
| Dany 77 Ltd | Construction | 2018 |
| Daphne Ltd | Professional & scientific | 2026 |
| Darfoor Heights Ltd | Health & social care | 2012 |
| Dark Amor Tattooing Ltd | Other services | 2025 |
| Dark Amor Vanity Clinic Ltd | Other services | 2019 |
| Dark Hologram Ltd | Professional & scientific | 2014 |
| Dark Smoke Limited | Hospitality | 2023 |
| Darkflight Limited | Administrative & support | 2025 |
| Darren James Consulting Ltd | Professional & scientific | 2022 |
| Darren Tingey Limited | Construction | 2005 |
| Dartford Beauty Studio Limited | Other services | 2015 |
| Dastben Trading Ltd | Other services | 2026 |
| Datafortified Limited | Information & communication | 2024 |
| Davcad Ltd | Professional & scientific | 2009 |
| Dave Brinson and Associates Ltd | Administrative & support | 2018 |
| Dave Sands Tree Surgeon Limited | Other services | 2014 |
| Davenport Safety Services Ltd | Professional & scientific | 2014 |
| David Christopher Estate Agents Limited | Real estate | 2002 |
| David Christopher Financial Management Ltd | Financial services | 2002 |
| David Crouch Electrical Services Limited | Construction | 2008 |
| David Douglas (Farms) Limited | Agriculture & fishing | 1976 |
| David F Johnson Limited | Professional & scientific | 2022 |
| David Gunn Safety Services Ltd | Professional & scientific | 2015 |
| David Kerr Consulting Ltd | Professional & scientific | 2018 |
| David Powell Distribution Limited | Extraterritorial | 1991 |
| David Rumm Limited | Professional & scientific | 2011 |
| David Salmon Furnishers Limited | Wholesale & retail | 2013 |
| David&Sons Healthcare Ltd | Health & social care | 2015 |
| Davidscakes Ltd | Wholesale & retail | 2025 |
| Davies Williams Surgical Services Limited | Health & social care | 2013 |
| Davpin Limited | Health & social care | 2020 |
| Dawber Brothers Limited | Construction | 2004 |
| Dawber Developments Ltd | Real estate | 2025 |
| Dawber Holdings Ltd | Real estate | 2023 |
| Dawmouse Furniture Ltd | Wholesale & retail | 2021 |
| Daysofmay Ltd | Wholesale & retail | 2020 |
| DB Builders Media Ltd | Information & communication | 2025 |
| DB Builders Sussex Limited | Construction | 2014 |
| DB Transport Group Ltd | Transport & logistics | 2025 |
| Dbcsml Limited | Real estate | 2019 |
| DBM Decorating Ltd | Construction | 2026 |
| DC Electrical Traction Services Limited | Transport & logistics | 2015 |
| DC Heating Plumbing & Renewables Ltd | Construction | 2025 |
| DCS LEE Ltd | Health & social care | 2021 |
| Dct-Performance Ltd | Wholesale & retail | 2015 |
| DE LA Cuisine Ltd | Hospitality | 2021 |
| DE Marco Male Grooming Ltd | Other services | 2024 |
| DE Parys Dental Ltd | Health & social care | 2022 |
| DE Roos Court Management Company Limited | Households | 1972 |
| DE Walden Court (Eastbourne) Limited | Households | 2005 |
| DE Walden Estates Limited | Real estate | 2021 |
| DE Walden Mews Management Company Limited | Households | 1999 |
| Dead Hung Productions Ltd | Arts & recreation | 2023 |
| Deallow Limited | Construction | 1979 |
| Dean Christmas Limited | Professional & scientific | 2019 |
| Deanland Flight Training Ltd | Arts & recreation | 2017 |