| Cultural Heritage Digitisation Limited | Professional & scientific | 2013 |
| Cumbia Speciality Coffee Ltd | Hospitality | 2021 |
| Cumbrae Group Limited | Administrative & support | 2016 |
| Cumbrae Promotions Limited | Arts & recreation | 2016 |
| Cunningham Associates Limited | Professional & scientific | 1998 |
| Cura Cars Ltd | Information & communication | 2026 |
| Curley Capital Associates Limited | Professional & scientific | 2019 |
| Curley Real Estate Limited | Real estate | 2017 |
| Curzon Management & Investments Limited | Professional & scientific | 2009 |
| Custom 1 Ltd | Other services | 2019 |
| CUT the Carbon Limited | Professional & scientific | 2024 |
| Cutmaster Barber Shop Ltd | Other services | 2023 |
| CV Lighting Ltd | Wholesale & retail | 2024 |
| CW Measure Ltd | Construction | 2023 |
| Cyhesion Ltd | Information & communication | 2017 |
| CYN Agency Ltd | Professional & scientific | 2024 |
| D S Walsh Limited | Construction | 2011 |
| D T C Roofing Services Ltd | Construction | 2023 |
| D&D Properties Holdings Ltd | Financial services | 2025 |
| D.Finitive Ltd | Manufacturing | 2025 |
| D.N.A. Limited | Information & communication | 1982 |
| D.T.M.I.C. Limited | Information & communication | 1997 |
| DA Associates Ltd | Professional & scientific | 2024 |
| Daily Tradingfinancegroup Ltd | Financial services | 2025 |
| Daje Consultancy Ltd | Administrative & support | 2024 |
| Dale Accounting and Tax Services Ltd | Professional & scientific | 2012 |
| Daleday Property Management Limited | Households | 2003 |
| Damiano Petrucci Productions Ltd | Information & communication | 2019 |
| Danakol Ltd | Information & communication | 2023 |
| Daniel Enterprises Ltd | Administrative & support | 2023 |
| Daniela Golea Ltd | Transport & logistics | 2025 |
| Dannybdesign Ltd | Manufacturing | 2015 |
| DAP Consultancy Services Ltd | Professional & scientific | 2025 |
| Dariya Ltd | Health & social care | 2026 |
| Dark Jumper Limited | Wholesale & retail | 2022 |
| Dark Signal Ltd | Information & communication | 2014 |
| Dark Star Labs Ltd | Information & communication | 2023 |
| Darren Cavozzi Ltd | Construction | 2013 |
| Daska Services Ltd | Real estate | 2026 |
| Databolt Ltd | Information & communication | 2024 |
| Dataclear AI Ltd | Information & communication | 2025 |
| Datanaed Consulting Ltd | Information & communication | 2021 |
| Datolabs Limited | Information & communication | 2017 |
| Daulat Limited | Health & social care | 2015 |
| Daulaut Great UK Ltd | Wholesale & retail | 2025 |
| David Maxwell Assets Ltd | Real estate | 2009 |
| David Patterson Ltd | Wholesale & retail | 2025 |
| David Taylor Creative Solutions Ltd | Administrative & support | 2019 |
| Davies Creative Property Ltd | Construction | 2021 |
| Davis Entertainment Limited | Wholesale & retail | 2025 |
| Dawes Road Properties Limited | Real estate | 2023 |
| Dawkins Analytics Limited | Health & social care | 2025 |
| DAY04 Limited | Administrative & support | 2024 |
| DB (Epsom) Properties Limited | Real estate | 2025 |
| DB Document Solutions Limited | Information & communication | 2017 |
| DB Skin Ltd | Other services | 2023 |
| Dbio Limited | Arts & recreation | 2017 |
| DC Advisory and Consulting Ltd | Information & communication | 2024 |
| DC Management Limited | Information & communication | 2016 |
| DD Business Solutions Ltd | Professional & scientific | 2006 |
| DDH Homes Ltd | Real estate | 2020 |
| DDK Contractors Ltd | Construction | 2023 |
| DDK Empire Ltd | Real estate | 2023 |
| Ddms Consulting Ltd | Information & communication | 2006 |
| Dead Ready Productions Limited | Information & communication | 2011 |
| Deals Hunters Ltd | Wholesale & retail | 2022 |
| Dearyband Ltd | Information & communication | 2024 |
| Debstone Ltd | Wholesale & retail | 2026 |
| Decargroup (Transport Planning) Ltd | Professional & scientific | 2025 |
| Decibelle Limited | Professional & scientific | 2014 |
| Decor & Craft United Limited | Wholesale & retail | 2015 |
| Decorate With Emily Limited | Other services | 2026 |
| Decox Limited | Construction | 2025 |
| Dedo Limited | Health & social care | 2020 |
| Deebridge Developments Limited | Real estate | 1960 |
| Deedee Property Services Ltd | Construction | 2023 |
| Deep Strategy Ltd | Professional & scientific | 2014 |
| Deepjyoti Educational Services Ltd | Education | 2025 |
| Deere & Moseley Limited | Professional & scientific | 2007 |
| Degs Music Ltd | Information & communication | 2024 |
| Delaney Grey Management LP | | 2018 |
| Delicious Deli Ltd | Hospitality | 2019 |
| Delicious Ideas Ltd | Transport & logistics | 2013 |
| Delirious Blacksmith Management Limited | Information & communication | 1999 |
| Delta Catering Ltd | Hospitality | 2024 |
| Delta Wisdom Ltd | Professional & scientific | 2009 |
| Delteq Ltd | Construction | 2018 |
| Demeter Corporation Limited | Professional & scientific | 2006 |
| Denar Holdings Limited | Financial services | 2025 |
| Denar Property Services Ltd | Real estate | 2018 |
| Denar Secretarial Services Ltd | Administrative & support | 2023 |
| Dentaluxe Limited | Health & social care | 2017 |
| Denton Court Residents Association Limited | Households | 1978 |
| Depika Ltd | Arts & recreation | 2021 |
| Desi Flavour One Limited | Hospitality | 2016 |
| Designlens Ltd | Information & communication | 2022 |
| Designlife Associates Limited | Professional & scientific | 2015 |
| Dessert Line London Ltd | Hospitality | 2025 |
| DEV Systems Limited | Information & communication | 2015 |
| Devon Quantitative Services Limited | Financial services | 2009 |