| Curtis Scaffolding Safe Access Ltd | Construction | 2015 |
| Custom Fit Golf Shop Ltd | Wholesale & retail | 2012 |
| Customer Service Forecasting and Planning Limited | Administrative & support | 2025 |
| Custos Construct Limited | Professional & scientific | 2026 |
| Cutbill.Co.Uk Limited | Professional & scientific | 2018 |
| CVB Technical Solutions Limited | Professional & scientific | 2012 |
| D & E Motor Accessory Supplies Ltd | Wholesale & retail | 2011 |
| D & J Investors Limited | Real estate | 2018 |
| D & M Brickwork Ltd | Construction | 2017 |
| D & S Bond Limited | Real estate | 2017 |
| D & S Shipperlee Limited | Real estate | 2018 |
| D & S Starr Holdings Limited | Real estate | 2021 |
| D & S Wright Limited | Real estate | 2016 |
| D Anderson Planning Limited | Wholesale & retail | 2008 |
| D B Hollowstone Ltd | Real estate | 2013 |
| D Crumpton Painting & Decorating Services Limited | Construction | 2001 |
| D Duggan Ltd | Professional & scientific | 2018 |
| D G Granite Factory Limited | Construction | 2011 |
| D Illingworth Utilities Limited | Energy | 2025 |
| D J C Grab Hire Limited | Construction | 2024 |
| D K Building Designs Limited | Other services | 2007 |
| D M T Plumbing & Heating Limited | Construction | 2009 |
| D Murphy Carpentry Ltd | Construction | 2019 |
| D R Tank Services Ltd | Other services | 2025 |
| D Wallis & Parents LLP | | 2025 |
| D&A Family Holdings Limited | Real estate | 2022 |
| D&H Property Solutions Ltd | Water & waste | 2026 |
| D&K Sons Limited | Construction | 2021 |
| D&L Group Mechanical & Electrical Ltd | Construction | 2025 |
| D&L Multiservices Ltd | Professional & scientific | 2025 |
| D&P Property Solutions Limited | Real estate | 2025 |
| D' Mamaki Limited | Hospitality | 2025 |
| D. Arawwawala Limited | Health & social care | 2007 |
| D.T.Tacho Calibration Ltd | Other services | 2022 |
| DA Delis Limited | Hospitality | 2026 |
| DA Healthcare Ltd | Health & social care | 2017 |
| Daarre Private Ltd | Hospitality | 2023 |
| DAB Commercial Property Ltd | Real estate | 2026 |
| DAB Security Systems Limited | Administrative & support | 2013 |
| Dacco Limited | Water & waste | 2009 |
| Daddycod Limited | Hospitality | 2026 |
| Dadisaishe Global Limited | Health & social care | 2022 |
| Daedalus Coaching Ltd | Other services | 2017 |
| Daintz Property Ltd | Real estate | 2025 |
| Dala Carpentry Ltd | Construction | 2019 |
| Dala Construction Services Ltd | Construction | 2019 |
| Dala Property Group Ltd | Real estate | 2025 |
| Daly Transport Training Limited | Education | 2021 |
| Damgabriel Ltd | Real estate | 2024 |
| DAN Cashman Ltd | Professional & scientific | 2019 |
| Danancy Holdings Limited | Financial services | 2020 |
| Danby Wood Ltd | Construction | 2024 |
| Danchris Construction Limited | | 1985 |
| Daniel Bowers Interiors Limited | Construction | 2015 |
| Danielle Phillips Property Services Limited | Real estate | 2025 |
| Danilov Construction Services Ltd | Administrative & support | 2019 |
| Daniluc Ltd | Real estate | 2019 |
| Danmech (Group) Ltd | Construction | 2022 |
| Danmech (INT) Ltd | Construction | 2022 |
| Dans Mobile Tyres Ltd | Wholesale & retail | 2024 |
| Darcie's Sandwich Fillings Ltd | Hospitality | 2013 |
| Darren Turner Golf Academy Ltd | Arts & recreation | 2014 |
| DAS Syed Consultancy Ltd | Professional & scientific | 2025 |
| Dasoliv Ltd | Professional & scientific | 2014 |
| Datavine Ltd | Professional & scientific | 2024 |
| Dauntless Yacht Centre Limited | Manufacturing | 2007 |
| Davcar (Essex) Ltd | Construction | 2015 |
| Davdale LLP | | 2023 |
| Dave JR Elmes Ltd | Construction | 2025 |
| David Duncan Mortgage Services Limited | Financial services | 2017 |
| David Morrisroe Ltd | Construction | 2022 |
| Davis Scaffolding Group Ltd | Construction | 2023 |
| Davmet Trading Co. Limited | Wholesale & retail | 1976 |
| Davmet UK Limited | Hospitality | 1992 |
| Dawson Insulation Ltd | Administrative & support | 2010 |
| DBS Pubs Limited | Hospitality | 2026 |
| DC Floor Layers Limited | Construction | 2020 |
| DCD Enterprise Holdings Limited | Financial services | 2017 |
| DCW Flooring Limited | Construction | 2015 |
| DCW Heating and Plumbing Limited | Construction | 2026 |
| DD Master Ltd | Construction | 2020 |
| DD UK Services Limited | Construction | 2025 |
| DDW Holdings Limited | Professional & scientific | 2017 |
| Dealio Limited | Information & communication | 2022 |
| Dear Diary Ltd | Information & communication | 2024 |
| Deb's Cafe & Catering Ltd | Hospitality | 2025 |
| Debco Newsagents Ltd | Wholesale & retail | 2019 |
| DEC Centre Limited | Wholesale & retail | 2026 |
| Decon Demolition & Groundworks Limited | Construction | 2015 |
| Deedee Childminding Services Ltd | Health & social care | 2026 |
| Deep Blue Trading Limited | Agriculture & fishing | 2024 |
| Defending Football Ltd | Education | 2023 |
| Degshop Limited | Wholesale & retail | 2025 |
| Dellmar Foods Limited | Wholesale & retail | 2006 |
| Delta H Consulting Ltd | Professional & scientific | 2022 |
| Deltacode Limited | Other services | 2006 |
| Deluxe Furniture Range Ltd | Wholesale & retail | 2025 |
| Demillions Limited | Health & social care | 2025 |
| Dermatetics Academy Ltd | Education | 2025 |
| Derrick Consultancy Services Limited | Information & communication | 2020 |