| Diamond Rooms Ltd | Real estate | 2024 |
| Diamond UK Property Management Ltd | Households | 2020 |
| Diamond Vale Projects Ltd | Construction | 2020 |
| Diamonds Boutique Luton Ltd | Wholesale & retail | 2015 |
| Diamonds Property Solutions Limited | Construction | 2019 |
| Diaspora Market Limited | Wholesale & retail | 2025 |
| Dibley Sporting Ltd | Arts & recreation | 2024 |
| Dibra Investments Ltd | Financial services | 2019 |
| Dicso Vapes Ltd | Wholesale & retail | 2022 |
| Didad & Co Limited | Health & social care | 2013 |
| Didi Solutions Ltd | Professional & scientific | 2026 |
| Diez Enterprise Ltd | Wholesale & retail | 2025 |
| Difcar Limited | Households | 2024 |
| Digger Services Ltd | Construction | 2019 |
| Digiforce Talent Ltd | Professional & scientific | 2017 |
| Digilearn Ltd | Education | 2020 |
| Digisouk Ltd | Wholesale & retail | 2026 |
| Digital Alloy Limited | Information & communication | 2017 |
| Digital Coder Development Limited | Information & communication | 2025 |
| Digital Crafters Limited | Information & communication | 2017 |
| Digital Design Creations Ltd | Information & communication | 2024 |
| Digital DOM Ltd | Extraterritorial | 2016 |
| Digital Hawks Limited | Professional & scientific | 2021 |
| Digital Media House Limited | Information & communication | 2017 |
| Digital Product Studio Ltd | Information & communication | 2026 |
| Digital Seniors Ltd | Professional & scientific | 2025 |
| Digital Voyage Ltd | Information & communication | 2025 |
| Digitalmandee Ltd | Information & communication | 2021 |
| Digitalrasta Ltd | Information & communication | 2024 |
| Digitech Solutions Global Limited | Information & communication | 2006 |
| Digitonomics Ltd | Real estate | 2023 |
| Digitus Accountancy Limited | Professional & scientific | 2010 |
| Digitus Lettings Ltd | Households | 2013 |
| Digitus Ltd | Professional & scientific | 2019 |
| Digitus Properties Ltd | Real estate | 2023 |
| Digs Electrical Limited | Professional & scientific | 2006 |
| Digswell Associates Limited | Professional & scientific | 1984 |
| Dija's Boutique Ltd | Wholesale & retail | 2026 |
| DIL & RAJ Constructions Ltd | Construction | 2019 |
| DIL Pazir Travels Ltd | Transport & logistics | 2019 |
| Dilai Limited | Transport & logistics | 2018 |
| Dilbagh Estates Ltd | Real estate | 2025 |
| Diligence Integration Ltd | Information & communication | 2020 |
| Dillamore Funeral Service Limited | Other services | 2013 |
| Dillis Y Tembo Limited | Health & social care | 2023 |
| Dilzy Group Ltd | Information & communication | 2019 |
| Dil’S Fashion Ltd | Wholesale & retail | 2024 |
| Dimchev Ltd | Transport & logistics | 2022 |
| Dimension Advisers Limited | Financial services | 2024 |
| Dimension Holdings Limited | Financial services | 2024 |
| Dimension Nominees Limited | Financial services | 2024 |
| Dimension Partners LLP | | 2024 |
| Dimension Professional Services Limited | Professional & scientific | 2026 |
| Dimipati Ltd | Construction | 2024 |
| Dimmock Construction Limited | Construction | 1997 |
| DIN and Co Investments Ltd | Real estate | 2025 |
| Dinash Limited | Health & social care | 2021 |
| Dinca Excavations Ltd | Construction | 2023 |
| Dincov Decoration Ltd | Construction | 2017 |
| Dine Asia Limited | Hospitality | 2003 |
| Dine MED Ltd | Information & communication | 2025 |
| Dineo Hub Ltd | Professional & scientific | 2025 |
| Dinesh International Limited | Wholesale & retail | 2020 |
| Dinkum DIM Sims UK Ltd | Wholesale & retail | 2019 |
| Diocese of ST Albans Multi-Academy Trust | Education | 2016 |
| Diocletian Ltd | Information & communication | 2025 |
| Dion Café Ltd | Hospitality | 2023 |
| Diphenol Properties Limited | Hospitality | 2025 |
| Direct Car Services Ltd | Wholesale & retail | 2019 |
| Direct Industrial Doors Limited | Wholesale & retail | 2008 |
| Direct Marketing Agency Ltd | Professional & scientific | 2024 |
| Direct Property Sales Limited | Extraterritorial | 1996 |
| Direct Trades Intercontinental Limited | Wholesale & retail | 2026 |
| DIRECT23 Transport Limited | Transport & logistics | 2023 |
| Directional Community Interest Company | Health & social care | 2013 |
| Discount Furniture Clearance Ltd | Wholesale & retail | 2014 |
| Discountmarket Ltd | Health & social care | 2025 |
| Discover Islam Luton Ltd. | Education | 2011 |
| Disets Ltd | Information & communication | 2025 |
| Dish Design Hospitality Ltd | Professional & scientific | 2024 |
| District Heating Weldtech Ltd | Construction | 2023 |
| District Property Management Ltd | Real estate | 2026 |
| Ditco Holding Ltd | Construction | 2020 |
| Diti Transport Ltd | Transport & logistics | 2025 |
| Divad Limited | Transport & logistics | 2023 |
| Diverse 16+ Ltd | Education | 2022 |
| Diverse Community Media & Training Ltd | Health & social care | 2013 |
| Diverse Computer Services Ltd | Other services | 2018 |
| Diverse CT Limited | Professional & scientific | 2015 |
| Diverse FM Community Media & Training Ltd | Education | 2006 |
| Divine Agape Care Limited | Health & social care | 2015 |
| Divine Blessings Rain Limited | Health & social care | 2023 |
| Divine Connections (London) Ltd | Administrative & support | 2010 |
| Divine Connections Wealth Management Ltd | Professional & scientific | 2025 |
| Divine Inspirations Production Limited | Information & communication | 2005 |
| Divine Natural Limited | Wholesale & retail | 2010 |
| Divine Will Estates Ltd | Real estate | 2024 |
| Divitae Property Ventures Ltd | Real estate | 2024 |
| Divvela Service Ltd | Information & communication | 2025 |
| Divyanshu Construction Ltd | Construction | 2020 |