| 3COL Maintenance Services Ltd | Construction | 2024 |
| 3COM (UK) Limited | Financial services | 2024 |
| 3COMMERCE Ltd | Transport & logistics | 2018 |
| 3CORE Solutions Ltd | Information & communication | 2021 |
| 3CR Limited | Professional & scientific | 2025 |
| 3CS Aquarah Ltd | Information & communication | 2019 |
| 3CS Corporate Solicitors Limited | Professional & scientific | 2012 |
| 3CS Holdings Limited | Professional & scientific | 2008 |
| 3CSB Ltd | Financial services | 2026 |
| 3CTELE.COM Limited | Information & communication | 2017 |
| 3CV Holdings Ltd | Financial services | 2022 |
| 3CV Ventures Ltd | Professional & scientific | 2023 |
| 3D - Hvac Services Limited | Construction | 2012 |
| 3D Accountants Ltd | Professional & scientific | 2026 |
| 3D Afro & European Unisex Salon Ltd | Other services | 2026 |
| 3D Art Factory Ltd | Construction | 2014 |
| 3D Audio LAB Ltd | Information & communication | 2019 |
| 3D Barber Shop Limited | Other services | 2018 |
| 3D Beauty Salon Ltd | Wholesale & retail | 2026 |
| 3D Building Home Ltd | Construction | 2019 |
| 3D Building Ltd | Construction | 2023 |
| 3D Building Survey Ltd | Construction | 2018 |
| 3D Capital & Advisory Ltd | Financial services | 2014 |
| 3D Capital Limited | Financial services | 2012 |
| 3D Certhub UK Ltd | Professional & scientific | 2025 |
| 3D Comfort Living Ltd | Real estate | 2025 |
| 3D Concept Engineering Ltd | Professional & scientific | 2025 |
| 3D Crafty Creations Ltd | Manufacturing | 2026 |
| 3D CUT Limited | Professional & scientific | 2013 |
| 3D Digital Dynamix Limited | Administrative & support | 2023 |
| 3D Dreams Ltd | Manufacturing | 2025 |
| 3D Drylining Limited | Construction | 2017 |
| 3D Dynamix Ltd | Professional & scientific | 2023 |
| 3D Elite Limited | Wholesale & retail | 2026 |
| 3D Engineering Global Limited | Professional & scientific | 2018 |
| 3D Explore Ltd | Wholesale & retail | 2022 |
| 3D EYE Limited | Arts & recreation | 2000 |
| 3D Falas (UK) Limited | Health & social care | 2024 |
| 3D FAN Lights Limited | Manufacturing | 2025 |
| 3D Filament TM Ltd | Wholesale & retail | 2024 |
| 3D Financial Ltd | Professional & scientific | 2018 |
| 3D Gens UK Ltd | Manufacturing | 2022 |
| 3D Geomatics Surveys Ltd | Professional & scientific | 2021 |
| 3D Gifts and Toys Ltd | Manufacturing | 2025 |
| 3D Global Consulting Ltd | Professional & scientific | 2018 |
| 3D Graftscan Ltd | Information & communication | 2025 |
| 3D Homes Group Limited | Financial services | 2024 |
| 3D Hong Kong Co Limited | Manufacturing | 2015 |
| 3D Hub Ltd | Professional & scientific | 2022 |
| 3D Humans Ltd | Wholesale & retail | 2023 |
| 3D Industries Limited | Information & communication | 2009 |
| 3D Infinity Ltd | Wholesale & retail | 2024 |
| 3D Info Solutions Ltd | Public administration | 2015 |
| 3D Innovations Limited | Information & communication | 2002 |
| 3D International Ltd | Real estate | 2025 |
| 3D Janitorial Services Ltd | Administrative & support | 2025 |
| 3D Kensington Ltd | Education | 2015 |
| 3D Lift Ltd | Construction | 2019 |
| 3D Lipo & Aesthetics South Ltd | Professional & scientific | 2024 |
| 3D Lipo (HQ) Ltd | Real estate | 2017 |
| 3D Lipo Brighton Ltd. | Professional & scientific | 2018 |
| 3D Lipo Holdings Ltd | Financial services | 2016 |
| 3D Lipo Investments Ltd | Financial services | 2024 |
| 3D Lipo London Ltd | Other services | 2022 |
| 3D Lipo Property Company Ltd | Real estate | 2016 |
| 3D Logic Limited | Information & communication | 2006 |
| 3D London Investments Ltd | Real estate | 2026 |
| 3D London Lamps Limited | Manufacturing | 2024 |
| 3D Makery Ltd | Wholesale & retail | 2025 |
| 3D Manufactory Ltd | Manufacturing | 2024 |
| 3D Media Ltd | Arts & recreation | 2019 |
| 3D Medtech LLP | | 2024 |
| 3D Nail & Beauty Ltd | Other services | 2022 |
| 3D Nexus Limited | Administrative & support | 2000 |
| 3D Objects LLP | | 2025 |
| 3D Parking Ltd | Administrative & support | 2010 |
| 3D People Limited | Manufacturing | 2017 |
| 3D PMS Limited | Professional & scientific | 2021 |
| 3D Print Farm Ltd | Extraterritorial | 2020 |
| 3D Printerly Ltd | Professional & scientific | 2021 |
| 3D Printers Online Store Ltd | Professional & scientific | 2019 |
| 3D Property Investment and Management Ltd | Real estate | 2025 |
| 3D Property Services (London) Limited | Construction | 2021 |
| 3D Proto-Fabricate Limited | Manufacturing | 2024 |
| 3D Savjen Limited | Construction | 2016 |
| 3D Scales Ltd | Manufacturing | 2025 |
| 3D Scan Studios Limited | Professional & scientific | 2023 |
| 3D Signs & Printers Limited | Manufacturing | 2020 |
| 3D Signs Limited | Manufacturing | 2025 |
| 3D Site Services Ltd | Construction | 2025 |
| 3D Sparrow Group Limited | Information & communication | 2016 |
| 3D Strategic Communications Ltd | Professional & scientific | 2018 |
| 3D Toolbox Limited | Information & communication | 2005 |
| 3D UX Limited | Information & communication | 2014 |
| 3D Visco Studio Limited | Professional & scientific | 2015 |
| 3D Works Ltd | Construction | 2025 |
| 3D Yachting Ltd | Extraterritorial | 2021 |
| 3D'S Building Solutions Ltd | Construction | 2020 |
| 3D-ADVENTURE Ltd | Arts & recreation | 2025 |
| 3D-LIPO Limited | Wholesale & retail | 2011 |