| 10TH Planet Milton Keynes Ltd | Arts & recreation | 2025 |
| 12346693 Limited | Extraterritorial | 2019 |
| 14 Bond Street Limited | Financial services | 2024 |
| 19SIXTYFIVE Limited | Financial services | 2023 |
| 1VN Ltd | Financial services | 2024 |
| 2 Four Design Services Ltd | Professional & scientific | 2024 |
| 202C Limited | Professional & scientific | 2021 |
| 275 Sydenham Road Ltd | Extraterritorial | 2010 |
| 2929 Ltd | Information & communication | 2007 |
| 2NX Film Ltd | Information & communication | 2024 |
| 3 Point Consulting Limited | Information & communication | 2024 |
| 3D Design Associates Ltd | Extraterritorial | 2012 |
| 3D Wealth Partners Limited | Financial services | 2010 |
| 47 Chichele Road Freehold Limited | Real estate | 2013 |
| 53-55A Brackley Road Management Company Limited | Administrative & support | 2019 |
| 56 Canning Road London N5 2JS Limited | Households | 2010 |
| 56 Kenilworth Road Freehold Limited | Households | 2024 |
| 82.5 Ltd | Information & communication | 2023 |
| 878 Recordings Limited | Information & communication | 2018 |
| 8BALL Marketing Ltd | Professional & scientific | 2022 |
| 91 to 97 Broad Street Devco Limited | Real estate | 2020 |
| A B Race Engineering Limited | Wholesale & retail | 2023 |
| A Byrne Consultancy Limited | Administrative & support | 2017 |
| A Hickford Homes Limited | Real estate | 2019 |
| A Hickford Lighting Limited | Construction | 2017 |
| A J Hardscaping Services Limited | Construction | 2025 |
| A J Walker Limited | Construction | 2014 |
| A W Stratton Ltd | Administrative & support | 2004 |
| A Yung Limited | Professional & scientific | 2025 |
| A&C Redmond Hydraulic Services Limited | Professional & scientific | 2026 |
| A&R Legacy Ltd | Administrative & support | 2024 |
| A. J. Fraser Engineering Ltd | Professional & scientific | 2014 |
| A.C.A. Howe International Limited | Mining & quarrying | 2015 |
| A2D Social Limited | Professional & scientific | 2024 |
| Aaacleaning Ltd | Administrative & support | 2025 |
| Abbey END Leisure Ltd | Hospitality | 2020 |
| Abc.Xyz Holdings Ltd | Information & communication | 2016 |
| Able Plumbing Services Ltd | Construction | 2019 |
| Ablerise Ltd | Professional & scientific | 2025 |
| Ablinq Limited | Other services | 2014 |
| Abode Creations Ltd | Construction | 2019 |
| Above and Below PAR Limited | Administrative & support | 2023 |
| Abthorpe Broadband Association Limited | Other services | 2003 |
| AC Gibson Consulting Ltd | Professional & scientific | 2025 |
| Access (UK) Education Ltd. | Education | 2012 |
| Access Security Solutions (Group) Ltd | Administrative & support | 2013 |
| Ace Solutions Limited | Professional & scientific | 2009 |
| Ace Tracking Ltd | Wholesale & retail | 2023 |
| Achim Cremer Consult Limited | Professional & scientific | 2016 |
| Acres Land and Planning Services Ltd | Professional & scientific | 2015 |
| Actifhr Limited | Professional & scientific | 2014 |
| Action Volunteers Limited | Extraterritorial | 2017 |
| AD Landscapes and Maintenance Limited | Administrative & support | 2017 |
| Adams Avenue Rentals Ltd | Real estate | 2017 |
| Adaptive Security Limited | Administrative & support | 2015 |
| ADB Holdco Ltd | Financial services | 2024 |
| Addacard Limited | Administrative & support | 2007 |
| Aden Motors Ltd | Wholesale & retail | 2025 |
| Adhd & ASD Assessments Ltd | Health & social care | 2025 |
| Adlington HR Solutions Limited | Administrative & support | 2014 |
| Admiral EGG Games Ltd | Information & communication | 2024 |
| Adnitt Properties Ltd | Real estate | 2021 |
| Adolosi Ltd | Professional & scientific | 2009 |
| Advanced Loft Ladders Ltd | Construction | 2013 |
| Adventure 4 YOU Ltd | Education | 2024 |
| Aera Essence Ltd. | Wholesale & retail | 2024 |
| Aerial Drone Services Ltd | Professional & scientific | 2019 |
| Aeron Aviation Ltd | Transport & logistics | 2026 |
| Aesthetics by Tracy Ltd | Other services | 2021 |
| Aeternitas Ltd | Wholesale & retail | 2020 |
| AG Additive Manufacturing Ltd | Professional & scientific | 2020 |
| Agadi Property Lettings Ltd | Real estate | 2019 |
| Agricair World Wide Ltd | Water & waste | 2016 |
| Agricon Safety Ltd | Education | 2024 |
| AHI Building Services Ltd | Construction | 2024 |
| AHI Kitchens and Bathrooms Ltd | Construction | 2024 |
| AHI Landscaping Ltd | Administrative & support | 2023 |
| AHI Maintenance and Decorating Ltd | Construction | 2023 |
| AI Agencies Ltd | Professional & scientific | 2025 |
| Aidkee Limited | Information & communication | 2017 |
| Aile Investments Ltd | Real estate | 2025 |
| AIM Logic LLP | | 2013 |
| Ainger Consultancy Ltd | Other services | 2023 |
| Air CON Services (UK) Limited | Construction | 2011 |
| Air to Air Centre Ltd | Wholesale & retail | 2022 |
| Airlie Unsworth Holdings Ltd | Financial services | 2022 |
| AIW Business Solutions Limited | Professional & scientific | 2023 |
| AJ Design & Build Ltd | Construction | 2009 |
| AJN Consulting Ltd | Professional & scientific | 2023 |
| AJP Bathrooms & Boilers Limited | Construction | 2025 |
| Ajpb Ltd | Real estate | 2006 |
| AJS Estates Ltd | Real estate | 1998 |
| Alan Gray Marketing Services Ltd | Other services | 2019 |
| Alban Mann LLP | | 2017 |
| Albery Limited | Real estate | 2024 |
| Albion Consulting Ltd | Professional & scientific | 2026 |
| Alex Halsey Limited | Professional & scientific | 2018 |
| Alexuspristine Ltd | Professional & scientific | 2023 |
| Alford Court Company (Sutton-On-Sea) (1995) Limited | Real estate | 1995 |
| Alientech UK Ltd | Wholesale & retail | 2020 |