| Abstract Focus Labs Ltd. | Wholesale & retail | 2024 |
| Academe Limited | Education | 2016 |
| Academy for Business Leaders and Entrepreneurs Ltd | Professional & scientific | 2009 |
| Accounting and Linguistic Consultancy Services Ltd | Professional & scientific | 2014 |
| Ace PM Limited | Professional & scientific | 2018 |
| ACG Pathology Ltd | Health & social care | 2020 |
| Achilles Logistics Ltd | Transport & logistics | 2025 |
| Acker-Tech Limited | Information & communication | 2025 |
| Ackerman Pierce Capital Group Ltd | Financial services | 2026 |
| Ackerman Pierce Education Ltd | Education | 2024 |
| Ackerman Pierce Group Ltd | Administrative & support | 2024 |
| Ackerman Pierce Holdings Limited | Financial services | 2025 |
| Ackerman Pierce Limited | Administrative & support | 2013 |
| Acqua Kitchens Ltd | Wholesale & retail | 2007 |
| Acre 1144 Limited | Administrative & support | 2011 |
| Acrux Resources (UK) Limited | Financial services | 2023 |
| ACS Digital Limited | Information & communication | 2025 |
| ACS Time Critical Services Group Limited | Financial services | 2024 |
| Action Reign Company (A.R.C.) Limited | Hospitality | 1997 |
| Actionline Research and Training Limited | Professional & scientific | 2002 |
| Adam Stapley Plumbing Ltd | Other services | 2019 |
| Adam Wedd Ltd | Information & communication | 2021 |
| Adashe Fire Ltd | Public administration | 2025 |
| Adashe IS Ltd | Information & communication | 2025 |
| Adchaya Ltd | Wholesale & retail | 2026 |
| ADD That Little Extra Group Limited | Extraterritorial | 2016 |
| ADD That Little Extra International Limited | Extraterritorial | 2016 |
| ADD That Little Extra Limited | Information & communication | 2023 |
| Addup.Money Ltd | Information & communication | 2019 |
| Adelaide Flats Ltd | Households | 2020 |
| Adelina 92 Ltd | Administrative & support | 2019 |
| Adelina Infra Limited | Professional & scientific | 2025 |
| ADF & N Limited | Hospitality | 2021 |
| ADF Electrical Ltd | Construction | 2021 |
| ADF Property Services Ltd | Construction | 2021 |
| ADG2.0 Ltd | Real estate | 2025 |
| ADI Petrov Ltd | Transport & logistics | 2019 |
| Admore People Limited | Administrative & support | 2023 |
| Adolphus Recruitment Consultancy Service Ltd | Health & social care | 2015 |
| Adroit Interim Management Ltd | Professional & scientific | 2015 |
| Adventure Conservation Limited | Administrative & support | 2023 |
| Adventure Transport Limited | Transport & logistics | 2006 |
| Advice France Limited | Professional & scientific | 2006 |
| AE Convenience Ltd | Wholesale & retail | 2022 |
| Aecco Engineering Consultancy Limited | Professional & scientific | 2016 |
| Aeonian River Properties Ltd | Real estate | 2022 |
| Aesme Ltd | Wholesale & retail | 2016 |
| Aessis Technology Ltd | Information & communication | 2021 |
| Aesthetic With Dignity Ltd | Health & social care | 2026 |
| Aesthetics BTX Ltd | Other services | 2023 |
| Aether Hair and Spa Limited | Other services | 2016 |
| Affinity Estates (Consulting) Limited | Construction | 2021 |
| Affinity Estates Limited | Real estate | 2010 |
| Affinity United Group Ltd | Other services | 2025 |
| Affordable Spaces Group Ltd | Real estate | 2018 |
| Afghan Voice CIC | Information & communication | 2012 |
| Africa New Energies Limited | Information & communication | 2012 |
| Africanborn Investments Ltd | Real estate | 2020 |
| Afrocaine Ltd | Information & communication | 2011 |
| Afropride Ltd | Health & social care | 2019 |
| AG Exchange Ltd | Wholesale & retail | 2024 |
| AG Medical Ltd | Health & social care | 2021 |
| Agape Management Consultancy Limited | Professional & scientific | 2011 |
| Agnel and Ayona Ltd | Health & social care | 2021 |
| Agon Demeter Ltd | Professional & scientific | 2015 |
| Agora Rock Ltd | Other services | 2025 |
| Agra KT6 Ltd | Hospitality | 2025 |
| Agra Restaurant (Surbiton) Ltd | Hospitality | 2015 |
| Agroimport UK Ltd | Wholesale & retail | 2025 |
| AH Atelier Ltd | Other services | 2026 |
| AH Framing and Art Ltd | Wholesale & retail | 2021 |
| Ahmadi Sales Ltd | Information & communication | 2026 |
| Ai-Telier Ltd | Professional & scientific | 2025 |
| Aiden Global Trading Ltd | Administrative & support | 2021 |
| AIM Industry Management Ltd | Construction | 2022 |
| Air Charter Service Group Limited | Financial services | 2000 |
| Air Charter Service Leasing Limited | Transport & logistics | 2024 |
| Air Charter Service Limited | Transport & logistics | 1990 |
| Air Charter Service Trustee Company Ltd. | Professional & scientific | 2007 |
| Air Courier Service Ltd | Transport & logistics | 2009 |
| Airecast Limited | Information & communication | 2023 |
| Airlift Acquisition Bidco Limited | Professional & scientific | 2022 |
| Airlift Midco 2 Limited | Professional & scientific | 2022 |
| Airlift Midco Limited | Professional & scientific | 2022 |
| Airport Transport Network Ltd | Administrative & support | 2017 |
| Airr Plus Limited | Other services | 2024 |
| Airside Andy Holdings Limited | Other services | 2013 |
| Airside Andy Limited | Other services | 2009 |
| Aisha & Kaveet Holding Ltd | Financial services | 2025 |
| Aisha & Kaveet Ltd | Real estate | 2024 |
| AJ Driving School Ltd | Education | 2014 |
| AJP FD Services Ltd | Professional & scientific | 2023 |
| AK Barbers House Ltd | Other services | 2024 |
| AK Whymark Architects Ltd | Professional & scientific | 2021 |
| AKA Europe Limited | Professional & scientific | 2023 |
| Akgis Ltd | Financial services | 2023 |
| Aksel Digital Ltd | Wholesale & retail | 2016 |
| AKZ Consultants Ltd | Professional & scientific | 2024 |
| AL Capone Barber Ltd | Other services | 2019 |
| AL05 Building Limited | Construction | 2025 |