| Abbas & Lilith Ltd | Professional & scientific | 2025 |
| ABC. DEV. Force Limited | Information & communication | 2017 |
| Abelix Limited | Construction | 2016 |
| Abgexpressservices Ltd | Wholesale & retail | 2026 |
| Abhi Construction Ltd | Construction | 2019 |
| Abigol Enterprise Ltd | Health & social care | 2022 |
| Abijan Ltd | Hospitality | 2025 |
| Abisang Ltd | Wholesale & retail | 2019 |
| Abistore Ltd | Wholesale & retail | 2021 |
| Ablb Services Ltd | Construction | 2020 |
| Abloh Capital Ltd | Other services | 2025 |
| About Networks Limited | Information & communication | 2002 |
| ABR Housing Limited | Real estate | 2025 |
| Abrar Global Limited | Wholesale & retail | 2025 |
| Abrigo DOS Amigos Ltd | Hospitality | 2023 |
| Absolute Aestheticsx Academy Ltd | Education | 2020 |
| Absolute Fire Protection Limited | Construction | 2007 |
| Absolute Grace Healthcare Ltd | Health & social care | 2013 |
| Absolute Heating and Plumbing Services Limited | Administrative & support | 2009 |
| ABV Resources Limited | Professional & scientific | 2019 |
| AC Bava's Ltd | Transport & logistics | 2024 |
| AC Business Mastery Ltd | Education | 2017 |
| ACA Griff Property Limited | Real estate | 2016 |
| Academify Limited | Health & social care | 2024 |
| Academy of Sports Nutrition Ltd | Wholesale & retail | 2016 |
| Accelerated Education Limited | Extraterritorial | 2004 |
| Accelerated Education Publications Limited | Information & communication | 1999 |
| Accelerated Education Tuition Limited | Education | 2009 |
| Acceleron Ltd | Wholesale & retail | 2023 |
| Acceptance Care Limited | Hospitality | 2024 |
| Accountax Mentors Limited | Professional & scientific | 2013 |
| Accukeeper Limited | Professional & scientific | 2023 |
| Acdcuk Ltd | Professional & scientific | 2024 |
| Ace Auto Hire Ltd | Administrative & support | 2026 |
| Ace Bites Ltd | Hospitality | 2025 |
| Ace Cargo Service Ltd. | Transport & logistics | 2006 |
| Ace Facades Ltd | Construction | 2022 |
| Ace Financials Ltd | Financial services | 2025 |
| Actgreennow Ltd | Information & communication | 2022 |
| Active Property Care Ltd | Extraterritorial | 2005 |
| Aculate Consultancy Ltd | Health & social care | 2025 |
| Acuphysio Care Ltd | Health & social care | 2024 |
| AD Saini Ltd | Manufacturing | 2025 |
| Adam Home Solutions Ltd | Construction | 2026 |
| Addis Creation Ltd | Health & social care | 2025 |
| Adhira Limited | Wholesale & retail | 2016 |
| ADI Trans Express Ltd | Transport & logistics | 2016 |
| Aditi Digital Marketing Ltd | Information & communication | 2025 |
| ADL Luxury Car Ltd | Transport & logistics | 2024 |
| Administrative Entropy Index (AEI) Ltd | Information & communication | 2026 |
| Admirable Builders Ltd | Construction | 2019 |
| Admiral Accounting Ltd | Professional & scientific | 2011 |
| Admiral Strategic Consulting Ltd | Professional & scientific | 2024 |
| ADS Solutions Limited | Information & communication | 2018 |
| ADT Minibuses Ltd | Transport & logistics | 2025 |
| Advanced Brickwork Limited | Construction | 2021 |
| Advanced Systems Global Technology Ltd | Construction | 2026 |
| ADY VAL Ltd | Transport & logistics | 2025 |
| AE Online Limited | Extraterritorial | 2014 |
| Aegon Consultancy Services Limited | Information & communication | 2025 |
| AEI Bargain Ltd | Wholesale & retail | 2021 |
| Aerial Motion Ltd | Arts & recreation | 2019 |
| Aerofin IT Solutions & Consulting Services Ltd | Information & communication | 2020 |
| Aerotheon Ltd | Professional & scientific | 2023 |
| Aerotics Technologies Limited | Information & communication | 2025 |
| Aesthetics by Silvie Ltd | Health & social care | 2020 |
| Affiliate Creative Solutions Limited | Financial services | 2022 |
| AFG Global Trade Ltd | Wholesale & retail | 2026 |
| AFG Kitchen Limited | Hospitality | 2025 |
| AFG Logistic Services Ltd | Transport & logistics | 2024 |
| AFT Europe Limited | Wholesale & retail | 2014 |
| AFT Realty Ltd | Real estate | 2026 |
| AFT Shops Ltd | Wholesale & retail | 2024 |
| Aftax Limited | Professional & scientific | 2007 |
| AFZ Property Ltd | Real estate | 2025 |
| Agamdeep Transport Ltd | Transport & logistics | 2026 |
| Agbs Property Limited | Real estate | 2024 |
| AGE UK Hounslow | Health & social care | 1997 |
| AGM Entertainment Limited | Wholesale & retail | 2025 |
| Ahaan Construction Ltd | Construction | 2026 |
| Ahad Production Ltd | Professional & scientific | 2023 |
| Ahhfam Ltd | Wholesale & retail | 2025 |
| Ahmad & Co Accountants Ltd | Financial services | 2010 |
| Ahsb Ltd | Real estate | 2025 |
| Ahuja & Investment Limited | Real estate | 2020 |
| Ahuja’S Investment Ltd | Real estate | 2020 |
| AI Accountants Limited | Professional & scientific | 2025 |
| AI Technology Labs Limited | Information & communication | 2025 |
| AI Web Project Management Ltd | Professional & scientific | 2025 |
| AI4DI Ltd | Professional & scientific | 2025 |
| Aidos Property Investments Ltd | Real estate | 2016 |
| AIJ Solutions Ltd | Administrative & support | 2018 |
| Aijahan Ltd | Wholesale & retail | 2025 |
| Air FLY Transfers Ltd | Wholesale & retail | 2016 |
| Air X UK Ltd | Transport & logistics | 2023 |
| Air-Truck Forwarding Limited | | 1984 |
| Aircraft Cabin Design Ltd | Professional & scientific | 2025 |
| Airiarna Properties Ltd | Real estate | 2024 |
| Airport Cargo Care International Ltd | Transport & logistics | 2020 |
| Airport Cargo Care UK Limited | Transport & logistics | 2009 |