| AS Built Data Limited | Administrative & support | 2016 |
| AS Good AS Grass (UK) Ltd | Administrative & support | 2014 |
| AS Property Holdings Ltd | Real estate | 2022 |
| Asbestos Assessment and Control Limited | Professional & scientific | 2002 |
| Asbestos Garage Roofs Limited | Construction | 2022 |
| ASC 4 FS Limited | Professional & scientific | 2012 |
| Ascend Consultancy Limited | Professional & scientific | 2022 |
| Ascot Circle Ltd | Wholesale & retail | 2020 |
| Asdullah Limited | Manufacturing | 2023 |
| ASF Designs Ltd | Professional & scientific | 2025 |
| Ashbourne Care Home Ltd | Administrative & support | 2002 |
| Ashfield Property Management Ltd | Wholesale & retail | 2025 |
| Ashfold Properties Limited | Real estate | 2023 |
| Ashfold Quality Meats Limited | Wholesale & retail | 2008 |
| Ashford Lloyd Ltd | Administrative & support | 2026 |
| Ashley M Gowers Holdings Limited | Real estate | 2024 |
| Ashton Photographics Limited | Manufacturing | 2001 |
| Ashton's (Bury) Limited | Professional & scientific | 2024 |
| Ashverica Solutions Ltd | Professional & scientific | 2015 |
| Ashvika Ltd | Hospitality | 2024 |
| Ashwood Vale (Buxton) Management Company Limited | Households | 2006 |
| Ashworth Court (Radcliffe) Limited | Households | 1994 |
| Ashworth Home Services Ltd | Administrative & support | 2008 |
| Asian Delicacies Limited | Hospitality | 2025 |
| ASP Bar Consultancy Ltd | Hospitality | 2018 |
| Aspect Accounting Limited | Professional & scientific | 2001 |
| Aspect Recruitment Ltd | Administrative & support | 2014 |
| Aspect Taxation Services Ltd | Professional & scientific | 2017 |
| Aspecto Holdings Limited | Wholesale & retail | 2015 |
| Aspin Cleaning Ltd | Administrative & support | 2024 |
| Aspin Facilities Ltd | Administrative & support | 2024 |
| Aspin Group Limited | Real estate | 2024 |
| Aspin Property Holdings Ltd | Real estate | 2025 |
| Aspin Property Ltd | Households | 2024 |
| Aspire Accountancy Ltd | Professional & scientific | 2016 |
| Aspire Data Recruitment Limited | Administrative & support | 2000 |
| Aspire Greenmount Ltd | Other services | 2013 |
| Aspire Learning Centres & Childcare Limited | Education | 2015 |
| Aspire Motors Ltd | Wholesale & retail | 2026 |
| Aspire Software Holdings Ltd | Information & communication | 2022 |
| Aspire Software Systems Holdings Limited | Financial services | 2020 |
| Aspire Software Systems Limited | Information & communication | 2019 |
| ASR Business Development Ltd | Professional & scientific | 2014 |
| Asset Management and Compliance Ltd | Professional & scientific | 2025 |
| Asset Protect Group Ltd | Wholesale & retail | 2026 |
| Assh Properties Ltd | Real estate | 2023 |
| Associate Health Ltd | Health & social care | 2021 |
| Assured Laundry Services Ltd | Other services | 2025 |
| Assured Stays Management Limited | Hospitality | 2023 |
| AST Hampsons LLP | | 2015 |
| Astin & Law Accountants Ltd | Professional & scientific | 2025 |
| Aston Knight Solicitors Limited | Professional & scientific | 2011 |
| Astra Distribution (MCR) Limited | Wholesale & retail | 2003 |
| Astro Pro Ltd | Other services | 2021 |
| Astute Consultancy Ltd | Information & communication | 2025 |
| ASY Accountants Ltd | Professional & scientific | 2018 |
| AT Hair & Beauty Ltd | Other services | 2009 |
| Atari Chiro Ltd | Health & social care | 2025 |
| ATB Industries (Northwest) Ltd | Other services | 2016 |
| ATC Legal Limited | Information & communication | 2025 |
| Atherward Limited | Real estate | 1999 |
| Athleisure Limited | Professional & scientific | 1991 |
| Athlete Apparel Limited | Wholesale & retail | 2024 |
| Athol Paints Bury Limited | Manufacturing | 2026 |
| Athol Paints Limited | Manufacturing | 1976 |
| Atkins Beds and Furniture Limited | Wholesale & retail | 2016 |
| ATL Properties Ltd | Real estate | 2025 |
| Atlantic Fish and Chips Bar Ltd | Hospitality | 2022 |
| Atlantic Outlet Limited | Wholesale & retail | 2018 |
| Atlantic Superyacht Services Ltd | Manufacturing | 2018 |
| Atlantis Astute Ltd | Information & communication | 2025 |
| Atlantis Capital Invest Ltd | Manufacturing | 2014 |
| Atlantis Diamond Concepts Ltd | Information & communication | 2025 |
| Atlantis Import and Export Ltd | Information & communication | 2025 |
| Atlantis Traders UK Ltd | Wholesale & retail | 2019 |
| Atlas & Co Accountants Ltd | Professional & scientific | 2023 |
| Atom Business Performance Limited | Professional & scientific | 2022 |
| Atomic Tuition Ltd | Education | 2021 |
| Atria Accountants Ltd | Professional & scientific | 2020 |
| Atria Group Holdings Ltd | Professional & scientific | 2025 |
| Atrium Capital Group Ltd | Real estate | 2023 |
| Attollo Intranet Ltd | Administrative & support | 2022 |
| Atwa Limited | Real estate | 2023 |
| AU Pharmacare Ltd | Public administration | 2023 |
| Aucano Technologies Limited | Information & communication | 2017 |
| Auction Agent Ltd | Real estate | 2019 |
| Auction Finance Limited | Extraterritorial | 2014 |
| Audi Tech Ltd | Wholesale & retail | 2026 |
| Audio Maintenance Limited | Manufacturing | 2002 |
| Auditrisknet Ltd | Professional & scientific | 2010 |
| August Blake Developments Limited | Real estate | 1998 |
| August Blake Public Limited Company | Professional & scientific | 2001 |
| Aukg Ltd | Wholesale & retail | 2026 |
| AUL Developments Limited | Construction | 2017 |
| AUM Direct Limited | Extraterritorial | 2003 |
| Auma Optical Ltd | Health & social care | 2022 |
| Aunty Ji's Ltd | Hospitality | 2019 |
| Aura Elite Cleaning Ltd | Administrative & support | 2025 |
| Aurum Signo Ltd | Other services | 2025 |
| Authentic Noodle Company Limited | Administrative & support | 1998 |