| ASM Subs Ltd | Wholesale & retail | 2018 |
| Asme Engineering Ltd | Construction | 1995 |
| Asme Group Ltd | Financial services | 2025 |
| Asme Property Ltd | Real estate | 2025 |
| Asna Crest Holdings Ltd | Real estate | 2025 |
| Asnc Enterprise Limited | Real estate | 2019 |
| Asovara Limited | Real estate | 2015 |
| Aspa Property Group Ltd | Hospitality | 2026 |
| Aspace Studio Ltd | Wholesale & retail | 2024 |
| Aspect Construct Ltd | Construction | 2021 |
| Aspen Growth Limited | Real estate | 2020 |
| Aspinall Cars Limited | Wholesale & retail | 2015 |
| Aspire HCM Consulting Ltd | Information & communication | 2019 |
| Aspire Homes London Limited | Construction | 2015 |
| Aspire Hospitality Management UK Limited | Hospitality | 2019 |
| Aspire House Enterprises Ltd | Health & social care | 2019 |
| Aspire House Ltd | Health & social care | 2013 |
| Aspire Learning London Ltd | Education | 2024 |
| Aspire Medical Health Limited | Health & social care | 2023 |
| Aspire Property Ventures Ltd | Real estate | 2025 |
| Aspire Softwares Limited | Information & communication | 2018 |
| ASPIRE4BETTER Ltd | Transport & logistics | 2024 |
| Aspireus Holdings Ltd | Real estate | 2022 |
| Asquare Ltd | Professional & scientific | 2011 |
| ASR Accountants Ltd | Professional & scientific | 2022 |
| ASR Estates LLP | | 2013 |
| Asra Holdings Limited | Financial services | 2017 |
| Asra Management Services LLP | | 2013 |
| ASRA80 Ltd. | Professional & scientific | 2017 |
| Assad Property Limited | Real estate | 2012 |
| Assen Ltd | Professional & scientific | 2014 |
| Asset Estate Services (UK) Limited | Real estate | 2016 |
| Asset Global Ltd | Financial services | 2024 |
| Asset Plus Ltd | Information & communication | 1995 |
| Assetbond Limited | Professional & scientific | 2005 |
| Assethive Properties Ltd | Real estate | 2025 |
| Assetrove Holding Ltd | Financial services | 2025 |
| Assetrove Ltd | Real estate | 2022 |
| Assetrove Vending Ltd | Manufacturing | 2025 |
| Assetwise Capital Limited | Real estate | 2021 |
| Associate Training Systems Ltd | Professional & scientific | 2018 |
| Association of Independent Risk & Fraud Advisors | Other services | 2013 |
| Association of Recruitment Marketing Agencies Limited | Other services | 2024 |
| Assure Financial Services Limited | Financial services | 2020 |
| Assured Business Management Ltd | Professional & scientific | 2008 |
| AST Retail Ltd | Wholesale & retail | 2025 |
| Asta Properties Limited | Real estate | 2022 |
| Astec Consultant Services (HS) Limited | Public administration | 2014 |
| Astel (UK) Limited | Wholesale & retail | 1990 |
| Astel Africa Group Ltd | Financial services | 2015 |
| Aster Business Services Limited | Professional & scientific | 2001 |
| Asterbridge Limited | Extraterritorial | 2016 |
| Asteroid Properties Ltd | Real estate | 2022 |
| Aston Aviation Services Limited | Wholesale & retail | 2020 |
| Aston Brooke Services Ltd | Other services | 2007 |
| Aston Business Park Limited | Real estate | 2019 |
| Aston Property Group Ltd | Real estate | 2018 |
| Aston Vineyard Ltd. | Agriculture & fishing | 2023 |
| Astonia Associates Limited | Professional & scientific | 2015 |
| Astons Law Limited | Professional & scientific | 2024 |
| Astra Cleaning Ltd | Administrative & support | 2026 |
| Astra Financials UK Limited | Financial services | 2012 |
| Astra LAB Studio Ltd | Information & communication | 2026 |
| Astra Prima Ltd | Information & communication | 2025 |
| Astradevs Ltd | Wholesale & retail | 2022 |
| Astral Stellar Exotech Limited | Information & communication | 2020 |
| Astrala London Limited | Wholesale & retail | 2025 |
| Astraveda Ltd | Wholesale & retail | 2023 |
| Astre Limited | Financial services | 2020 |
| Astro Arena Ltd | Education | 2025 |
| Astrofin Ltd | Information & communication | 2025 |
| Astrolabe Residential Ltd | Real estate | 2026 |
| Astron R2R Consulting Limited | Information & communication | 2021 |
| Astron Technologies Ltd | Information & communication | 2017 |
| Astrosky Limited | Wholesale & retail | 2021 |
| Astrum Aviation Limited | Professional & scientific | 2006 |
| Astrum Investment Group Ltd | Financial services | 2022 |
| Astutex Limited | Wholesale & retail | 2019 |
| ASV Computer Consultants Limited | Information & communication | 2020 |
| Asvy Properties Ltd | Real estate | 2020 |
| ASW Autoparts Ltd | Wholesale & retail | 2024 |
| Aswi & Co Ltd | Wholesale & retail | 2018 |
| AT Beauty Cosmetics Ltd | Wholesale & retail | 2024 |
| AT Centaur's Ltd | Financial services | 2020 |
| AT Centaur's Restaurants Ltd | Hospitality | 2018 |
| AT Delta Ltd | Professional & scientific | 2004 |
| AT Estates London Limited | Real estate | 2021 |
| AT Gastroenterology and Endoscopy Services Ltd | Health & social care | 2025 |
| AT the Back of Beyond Limited | Administrative & support | 2012 |
| ATA CJC Ltd | Professional & scientific | 2001 |
| ATA Decorating Ltd | Construction | 2022 |
| ATA Estates (Bigbury) LLP | | 2017 |
| ATA Estates (Brunel Holdings) LLP | | 2021 |
| ATA Estates (Brunel Manor) LLP | | 2019 |
| ATA Estates (Countrywide) LLP | | 2010 |
| ATA Estates (Hartland) LLP | | 2010 |
| ATA Estates (Longwell Green) LLP | | 2009 |
| ATA Estates (Rolle ST) LLP | | 2022 |
| ATA Estates (Rutland) LLP | | 2016 |
| ATA Estates (Spindrift) LLP | | 2014 |