| Asya Cafe Ltd | Hospitality | 2026 |
| AT Olus Ltd | Information & communication | 2025 |
| AT Video Ltd | Information & communication | 2025 |
| At&T Contractors Limited | Administrative & support | 2015 |
| At-Spot MIX Limited | Manufacturing | 2016 |
| ATD Design Solutions Ltd | Construction | 2017 |
| Ateri Medicare Ltd | Health & social care | 2022 |
| ATF Fitness Ltd | Arts & recreation | 2019 |
| Athena Circus Academy Ltd | Other services | 2022 |
| Athena Fitness Ltd | Arts & recreation | 2003 |
| Athwal Enterprise Limited | Real estate | 2025 |
| Atigrac Limited | Health & social care | 2023 |
| Atkinson-Cross Ltd | Construction | 2021 |
| Atlas Combustion Engineering Limited | Manufacturing | 1994 |
| Atlas Global Textiles Ltd | Wholesale & retail | 2023 |
| Atlas Pathways Ltd | Transport & logistics | 2026 |
| Atlh Limited | Administrative & support | 2025 |
| ATN Partnership (Holdings) Ltd | Real estate | 2018 |
| ATN Partnership Limited | Professional & scientific | 2010 |
| ATN Probate Ltd | Professional & scientific | 2022 |
| Atom FM Group Ltd | Professional & scientific | 2025 |
| Atoo Ltd | Information & communication | 2019 |
| ATS Wireless Ltd | Professional & scientific | 2022 |
| ATV Industrial Plumbing Supplies Ltd. | Wholesale & retail | 2001 |
| Atwal Investments Limited | Hospitality | 2009 |
| Atwal Ditton Investments 2 Limited | Hospitality | 2024 |
| Atwal Ditton Investments Limited | Hospitality | 2019 |
| Atwal Maidstone Investments Limited | Hospitality | 2017 |
| Atwal Management Group Limited | Professional & scientific | 2018 |
| Atwal Northern Investments Limited | Hospitality | 2013 |
| Atwal Rainham Investments Limited | Hospitality | 2014 |
| Audez Drainage Services Limited | Administrative & support | 2011 |
| Augmosco Ltd | Administrative & support | 2017 |
| Aujla Crosshands Ltd | Arts & recreation | 2020 |
| Aulakh Transport Services Limited | Transport & logistics | 2025 |
| AUM Fashions Limited | Wholesale & retail | 2017 |
| Auntiego Ltd | Wholesale & retail | 2025 |
| Aura 14 Limited | Hospitality | 2026 |
| Auraspace Group Ltd | Hospitality | 2026 |
| Auris Builders Ltd | Construction | 2016 |
| Auror Ltd | Wholesale & retail | 2016 |
| Aurora Health and Fitness Ltd | Health & social care | 2008 |
| Aurora Logistics Ltd | Transport & logistics | 2025 |
| Aurora Spa Health and Beauty Limited | Wholesale & retail | 2015 |
| Aurora’S Cafe Limited | Hospitality | 2020 |
| AUS Rise Ltd | Information & communication | 2024 |
| Autism South East C.I.C. | Other services | 2019 |
| Autisme Solutions Ltd | Public administration | 2023 |
| Auto Accident Assistance Ltd | Other services | 2023 |
| Autocruse Service Centre Limited | Wholesale & retail | 2014 |
| Autofix (Ebbsfleet) Limited | Wholesale & retail | 2008 |
| Automatix Limited | Administrative & support | 2015 |
| Autos Delux Limited | Wholesale & retail | 2018 |
| Autosafety Centres (U.K.) Limited | Extraterritorial | 1980 |
| Autovu Solutions Ltd | Administrative & support | 2014 |
| AV City Minimart Ltd | Wholesale & retail | 2019 |
| Avalon Builders (London) Ltd | Construction | 2017 |
| Avangarde Analytics Ltd | Information & communication | 2018 |
| Avanka Dixit Prime Realty Ltd | Real estate | 2025 |
| Avarlo Ltd | Professional & scientific | 2025 |
| Avenor Software Limited | Information & communication | 2026 |
| Aventic Limited | Information & communication | 2026 |
| AVI JAT Transport Ltd | Transport & logistics | 2026 |
| Avior One Limited | Real estate | 2026 |
| Avitaghana Ltd | Administrative & support | 2024 |
| Avma Group Limited | Hospitality | 2025 |
| AVN Interiors Limited | Construction | 2016 |
| Avna Accountants Limited | Professional & scientific | 2018 |
| AVO Electrical Ltd | Construction | 2017 |
| Avrit Ltd | Wholesale & retail | 2020 |
| AVS Accountants Ltd | Professional & scientific | 2022 |
| AVS Advisors Ltd | Professional & scientific | 2019 |
| AVS1 Ltd | Hospitality | 2022 |
| Avtar Construction Services Ltd | Construction | 2026 |
| Avvio Properties Ltd | Real estate | 2026 |
| AW Mortgage Solutions Limited | Financial services | 2018 |
| AWA Render Solution Ltd | Construction | 2023 |
| Awasi Tech Ltd | Information & communication | 2019 |
| Awayathome Ltd | Arts & recreation | 2026 |
| Awesomes Music Group Ltd | Information & communication | 2025 |
| Aweuro Limited | Administrative & support | 2022 |
| Axenzo Properties Ltd | Real estate | 2026 |
| Axis Civil Engineering Ltd | Construction | 2022 |
| Axton's Staircases Ltd | Manufacturing | 2025 |
| AY Investment Portfolio Ltd | Real estate | 2023 |
| AY Pictures Limited | Information & communication | 2022 |
| AYA Capital (Europe) Ltd | Professional & scientific | 2020 |
| Ayaan Properties Holding Ltd | Real estate | 2025 |
| Ayad Traffic Contractor Limited | Construction | 2018 |
| Ayan Logistics Ltd | Transport & logistics | 2025 |
| Ayano Trans Ltd | Transport & logistics | 2022 |
| AYG Freehold Ltd | Households | 2025 |
| AYG Properties Limited | Real estate | 2018 |
| Ayhan Kent Ltd | Other services | 2026 |
| Aylesford Electrical Contractors Limited | Construction | 1990 |
| Aylis & Elif Ltd | Transport & logistics | 2023 |
| Aymons Haven Ltd | Real estate | 2025 |
| AYO Digital Limited | Professional & scientific | 2024 |
| AYO DOT Ltd | Real estate | 2009 |
| Ayur Medical Ltd. | Health & social care | 2017 |