| Ansbrook Limited | Financial services | 2022 |
| Ansh Consultancy Services Limited | Information & communication | 2025 |
| Ansr Ltd | Real estate | 2025 |
| Anstera Tax Limited | Professional & scientific | 2017 |
| ANT Education Limited | Education | 2017 |
| ANT Seafood Limited | Wholesale & retail | 2020 |
| ANT Shuttering Ltd | Construction | 2019 |
| Antaeus Virtus Limited | Information & communication | 2011 |
| Antal Shipping Limited | Transport & logistics | 2004 |
| Antalica Ltd | Professional & scientific | 2025 |
| Antanas Construction Limited | Construction | 2026 |
| Antarctic Contracts Ltd | Other services | 2024 |
| Antarctica Global Ltd | Wholesale & retail | 2024 |
| Antaz Limited | Manufacturing | 2005 |
| Antelope Worldwide Ltd | Professional & scientific | 2009 |
| Anthana Clinic Limited | Other services | 2024 |
| Anthea Fine Arts Limited | Wholesale & retail | 2020 |
| Anthony Court Limited | Households | 1986 |
| Anthony James Electrical Ltd | Construction | 2020 |
| Anthony Nash Financial Advice Ltd | Financial services | 2026 |
| Anthurium Properties Ltd | Real estate | 2019 |
| Anti-Block Drainage Ltd | Water & waste | 2019 |
| Anti-Racist Alliance Trust | Professional & scientific | 2000 |
| Antimie Ltd | Construction | 2019 |
| Antique House Limited | Wholesale & retail | 2009 |
| Antistatic Limited | Extraterritorial | 1998 |
| Antler Hair & Beauty Limited | Other services | 2010 |
| Antodeea Trans Ltd | Transport & logistics | 2024 |
| Antonio Rosa Partnership Ltd | Construction | 2026 |
| Antonio Trans Ltd | Transport & logistics | 2016 |
| Antonucci Limited | Wholesale & retail | 2024 |
| Antony Jones Limited | Professional & scientific | 2004 |
| Antoro Ltd | Construction | 2021 |
| Antotrans Ltd | Transport & logistics | 2016 |
| Anty@Stoppelli Limited | Real estate | 2017 |
| Antya Enterprise Ltd | Other services | 2024 |
| Antyeshti Limited | Other services | 2024 |
| Anuco Limited | Construction | 2022 |
| Anujas Bakehouse Ltd | Manufacturing | 2020 |
| Anumanth Management Ltd | Real estate | 2015 |
| Anuri Holdings Limited | Real estate | 2021 |
| Anushka Consulting Limited | Professional & scientific | 2004 |
| Anushka's Drama School Ltd | Arts & recreation | 2025 |
| Anva CM Ltd | Construction | 2024 |
| Anvi Estates Ltd | Real estate | 2022 |
| Anvil Films Limited | Information & communication | 1998 |
| Anvk Ltd | Real estate | 2025 |
| Anwar Property and Investments Limited | Extraterritorial | 2017 |
| ANX Properties Ltd | Real estate | 2018 |
| Anxpert Consulting Ltd | Professional & scientific | 2023 |
| ANY Capital Investments Limited | Financial services | 2019 |
| ANY Time Electrician Limited | Construction | 2021 |
| Anya Tech Ltd | Information & communication | 2018 |
| Anyaa Event Management Ltd | Other services | 2012 |
| Anyfeast Limited | Hospitality | 2022 |
| Anyfield Limited | Hospitality | 2005 |
| Anytime Drinks Limited | Wholesale & retail | 2024 |
| Anytime Motion Pictures Limited | Information & communication | 2023 |
| Anytimedelivery Ltd | Wholesale & retail | 2018 |
| Anywell Health UK Ltd | Health & social care | 2025 |
| Anyy Architects Limited | Professional & scientific | 2023 |
| Anzan Limited | Education | 2011 |
| Anzl Limited | Financial services | 2017 |
| Anzor Autos Ltd | Wholesale & retail | 2011 |
| AO London Investments Limited | Real estate | 2025 |
| AOA86 Limited | Real estate | 2017 |
| AOB of London Limited | Wholesale & retail | 2021 |
| AOJ Restaurants Ltd | Hospitality | 2009 |
| AOM Recruitment Ltd | Administrative & support | 2024 |
| Aonet Ltd | Professional & scientific | 2019 |
| Aopp Education Limited | Education | 2022 |
| Aopp Limited | Health & social care | 2021 |
| AP & P Consultants Limited | Professional & scientific | 2026 |
| AP & Sons Ltd | Wholesale & retail | 2022 |
| AP 91 Ltd | Health & social care | 2024 |
| AP and SP Properties Ltd | Real estate | 2017 |
| AP Beauty Salon Ltd | Other services | 2026 |
| AP Best Solution Ltd | Construction | 2014 |
| AP Ceilings&Partitions Ltd | Manufacturing | 2019 |
| AP Cosmetics Ltd | Wholesale & retail | 2025 |
| AP Cubed UK Limited | Manufacturing | 2023 |
| AP Homeo Nutri Care Ltd | Health & social care | 2025 |
| AP Jewels Limited | Wholesale & retail | 2024 |
| AP Locum Connect Ltd | Health & social care | 2018 |
| AP Mart Ltd | Wholesale & retail | 2026 |
| AP Projects Ltd | Real estate | 2017 |
| AP Talbot Ltd | Real estate | 2019 |
| AP Wood Flooring Ltd | Construction | 2026 |
| AP Yogi Limited | Administrative & support | 2021 |
| Ap&H Ltd | Construction | 2025 |
| AP3 Advisory Services Ltd | Professional & scientific | 2019 |
| AP3 Capital & Advisory Services Limited | Professional & scientific | 2021 |
| Apacgragon Limited | Real estate | 2023 |
| Apar Limited | Households | 1999 |
| Apara Fashion Limited | Wholesale & retail | 2024 |
| Aparaschivei P&A Limited | Construction | 2023 |
| APB Asset Management Limited | Administrative & support | 2023 |
| APC Capital 1 Limited | Real estate | 2020 |
| APC Capital 6 Limited | Real estate | 2020 |
| APC Capital 9 Limited | Real estate | 2021 |