| Amber Safetywear Ltd | Wholesale & retail | 2010 |
| Amberdene Management Company Limited | Households | 1992 |
| Ambience Homes & Facilities Managememt UK Limited | Real estate | 2024 |
| Ambient Film Ltd | Information & communication | 2008 |
| Ambio Property Limited | Real estate | 2026 |
| Amco Agency Limited | Administrative & support | 2012 |
| AMD GP Services Ltd | Health & social care | 2026 |
| AMD Investments Holdings Ltd | Financial services | 2026 |
| Amdy Ltd | Hospitality | 2026 |
| AMF Project Ltd | Information & communication | 2020 |
| AMG Painting Ltd | Construction | 2025 |
| AMG Rail Limited | Construction | 2018 |
| AMI & JAY Properties Limited | Real estate | 2021 |
| AMI Electrics Ltd | Construction | 2014 |
| Amin Halal Meat Limited | Wholesale & retail | 2023 |
| Amirh Ltd | Real estate | 2017 |
| Amirhea Ltd | Real estate | 2012 |
| Amity Services Ltd | Professional & scientific | 2020 |
| AML Transport Services Ltd | Transport & logistics | 2018 |
| AMM Carrier Ltd | Transport & logistics | 2022 |
| Amma Curry Ltd | Hospitality | 2020 |
| Amma Garages Ltd | Wholesale & retail | 2022 |
| Ammisol Ltd | Information & communication | 2023 |
| Amna Mart Ltd | Wholesale & retail | 2026 |
| Amneh Grill House (UK) Ltd | Hospitality | 2025 |
| AMO (2020) Limited | Real estate | 2020 |
| AMO Electrical Services Limited | Construction | 2011 |
| AMO Property Limited | Real estate | 2018 |
| Amo-Z Limited | Other services | 2017 |
| Amora Timeless Ltd | Wholesale & retail | 2025 |
| Ampardi MCR Limited | Health & social care | 2017 |
| Ampio Digital Ltd | Information & communication | 2024 |
| AMS Fitters Ltd | Construction | 2023 |
| Amseymour Consulting Limited | Information & communication | 2009 |
| Amsr Healthcare Ltd | Health & social care | 2010 |
| Amure Medical Ltd | Health & social care | 2026 |
| Amwt Limited | Professional & scientific | 2009 |
| AMY Cohen Limited | Administrative & support | 2021 |
| AN UK Courses Limited | Education | 2023 |
| Anakha Limited | Professional & scientific | 2007 |
| Analytical Advantage UN Limited | Professional & scientific | 2023 |
| Anant Growth Limited | Information & communication | 2025 |
| Anant Solutions Limited | Information & communication | 2023 |
| Ananya Construction Limited | Construction | 2026 |
| ANATOLIS16 Ltd | Wholesale & retail | 1991 |
| Anca Building Services Ltd | Construction | 2016 |
| Anca.Bogdan Transport Limited | Transport & logistics | 2018 |
| Ancient Texts Ltd | Wholesale & retail | 2024 |
| Andark Limited | Real estate | 2021 |
| Anddservices Ltd | Construction | 2024 |
| Andreescu AYB Ltd | Transport & logistics | 2022 |
| Andrei&Nyk Construction Ltd | Construction | 2025 |
| Andrew Barr Knitwear Limited | Wholesale & retail | 2001 |
| Andrew Cumming Wealth Management Limited | Financial services | 2014 |
| Andrew Farkas Limited | Construction | 2003 |
| Andrew Griffiths Online Limited | Information & communication | 2011 |
| Andrew's Home Design Limited | Construction | 2016 |
| Andro Fire Protection Ltd | Construction | 2024 |
| Andronic Formwork Ltd | Construction | 2015 |
| Andyamb Ltd | Construction | 2024 |
| ANE Global Limited | Administrative & support | 2025 |
| ANG Medical Limited | Health & social care | 2016 |
| Angel City Ltd | Other services | 2019 |
| Angel Faces Beauty Ltd | Other services | 2025 |
| Angel Invest Limited | Real estate | 2025 |
| Angel Limited | Manufacturing | 1994 |
| Angel Support Living (S.W) Limited | Health & social care | 2026 |
| Angel Tiara Limited | Wholesale & retail | 2023 |
| Angel View Estates Ltd | Real estate | 2025 |
| Angela Management Consultancy Ltd | Professional & scientific | 2012 |
| Angela Property Management Limited | Real estate | 2019 |
| Angelic Ingredients Ltd | Manufacturing | 2024 |
| Angelo Projects Limited | Wholesale & retail | 2018 |
| Angelos Dajkokeri Ltd | Real estate | 2024 |
| Angels Academylondon Limited | Other services | 2019 |
| Angels Salons (UK) Limited | Other services | 2011 |
| Angle House Cricklewood Ltd | Health & social care | 2018 |
| Angle House Ealing Ltd | Health & social care | 2014 |
| Angle House Education Ltd | Education | 2018 |
| Angle House Foundation | Professional & scientific | 2011 |
| Angle House Goffs Oak Ltd | Health & social care | 2018 |
| Angle House Harrow Ltd | Health & social care | 2020 |
| Angle House Highgate Ltd | Health & social care | 2022 |
| Angle House Limited | Other services | 2013 |
| Angle House Oral Healthcare Ltd | Wholesale & retail | 2020 |
| Angle House Oral Surgery Ltd | Health & social care | 2017 |
| Angle House Orthodontics Islington Limited | Health & social care | 2014 |
| Angle House Orthodontics Limited | Professional & scientific | 2013 |
| Anglecare Wellness Ltd | Health & social care | 2024 |
| ANGLES9 Ltd | Real estate | 2020 |
| Anglo International Investments Ltd | Wholesale & retail | 2011 |
| Anglo-Dal Limited | Wholesale & retail | 1939 |
| ANH Property Ltd | Real estate | 2021 |
| Anias House Ltd | Information & communication | 2025 |
| Animatics Films Ltd | Information & communication | 2019 |
| Aniren Anaesthesia Ltd | Health & social care | 2020 |
| Anjaney Systems Limited | Information & communication | 2021 |
| Anjia Limited | Real estate | 2019 |
| Ankit Govind Photography Ltd | Information & communication | 2015 |
| Anmi Investments Limited | Real estate | 2025 |