| Aa&S Mepani Limited | Real estate | 2019 |
| AAA & Co 7 Ltd. | Information & communication | 2015 |
| AAA Estates Limited | Real estate | 2018 |
| Aaak Ltd | Households | 2017 |
| AAC Solution Ltd | Construction | 2022 |
| Aadhya Limited | Information & communication | 2017 |
| Aadya Dhan Limited | Real estate | 2024 |
| Aadyum Ltd | Professional & scientific | 2025 |
| Aagam Builders Limited | Construction | 2019 |
| Aajway Cars Limited | Administrative & support | 2021 |
| Aakia Decor Ltd | Wholesale & retail | 2020 |
| AAL Estates Ltd | Real estate | 2020 |
| Aana London LP | | 2016 |
| Aanjaneya Limited | Hospitality | 2017 |
| Aariva Law Limited | Professional & scientific | 2026 |
| Aarna Holdings Limited | Financial services | 2019 |
| Aarnika Holdings Ltd | Health & social care | 2025 |
| Aashiv Limited | Real estate | 2017 |
| Aashkhar Limited | Real estate | 2025 |
| Aavaya Property Management Ltd | Real estate | 2022 |
| Aayurveda Limited | Wholesale & retail | 2025 |
| AB Accounting Ltd | Professional & scientific | 2009 |
| AB Dave Eyecare Ltd | Health & social care | 2015 |
| AB Healthcare Limited | Health & social care | 2013 |
| AB5 Properties Ltd | Real estate | 2021 |
| ABA Cars London Limited | Transport & logistics | 2018 |
| ABA Properties Limited | Real estate | 2000 |
| Abacus Building Services Limited | Construction | 2008 |
| Abba Father Cleaning & Maintenance Ltd | Real estate | 2017 |
| Abbey Court N3 Limited | Households | 2008 |
| Abbey Digitax LLP | | 2017 |
| Abbey Finance Limited | Financial services | 2014 |
| Abbey Road Properties of London Limited | Real estate | 2020 |
| Abbey Steel and Shearing Company Limited | Manufacturing | 1981 |
| Abbeyville Holdco 1 Limited | Real estate | 2024 |
| Abbeyville Holdco 2 Limited | Real estate | 2024 |
| Abbeyville Holdco 3 Limited | Real estate | 2024 |
| Abbeyville Holdco 4 Limited | Real estate | 2024 |
| Abbeyville Limited | Other services | 2021 |
| Abbzah Ltd | Arts & recreation | 2026 |
| ABC Happy BUS Service Limited | Transport & logistics | 2012 |
| Abconsultancy ETC Ltd | Education | 2023 |
| Aberdeen Cottages Limited | Real estate | 2011 |
| Aberdeen Parade Management Co. Limited | Real estate | 1984 |
| Aberno Ltd | Information & communication | 2020 |
| Abhyant Healthcare Ltd | Health & social care | 2024 |
| ABI Builders Ltd | Construction | 2016 |
| Abimax Ltd | Wholesale & retail | 2023 |
| Ableman & Ableman Limited | Professional & scientific | 2007 |
| Abott’S Cottage Limited | Real estate | 2023 |
| ABR Capital Partners Ltd | Financial services | 2020 |
| ABR Property Holdings Limited | Real estate | 2023 |
| Abracadabra Nursery Limited | Education | 2018 |
| Abracadabra Preschool Academy Limited | Education | 2012 |
| Abracadabra Preschool Limited | Education | 2024 |
| ABS Associates Limited | Professional & scientific | 2013 |
| ABS Cargo Services Limited | Transport & logistics | 2013 |
| ABS Group Investments Limited | Financial services | 2022 |
| Absher Estate One Limited | Real estate | 2025 |
| Absher Estate Two Limited | Real estate | 2025 |
| Absher Holding Limited | Financial services | 2025 |
| Absolute Assigned Policies Limited | Financial services | 1968 |
| Absolute Rise Limited | Information & communication | 2025 |
| Absolute Therapy Limited | Professional & scientific | 2014 |
| Abubble Digital Ltd | Other services | 2012 |
| Abypharm Ltd | Health & social care | 2011 |
| AC Couriers and Freight Services Limited | Transport & logistics | 2011 |
| AC Developments (London) Ltd | Construction | 2017 |
| Academy Electric Building Company (1931) Limited(The) | Construction | 1931 |
| Academy Fine Paintings Ltd | Wholesale & retail | 2011 |
| Acbd Limited | Administrative & support | 2008 |
| Access Media Technology Limited | Information & communication | 2025 |
| Accord Research Consultancy Limited | Information & communication | 2002 |
| Accountant on Board Limited | Professional & scientific | 2013 |
| Accountpro Services Limited | Professional & scientific | 2001 |
| ACD Driving Services Ltd | Transport & logistics | 2017 |
| Acdl Limited | Construction | 2018 |
| Ace Agriculture Ltd | Other services | 2022 |
| Ace Allizon Solutions Limited | Professional & scientific | 2007 |
| Ace Auto Products Ltd. | Wholesale & retail | 2009 |
| Ace Building & Construction Ltd | Construction | 2015 |
| Ace Building & Insulations Ltd | Construction | 2024 |
| Ace Business Holdings Ltd | Real estate | 2022 |
| Ace Courses Limited | Health & social care | 2023 |
| Ace Finance and Developments Ltd | Financial services | 2018 |
| Ace Guardian UK Limited | Education | 2026 |
| Ace of Face Aesthetics Ltd | Administrative & support | 2020 |
| Acellera Ltd | Information & communication | 2006 |
| Acepro Maintenance Services Ltd | Construction | 2026 |
| ACK Media Consulting Limited | Information & communication | 2026 |
| ACL London Ltd | Construction | 2020 |
| Acme Homes Limited | Real estate | 2019 |
| Acoustic Demolition Services Limited | Construction | 2015 |
| Acquah Lodge Limited | Health & social care | 2017 |
| Acquappesa Limited | Administrative & support | 2014 |
| Acre Building Consultants Ltd | Administrative & support | 2012 |
| Acre House Developments Limited | Construction | 1993 |
| Active Alpaca Limited | Professional & scientific | 2019 |
| Active Sports Construction Ltd | Construction | 2018 |
| Activespace (Richings Park) Ltd | Arts & recreation | 2026 |