| Alexander Accessories Limited | Manufacturing | 2002 |
| Alexanders Property Services Limited | Real estate | 2013 |
| Alexia Claire Ltd | Wholesale & retail | 2020 |
| Alexis Autos Limited | Wholesale & retail | 2021 |
| Alfred Foster Rostron Limited | Construction | 2011 |
| Alidor Ltd | Wholesale & retail | 2025 |
| Align & Grow Limited | Professional & scientific | 2023 |
| Aligne Wellness Studios Ltd | Arts & recreation | 2025 |
| Aligned Living Limited | Other services | 2025 |
| Alistair Prince Advisory Limited | Professional & scientific | 2024 |
| ALL About Desserts Ltd | Manufacturing | 2016 |
| ALL Courts Limited | Construction | 2001 |
| ALL England Netball Association Limited | Arts & recreation | 1983 |
| ALL Saints View Management Company Limited | Households | 2014 |
| Allami Consulting Ltd | Professional & scientific | 2026 |
| Allexton Homes Ltd | Construction | 2025 |
| Alliance (CS) Limited | Administrative & support | 1998 |
| Alliance Integrated Systems Limited | Administrative & support | 2001 |
| Allstar Climbing Ltd | Arts & recreation | 2026 |
| Alltar Limited | Real estate | 2023 |
| Allure Beauty Quorn Limited | Other services | 2021 |
| Allure Nails Loughborough Ltd | Other services | 2023 |
| Ally 23 Limited | Real estate | 2017 |
| Alm-Uk Ltd | Professional & scientific | 2019 |
| Alma Services Limited | Health & social care | 2023 |
| Alma Trans. Ltd | Transport & logistics | 2019 |
| Almanac Designs Limited | Wholesale & retail | 2023 |
| Almas Properties Ltd | Real estate | 2021 |
| Alpha and Omega Signals Limited | Education | 2025 |
| Alpha Power Cleaners Limited | Administrative & support | 2009 |
| Alphas Healthcare Limited | Health & social care | 2024 |
| Alstec Ltd | Construction | 2022 |
| Altapage Productions Limited | Information & communication | 2012 |
| Alteka Solutions Limited | Manufacturing | 2020 |
| Alteration Company (Midlands) Limited | Wholesale & retail | 2022 |
| Alternative Cooling Solutions Limited | Construction | 2001 |
| Altip Limited | Transport & logistics | 2013 |
| Aluminium Glazing Specialists Limited | Manufacturing | 2025 |
| Alway Loughborough Limited | Manufacturing | 1985 |
| Always Mind Ltd | Education | 2022 |
| AM Advanced Engineering Ltd | Manufacturing | 2024 |
| AM Brands International Ltd | Wholesale & retail | 2023 |
| AM1 Global Trade Ltd | Professional & scientific | 2025 |
| AM7 Sports Ltd | Arts & recreation | 2025 |
| Amafhh Healthcare Limited | Health & social care | 2008 |
| Amaj Health Services Ltd | Transport & logistics | 2023 |
| Amanda Sutcliffe Conveyancing Ltd | Professional & scientific | 2025 |
| Amara Healthcare Partners Ltd | Health & social care | 2025 |
| Amarog Ltd | Administrative & support | 2017 |
| Amarsat Ltd | Financial services | 2019 |
| Amateur Swimming Federation of Great Britain Limited | Arts & recreation | 2001 |
| Amazing Grace Excel Company Limited | Transport & logistics | 2020 |
| Amba Developments Limited | Construction | 2025 |
| Amba Estates Ltd | Professional & scientific | 2017 |
| Ambassador Homes (Notts) Limited | Real estate | 2025 |
| Amber Analytical Services Limited | Professional & scientific | 2020 |
| Amber Taxis Limited | Extraterritorial | 2016 |
| Ambience Bistro and Brews Ltd | Hospitality | 2025 |
| Ambience Creative Designs LLP | | 2016 |
| Ambience Designs International Ltd | Manufacturing | 2024 |
| Ameerah Enterprise Ltd | Hospitality | 2024 |
| Amelen Ltd | Real estate | 2025 |
| Amici Catering Limited | Hospitality | 2019 |
| Amirul Indian Cuisine Ltd | Hospitality | 2016 |
| Amirul Quorn Limited | Hospitality | 2021 |
| AMJ Properties Loughborough Ltd | Real estate | 2026 |
| AMK Investment Property Ltd | Real estate | 2025 |
| Amliya Properties Ltd | Real estate | 2022 |
| Amore the SET Ltd | Wholesale & retail | 2025 |
| Amour Studios Limited | Other services | 2016 |
| Amsden & Young Ltd | Professional & scientific | 2012 |
| Amsden Young Ltd | Information & communication | 2021 |
| Amsk Solutions Ltd | Information & communication | 2020 |
| Amss Property Ltd | Real estate | 2024 |
| Amss Reset Ltd | Education | 2024 |
| AMT Loughborough Ltd | Wholesale & retail | 2022 |
| AMW Homes Limited | Construction | 2009 |
| AMW Kitchens Ltd | Construction | 2014 |
| ANA Perry Limited | Professional & scientific | 2020 |
| Anabiya Tech Ltd | Wholesale & retail | 2024 |
| Anaiya Developments Limited | Real estate | 2019 |
| Ancaster Sports Limited | Arts & recreation | 2022 |
| Anchor Revenue Limited | Professional & scientific | 2026 |
| AND for the Love of Crystals Limited | Wholesale & retail | 2021 |
| Andibee Ltd | Professional & scientific | 2016 |
| Andrew East Ltd | Real estate | 2005 |
| Andrew Jones Consulting Limited | Professional & scientific | 2022 |
| Andrew Warren Associates Limited | Hospitality | 2019 |
| Andrews & Akam Consulting Ltd | Professional & scientific | 2019 |
| Andross Limited | Transport & logistics | 2014 |
| Andy Abraham Limited | Extraterritorial | 2010 |
| Andy Frizzell Limited | Construction | 2002 |
| Andy Gray Sports Consultancy Limited | Professional & scientific | 2013 |
| Andy Wood Projects Limited | Professional & scientific | 2010 |
| Andy Wright Ltd | Professional & scientific | 2011 |
| Anely Elite Cleaning Ltd | Administrative & support | 2026 |
| Angel & Co Paradise Ltd | Real estate | 2025 |
| Angel Fernandez Limited | Arts & recreation | 2020 |
| Angela Hannah Ltd | Health & social care | 2016 |
| Angell Mallinder Limited | Financial services | 2009 |