| Alex Bishop Guitars Limited | Manufacturing | 2023 |
| Alex Bovey Consultancy Limited | Information & communication | 2008 |
| Alex Burridge Electrical Limited | Construction | 2017 |
| Alex C&C Healthcare Ltd | Administrative & support | 2020 |
| Alex C&C Training Ltd | Education | 2023 |
| Alex Carlton DEV Limited | Information & communication | 2022 |
| Alex Cars Bristol Ltd | Wholesale & retail | 2018 |
| Alex Casado Limited | Professional & scientific | 2022 |
| Alex Cerio Limited | Administrative & support | 2016 |
| Alex Ferguson Ltd | Financial services | 2022 |
| Alex Flower Electrical Ltd | Construction | 2024 |
| Alex FRY Rental Properties Ltd | Real estate | 2016 |
| Alex Hall Personal Training Ltd | Education | 2025 |
| Alex Kennedy Consultancy Limited | Professional & scientific | 2024 |
| Alex Murray Golf Limited | Wholesale & retail | 2007 |
| Alex Niven Makeup Ltd | Other services | 2022 |
| Alex Price Ltd | Manufacturing | 2020 |
| Alex Richmond Limited | Real estate | 2022 |
| Alex Stoneman Photography Ltd | Professional & scientific | 2025 |
| Alex Todd Golf Ltd | Wholesale & retail | 2025 |
| Alex Vail Cinematography Ltd | Information & communication | 2019 |
| Alexander Consulting Services Ltd | Information & communication | 2026 |
| Alexander Gallery Ltd | Arts & recreation | 2002 |
| Alexander Hastings Limited | Real estate | 2006 |
| Alexander Heating & Plumbing Limited | Construction | 2024 |
| Alexander Homes and Developments Limited | Construction | 2017 |
| Alexander House Management Company (Cirencester) Limited | Real estate | 2015 |
| Alexander MAY Property Holdings Limited | Financial services | 2023 |
| Alexander MAY Property Limited | Real estate | 2008 |
| Alexander Milne Estates Limited | Real estate | 2003 |
| Alexander Shaw Limited | Professional & scientific | 2010 |
| Alexander Smith Ltd | Information & communication | 2020 |
| Alexander Telecoms Consulting Ltd | Information & communication | 2017 |
| Alexander William Consulting Ltd | Administrative & support | 2023 |
| Alexandra & Hillyfields Vets Ltd | Extraterritorial | 2009 |
| Alexandra Court Management Company Limited | Households | 1987 |
| Alexandra Court West Park Management Company Limited(The) | Households | 1983 |
| Alexandra Gate Management Limited | Households | 1989 |
| Alexandra Hair Limited | Other services | 2026 |
| Alexandra Homes (Bristol) Limited | Health & social care | 2004 |
| Alexandra Koumis Ltd | Professional & scientific | 2018 |
| Alexandra Powell Aesthetics Limited | Health & social care | 2022 |
| Alexandra Road Clevedon Management Ltd | Households | 2020 |
| Alexandra Rose (Bath) Limited | Wholesale & retail | 2021 |
| Alexandru Ciprian Eugen Alexandru Ltd | Wholesale & retail | 2025 |
| Alexem Limited | Professional & scientific | 2018 |
| Alexstancu Transport Ltd | Transport & logistics | 2024 |
| ALEXTRA22 Limited | Wholesale & retail | 2025 |
| Alfa Investment Management Ltd | Other services | 2010 |
| Alfa Property Partners Ltd | Real estate | 2019 |
| Alfa Recovery Ltd | Transport & logistics | 2024 |
| Alfa Secure Services Ltd | Administrative & support | 2019 |
| Alfa Technology Consulting Ltd | Information & communication | 2018 |
| Alfa Travel Solutions Ltd | Transport & logistics | 2022 |
| Alfadlouni Ltd | Real estate | 2025 |
| Alfasher Market Limited | Wholesale & retail | 2025 |
| Alfatek LP | | 2012 |
| Alfie & Bella Limited | Administrative & support | 2012 |
| Alfin PDS Ltd | Transport & logistics | 2011 |
| Alfred Court Property Management Limited | Households | 1988 |
| Alfresco Bars Ltd | Wholesale & retail | 2025 |
| Alfresco Drinks Limited | Wholesale & retail | 1996 |
| Alfresco Food Bristol Ltd | Hospitality | 2025 |
| Alfu Limited | Manufacturing | 2019 |
| Alfu Mega Ltd | Wholesale & retail | 2020 |
| Alfu U.K Ltd | Wholesale & retail | 2020 |
| Algorithmic Edge Ltd | Information & communication | 2023 |
| Algorithmica Solutions Ltd | Information & communication | 2016 |
| Algosoup Ltd | Information & communication | 2026 |
| Algotechnic Ltd | Information & communication | 2012 |
| ALH Holdings Limited | Professional & scientific | 1986 |
| Alhawa Services Ltd | Transport & logistics | 2025 |
| ALI & Kitty Limited | Wholesale & retail | 2018 |
| ALI Baba Hummus Ltd | Manufacturing | 2019 |
| ALI Baba Range Ltd | Manufacturing | 2019 |
| ALI Damion Designs Limited | Wholesale & retail | 2026 |
| ALI Electrical Installations Ltd | Construction | 2013 |
| ALI General Store and OFF Licence Ltd | Wholesale & retail | 2025 |
| ALI Hassan Corporation Ltd | Wholesale & retail | 2025 |
| Ali's Country Kitchen Ltd | Hospitality | 2022 |
| Ali's CP2 Limited | Hospitality | 2025 |
| Ali-Ways Independence Training Ltd | Education | 2013 |
| Aliali Courier Service Ltd | Transport & logistics | 2026 |
| Alibah Limited | Professional & scientific | 2006 |
| Alice Heraud Ltd | Professional & scientific | 2026 |
| Alice Menter Ltd | Manufacturing | 2011 |
| Alice Properties Ltd | Hospitality | 2003 |
| Alice Tait Ltd | Arts & recreation | 2024 |
| Alide Developments Limited | Construction | 2012 |
| Aliden Services Limited | Other services | 2015 |
| Alidena LP | | 2014 |
| Alienbrain Ltd | Information & communication | 2016 |
| Align Intelligence Ltd | Professional & scientific | 2024 |
| Align Physical Therapy Ltd | Health & social care | 2026 |
| Alignus Ltd | Information & communication | 2024 |
| Alignwell Studio Ltd | Other services | 2025 |
| Aligon LP | | 2017 |
| Aliign Capital Ltd | Real estate | 2025 |
| Alimam-Hampton Limited | Professional & scientific | 2023 |
| Alimo Care Ltd | Health & social care | 2010 |