| ALI General Store Ltd | Wholesale & retail | 2019 |
| ALI Surgical Services Ltd. | Health & social care | 2009 |
| Alias Vehicle Solutions Limited | Administrative & support | 2014 |
| Alicemoira Ltd | Financial services | 2026 |
| Aligatou Ltd | Hospitality | 2024 |
| Align & Reform Limited | Arts & recreation | 2025 |
| Alignment Tools Ltd | Manufacturing | 2013 |
| Alii Brother's Limited | Wholesale & retail | 2025 |
| Alisha Anderson Ltd | Health & social care | 2018 |
| Alison Jackson Aesthetics Ltd | Health & social care | 2018 |
| Alistair Holroyd Limited | Construction | 2009 |
| Alistair Mann Ltd | Information & communication | 2008 |
| Aliun Superior Security Ltd | Wholesale & retail | 2020 |
| Aliyomi Solutions Ltd | Information & communication | 2010 |
| Alizad Transport and Financial Services Ltd | Transport & logistics | 2021 |
| Aliza’S Boutique Ltd | Wholesale & retail | 2023 |
| Aljon Engineering Co Limited | Administrative & support | 1993 |
| ALK Projects Ltd | Professional & scientific | 2024 |
| Alkaram Ltd | Information & communication | 2025 |
| Alkie Limited | Real estate | 1980 |
| ALL 4 One Consultants Limited | Arts & recreation | 2012 |
| ALL Aboard Transport Oldham Limited | Transport & logistics | 2025 |
| ALL About Weddings Group Ltd | Administrative & support | 2022 |
| ALL Build North West Limited | Construction | 2014 |
| ALL Complete Roofing Ltd | Construction | 2019 |
| ALL County Roofing Ltd | Construction | 2026 |
| ALL Day Energy Limited | Wholesale & retail | 2009 |
| ALL in One Accounting Solutions Ltd | Professional & scientific | 2021 |
| ALL in One Properties Ltd | Real estate | 2026 |
| ALL in One Tree and Garden Services Ltd | Administrative & support | 2020 |
| ALL in Roofing & Pressure Cleaning Ltd | Construction | 2026 |
| ALL Metals (Waste Management) Ltd | Water & waste | 2025 |
| ALL Project Flooring Ltd | Construction | 2020 |
| ALL Slates & Strip Limited | Water & waste | 2022 |
| ALL Surrey Roofing Limited | Construction | 2013 |
| ALL the Fours Plumbing Ltd | Construction | 2014 |
| ALL Things Teeth Limited | Wholesale & retail | 2020 |
| ALL WE DO Group Ltd | Administrative & support | 2025 |
| ALL World Tour Security Limited | Administrative & support | 2025 |
| ALL Wrapped UP Events Limited | Arts & recreation | 2020 |
| ALL4ONEGARMENT Ltd | Wholesale & retail | 2026 |
| ALL4SEASONSGM Ltd | Administrative & support | 2019 |
| Allameddine Medical Ltd | Professional & scientific | 2026 |
| Allan Hartwell Limited | Professional & scientific | 2010 |
| Allan Wood Limited | Health & social care | 2025 |
| Allegra Finance Ltd | Professional & scientific | 2019 |
| Allen Denton Developments Ltd | Construction | 2022 |
| Allen Ensed Group Limited | Wholesale & retail | 2022 |
| Allfire and Security Ltd | Construction | 2024 |
| Allforlove Childcare Limited | Health & social care | 2024 |
| Alliance and Recovery Care Group Ltd | Administrative & support | 2026 |
| Alliance Apparels Inspection Ltd | Manufacturing | 2018 |
| Alliance for Democracy and Freedom Party Ltd | Other services | 2019 |
| Alliance Property Consultant Limited | Households | 2022 |
| Allied Developers Ltd | Construction | 2019 |
| Allingan Investments Limited | Professional & scientific | 2025 |
| Allison & Carmel Limited | Real estate | 2005 |
| Allkind Deco Limited | Wholesale & retail | 2024 |
| Allonby IT Limited | Information & communication | 2014 |
| Allseas Global Logistics Limited | Transport & logistics | 2009 |
| Allseas Global Supply Chain Limited | Transport & logistics | 2013 |
| Allseas Shipping Company Limited | Transport & logistics | 2022 |
| Allsite Survey Limited | Construction | 2008 |
| Allton-Tech Systems Ltd | Construction | 2006 |
| Alma Plastering Limited | Administrative & support | 2016 |
| Alnoor Gift Shop Ltd | Wholesale & retail | 2024 |
| ALO UK Limited | Wholesale & retail | 1998 |
| Alpha Distribution International Ltd | Administrative & support | 2019 |
| Alpha Medical Imaging Ltd | Health & social care | 2013 |
| Alpha MNA Ltd | Real estate | 2016 |
| Alpha Mobiles Limited | Wholesale & retail | 2023 |
| Alpha Molecules Limited | Wholesale & retail | 2023 |
| Alpha Roofing (NW) Ltd | Construction | 2022 |
| Alphadex Limited | Wholesale & retail | 2020 |
| Alphamet Holdings Ltd | Households | 2016 |
| Alphatec AV Ltd | Other services | 2023 |
| Alphin Consulting Limited | Professional & scientific | 2018 |
| Alphin Pans Limited | Manufacturing | 1993 |
| Alphin SAR Holdings Limited | Financial services | 2022 |
| Alphin SAR Limited | Manufacturing | 2013 |
| Alphintek Limited | Information & communication | 2005 |
| Alpine Properties (2007) Limited | Real estate | 2007 |
| Alpine Rescue and Recovery Services Limited | Other services | 1992 |
| Alpine SB Investments Limited | Real estate | 2025 |
| Alpine SB Limited | Health & social care | 2024 |
| Alpine Trade Blinds Limited | Construction | 2017 |
| Alpineboy Ltd | Manufacturing | 2017 |
| Alrehmanfab Ltd | Wholesale & retail | 2025 |
| Alsafa Services Limited | Construction | 2017 |
| ALT Engineering Company Limited | Manufacturing | 1998 |
| ALT Hill Payments Ltd | Financial services | 2026 |
| ALT Through Time C.I.C. | Wholesale & retail | 2026 |
| Altcontrol Limited | Wholesale & retail | 2011 |
| Alternate IT Solutions Limited | Information & communication | 2008 |
| Altostratus Services Ltd | Information & communication | 2019 |
| Alumenium Ltd | Manufacturing | 2023 |
| Aluxo Ltd | Wholesale & retail | 2023 |
| Alveenalsalee Ltd | Wholesale & retail | 2025 |
| AM Architectural & Surveying Ltd | Construction | 2019 |
| AM Bluestone Ltd | Administrative & support | 2017 |