| A1 Majestic Park Homes Ltd | Real estate | 2025 |
| A1 Marble Direct Ltd | Construction | 2016 |
| A1 Minibus & Coach Ltd | Administrative & support | 2016 |
| A1 NEJ Contractors Limited | Construction | 2016 |
| A1 Safety Solutions Ltd | Manufacturing | 2025 |
| A1 Security Home Counties (U.K.) Ltd | Administrative & support | 1995 |
| A1 Solicitors Ltd | Professional & scientific | 2018 |
| A1 Superstore Luton Ltd | Wholesale & retail | 2026 |
| A1 Town & Country Ltd | Administrative & support | 2018 |
| A1 Tuition Centre Ltd | Education | 2026 |
| A1 Window Solutions Limited | Construction | 2011 |
| A10 Brokers Limited | Financial services | 2017 |
| A10 Logistics Ltd | Wholesale & retail | 2026 |
| A18 Global Limited | Wholesale & retail | 2025 |
| A2 Digital Ltd | Information & communication | 2025 |
| A24 Builders Ltd | Construction | 2023 |
| A29 Boutique Limited | Wholesale & retail | 2025 |
| A2A Global Trade Ltd | Wholesale & retail | 2025 |
| A2B Prime Services Limited | Transport & logistics | 2025 |
| A2I Natural Horsemanship Ltd | Agriculture & fishing | 2022 |
| A2SI Limited | Hospitality | 2026 |
| A2Z Cctv Limited | Wholesale & retail | 2021 |
| A2Z Cleaning UK Ltd | Administrative & support | 2022 |
| A2Z Drainage Services Ltd | Administrative & support | 2018 |
| A2Z Hajj Tours Limited | Administrative & support | 2026 |
| A2Z Online Bazaar Ltd | Wholesale & retail | 2025 |
| A3 Management Limited | Professional & scientific | 2018 |
| A3RP Ltd | Real estate | 2024 |
| A4 Motors & Autocare Limited | Wholesale & retail | 2026 |
| A4B Transport Limited | Transport & logistics | 2025 |
| A5K Properties Ltd | Real estate | 2024 |
| A7IGNED Ltd | Professional & scientific | 2025 |
| A@Z Computers Ltd | Other services | 2014 |
| AA & Logistics Ltd | Transport & logistics | 2019 |
| AA Aesthetix Ltd | Wholesale & retail | 2025 |
| AA and N Trading Ltd | Wholesale & retail | 2021 |
| AA Ashley Consultants Limited | Administrative & support | 2009 |
| AA Car Supermarket Limited | Wholesale & retail | 2025 |
| AA Codecrest Ltd | Wholesale & retail | 2025 |
| AA Coffee Ltd | Hospitality | 2025 |
| AA Electronics Ltd | Manufacturing | 2026 |
| AA Haulage Services Ltd | Transport & logistics | 2021 |
| AA Homeware Ltd | Wholesale & retail | 2026 |
| AA Legal Consultants Limited | Professional & scientific | 2023 |
| AA Motor Group Ltd | Wholesale & retail | 2026 |
| AA Parking Limited | Administrative & support | 2026 |
| AA Premium Chauffeurs Ltd | Transport & logistics | 2026 |
| AA Sandhu Transport Limited | Transport & logistics | 2025 |
| AA Tech Data Limited | Information & communication | 2017 |
| AA Tyre Centre Ltd | Wholesale & retail | 2015 |
| AA Web Marketing Ltd | Professional & scientific | 2023 |
| AA Xpress Services Ltd | Transport & logistics | 2024 |
| Aa&E Ltd | Construction | 2021 |
| Aa&H Sales Enterprise Ltd | Wholesale & retail | 2023 |
| AAA Car Cosmetic Repairs Ltd | Wholesale & retail | 2009 |
| AAA Container Self Storage Company Limited | Transport & logistics | 2021 |
| AAA Eatery Limited | Hospitality | 2026 |
| AAA G Rentals Limited | Real estate | 2025 |
| AAA Holdings (Luton) Ltd | Financial services | 2022 |
| AAA MOT Centre Limited | Wholesale & retail | 2025 |
| AAA Plastering Limited | Construction | 2018 |
| AAA Property Maintenance Limited | Manufacturing | 2014 |
| AAA Solicitors Ltd | Professional & scientific | 2021 |
| AAA Tiling Limited | Construction | 2016 |
| Aaaa Properties Ltd | Real estate | 2024 |
| Aaaad Ltd | Health & social care | 2023 |
| AAARD4 Ltd | Health & social care | 2021 |
| Aaaz Real Estate Ltd | Real estate | 2025 |
| AAC Transport Ltd | Manufacturing | 2026 |
| AAD Couriers Limited | Transport & logistics | 2025 |
| Aadams Travel Ltd | Transport & logistics | 2021 |
| Aaditya Logistics Ltd | Transport & logistics | 2025 |
| Aadroon Holdings Ltd | Financial services | 2021 |
| AAF Electrical Ltd | Construction | 2020 |
| Aaha Foods PVT Limited | Hospitality | 2025 |
| AAJ Express Limited | Transport & logistics | 2022 |
| AAK Consultants Ltd | Professional & scientific | 2022 |
| AAK Contractors Ltd | Construction | 2026 |
| AAK Investments Ltd | Other services | 2015 |
| AAK Service Company Ltd | Other services | 2014 |
| AAL Electrical Contractor Ltd | Construction | 2026 |
| Aaliah Limited | Health & social care | 2025 |
| Aalmaya Ltd | Real estate | 2025 |
| AAM Cars Ltd | Wholesale & retail | 2023 |
| AAM Distribution Ltd | Administrative & support | 2024 |
| Aamaal & Co Limited | Professional & scientific | 2021 |
| Aamaan Limited | Hospitality | 2020 |
| Aamb Services Ltd | Construction | 2022 |
| Aamin & Co Ltd | Transport & logistics | 2026 |
| Aanan Limited | Wholesale & retail | 2026 |
| AAR Hospitality Limited | Hospitality | 2024 |
| AAR Housing Ltd | Extraterritorial | 2024 |
| AAR Ventures Limited | Wholesale & retail | 2024 |
| Aariix Ltd | Financial services | 2026 |
| Aarna Flex Limited | Transport & logistics | 2023 |
| Aaron H Construction Ltd | Construction | 2017 |
| Aaron LEA Lets Limited | Real estate | 2019 |
| Aars Express Limited | Transport & logistics | 2022 |
| Aarushi's Property Ltd | Real estate | 2023 |
| Aarv Enterprises Ltd | Wholesale & retail | 2024 |