| Avellino Flooring Ltd | Wholesale & retail | 2004 |
| Avenue Artistes Limited | Arts & recreation | 1964 |
| Avenue Audio Limited | Arts & recreation | 2012 |
| Avenue Electrical Limited | Construction | 2003 |
| Avenue Estates Management Limited | Real estate | 2020 |
| AVENUE13 Limited | Real estate | 2021 |
| Avenues College Ltd | Education | 2016 |
| Averona Group Ltd | Construction | 2022 |
| Avery Accident Repair Specialists Ltd | Wholesale & retail | 2013 |
| Avery Homes RH Limited | Extraterritorial | 2015 |
| AVG Stores Limited | Wholesale & retail | 2015 |
| Aviation Engineering Ltd | Professional & scientific | 2024 |
| Avid Removals & Cleaning Service Ltd | Transport & logistics | 2022 |
| Avington House Management Company Limited | Households | 1995 |
| Avington Land Estate Limited | Real estate | 2024 |
| Avington Park Accommodation Limited | Real estate | 2022 |
| Avington Park Estate Limited | Real estate | 2020 |
| Avinit Group Ltd | Wholesale & retail | 2020 |
| Avion Training and Consultancy Ltd | Other services | 2011 |
| Avior Care Ltd | Extraterritorial | 2017 |
| Avioria Ltd | Wholesale & retail | 2025 |
| Avisank Ltd | Health & social care | 2014 |
| Avision Brickwork Ltd | Construction | 2024 |
| Avko Industrial Limited | Manufacturing | 2019 |
| Avko Interior Limited | Manufacturing | 2014 |
| Avko Limited | Manufacturing | 1997 |
| Avko Marine Limited | Manufacturing | 2017 |
| Avlan Court Limited | Households | 1975 |
| AVN Yacht Management Limited | Manufacturing | 2026 |
| Avoleux Consultancy Ltd | Professional & scientific | 2022 |
| Avon Care Holdings Limited | Health & social care | 2020 |
| Avon Court (Netley) Limited | Other services | 1968 |
| Avondale Residencies Limited | Real estate | 1999 |
| Avonglen Limited | Professional & scientific | 2003 |
| AVP Logistics Ltd | Transport & logistics | 2025 |
| Avrali Ltd | Information & communication | 2025 |
| AVV Transport Ltd | Transport & logistics | 2026 |
| AW Blissful Creations Ltd | Professional & scientific | 2025 |
| Awais Shah Ltd | Wholesale & retail | 2025 |
| Awakenode Ltd | Information & communication | 2022 |
| Award Building Contractors Ltd | Construction | 2019 |
| Award Environmental Consultants Limited | Administrative & support | 2015 |
| Awarevue Limited | Information & communication | 2024 |
| Awaritse International UK Ltd | Real estate | 2024 |
| Awaro Ltd | Wholesale & retail | 2019 |
| Awck Projects Limited | Manufacturing | 2019 |
| AWE Contractors Ltd | Construction | 2014 |
| AWE Investments Limited | Real estate | 2023 |
| AWJ Limted Limited | Transport & logistics | 2019 |
| AWK Marine Services Ltd | Manufacturing | 2025 |
| AWK Marine Shop Ltd | Wholesale & retail | 2025 |
| Awkwardly Social Media Limited | Professional & scientific | 2026 |
| AWL Engineering Solutions Ltd | Professional & scientific | 2021 |
| AWS Heating Engineers Limited | Administrative & support | 2012 |
| AWS Trampers Ltd | Construction | 2023 |
| Awsruxley Ltd | Construction | 2024 |
| AWZ Homes Ltd | Real estate | 2020 |
| Axia Software Solutions Private Limited | Information & communication | 2023 |
| Axial Lifts Ltd | Professional & scientific | 2025 |
| Axiom Controls Limited | Administrative & support | 2004 |
| Axiom Training Ltd | Education | 2025 |
| Axis CLC Group Limited | Professional & scientific | 1985 |
| Axis Drive Ltd | Wholesale & retail | 2026 |
| Axisense Ltd | Professional & scientific | 2025 |
| Axiym Accounting Ltd | Professional & scientific | 2024 |
| Axolotl Capital Holdings Limited | Information & communication | 2022 |
| Axsis Managed Services Ltd | Information & communication | 2025 |
| Axton Limited | Information & communication | 2003 |
| AYA Fabrics Ltd | Wholesale & retail | 2026 |
| AYA Home and Soap Company Limited | Manufacturing | 2016 |
| Ayan Darius Ltd | Transport & logistics | 2026 |
| Ayla Soso Ltd | Transport & logistics | 2024 |
| Aylia Enterprise Ltd | Wholesale & retail | 2024 |
| Aylin Logistics Ltd | Transport & logistics | 2025 |
| Ayodam Ltd | Transport & logistics | 2020 |
| AYT Exec Services Ltd | Transport & logistics | 2025 |
| AYU Health Ltd | Wholesale & retail | 2019 |
| AYU Healthcare Limited | Wholesale & retail | 2014 |
| Ayza Properties Ltd | Real estate | 2021 |
| AZ Exotic VET Ltd | Professional & scientific | 2023 |
| AZB Ltd | Administrative & support | 2019 |
| AZE Cars Ltd | Transport & logistics | 2026 |
| Azlet Holding Limited | Real estate | 2024 |
| Azmar Kebabs Limited | Hospitality | 2026 |
| Azpectra Limited | Information & communication | 2026 |
| Azra Aesthetics Ltd | Health & social care | 2018 |
| Aztax Consulting Limited | Real estate | 2006 |
| Aztec Fascias Limited | Construction | 2006 |
| Azure Capital (Dorchester) Ltd | Construction | 2021 |
| Azure People Limited | Information & communication | 2025 |
| Azure Shuttle Services Ltd | Other services | 2023 |
| Azure Strategic Estates Ltd | Transport & logistics | 2025 |
| Azureus Homes Limited | Construction | 2015 |
| B & a Logistics Limited | Transport & logistics | 2005 |
| B & C Property UK Limited | Real estate | 1970 |
| B & C Reconditioning (Gears) Limited | Manufacturing | 2003 |
| B & H Khaira Properties Limited | Construction | 2009 |
| B & S Salek Ltd | Construction | 2019 |
| B & W Supreme Services Limited | Construction | 2024 |
| B and B Homes Southern Ltd | Construction | 2023 |