| Autonomous AI Ltd | Information & communication | 2026 |
| Autowash Detailing Specialists Limited | Extraterritorial | 2010 |
| Autowmotive Installations Ltd | Wholesale & retail | 2025 |
| AV Sedations Ltd | Health & social care | 2000 |
| AVA Group Limited | Construction | 2020 |
| Avani Modular Housing Limited | Construction | 2025 |
| Avani Technologies Ltd | Information & communication | 2014 |
| Avanti Probate and Estate Services Ltd | Professional & scientific | 2021 |
| Avara Clothing Ltd | Wholesale & retail | 2025 |
| Avas Consulting Ltd | Information & communication | 2016 |
| Avatar Electrical Limited | Construction | 2009 |
| Avelyn & Gill Ltd | Health & social care | 2016 |
| AVI & Alex Limited | Construction | 2016 |
| Avista Residential Care Limited | Health & social care | 2023 |
| AVJ Electrical Ltd | Construction | 2014 |
| Avkdigital Ltd | Information & communication | 2022 |
| AVM Holding Limited | Households | 2019 |
| AVT Special Projects Ltd | Professional & scientific | 2024 |
| AW Marine & Sons Ltd | Administrative & support | 2011 |
| Awakenings Ltd | Professional & scientific | 2002 |
| AWG Rentals Limited | Wholesale & retail | 2013 |
| AWS Business Consultants Limited | Professional & scientific | 2013 |
| Axguru Limited | Extraterritorial | 2017 |
| Axis IQ Ltd | Professional & scientific | 2022 |
| Axis Track Services Limited | Administrative & support | 2012 |
| Axium Construction Ltd | Construction | 2026 |
| Ayaana Spice Ltd | Hospitality | 2020 |
| Ayah Beauty London Limited | Wholesale & retail | 2024 |
| Ayan Medics Limited | Health & social care | 2015 |
| Ayan Traders Ltd | Wholesale & retail | 2023 |
| Ayladental Limited | Health & social care | 2022 |
| Aymac Ltd | Wholesale & retail | 2020 |
| Ayzee Ltd | Administrative & support | 2026 |
| Azlaia Ltd | Professional & scientific | 2025 |
| Aztec Garden Shows Limited | Other services | 2001 |
| B & L Taxi Rental Ltd | Administrative & support | 2022 |
| B & M Accountants Ltd | Financial services | 2017 |
| B E Golds Investment Ltd | Real estate | 2024 |
| B Tandoori Ltd | Hospitality | 2024 |
| B Van Niekerk Limited | Health & social care | 2022 |
| B&O Partners Limited | Other services | 2016 |
| B&S Pharma Ltd | Health & social care | 2023 |
| B-Home Tendering & Contracts Ltd | Construction | 2024 |
| B.A.S Highway Maintenance Ltd | Construction | 2020 |
| B.B.Fatima Halal Meat & Fish Ltd | Wholesale & retail | 2025 |
| B.K.C Building & Roofing Limited | Construction | 2005 |
| B.L. Coomer Limited | Real estate | 1961 |
| B.Muss Build Ltd | Construction | 2025 |
| B2OLOGY Ltd | Wholesale & retail | 2023 |
| Baba Energy Ltd | Professional & scientific | 2024 |
| Baby More Limited | Wholesale & retail | 2011 |
| Bacanaks Limited | Hospitality | 2019 |
| Bacolet & Co Limited | Administrative & support | 2014 |
| Badala Data Services Ltd | Professional & scientific | 2024 |
| Bafta Investments Ltd | Hospitality | 2025 |
| Bafumze Ltd | Information & communication | 2023 |
| Bafumze Property Limited | Real estate | 2024 |
| Bains Construction(Uk) Limited | Construction | 2023 |
| Bala Ylli Construction Ltd | Construction | 2018 |
| Balaji Specialists Limited | Health & social care | 2012 |
| Balancing Health Limited | Other services | 2022 |
| Baldan Flooring Limited | Construction | 2025 |
| Balloons-On-Sea Ltd | Wholesale & retail | 2025 |
| Ballroom With Rocky Limited | Education | 2022 |
| Balrampur Hospital Foundation Balrampur UK | Health & social care | 2007 |
| Bamalex Limited | Professional & scientific | 2021 |
| Bamidelesoti Consult Ltd | Health & social care | 2022 |
| Bamotra Estates Ltd | Real estate | 2012 |
| Bamotra Ltd | Wholesale & retail | 2026 |
| Banana Nails Spa Ltd | Other services | 2026 |
| Banana Suites Ltd | Hospitality | 2024 |
| Bangkok Food Limited | Hospitality | 2023 |
| Bankymoore Ltd | Professional & scientific | 2008 |
| Banq Technology Limited | Information & communication | 2024 |
| Bantam Consultancy Ltd | Administrative & support | 2021 |
| Banulla Bespoke Ltd | Manufacturing | 2023 |
| Bar Care Consultancy Limited | Professional & scientific | 2026 |
| Bara Limited | Administrative & support | 2007 |
| Baran Bay Renovations Limited | Construction | 2025 |
| Barbara Agent Limited | Professional & scientific | 2026 |
| Bardon Electrical Services Limited | Construction | 1986 |
| Barihub Ltd | Administrative & support | 2025 |
| Barker Services London Ltd | Real estate | 2021 |
| Barkshire Hathaway Ltd | Real estate | 2015 |
| Barkshire Properties LLP | | 2018 |
| Barney Bears Nursery's Ltd | Real estate | 2003 |
| Barrels OFF Licence Limited | Wholesale & retail | 2010 |
| Barrels Properties Ltd | Real estate | 2017 |
| Barrels UK Care Ltd | Administrative & support | 2016 |
| Barrett`S Fitted Furniture Limited | Construction | 2009 |
| Barrkee Consulting Limited | Information & communication | 2007 |
| Barthena Management Ltd | Real estate | 2018 |
| Barthena Properties Ltd | Real estate | 2022 |
| Barwick Locksmiths and Maintenance Ltd | Construction | 2023 |
| Barwood Securities Limited | Construction | 1977 |
| BAS Accountancy Services Ltd | Professional & scientific | 2024 |
| Base Pharma Academy Limited | Education | 2025 |
| Basha Holdings Limited | Financial services | 2024 |
| Basildon Service Centre Ltd | Wholesale & retail | 2018 |
| Batali Ltd | Construction | 2018 |