| Ardmore Properties Limited | Real estate | 2003 |
| Areahurst Limited | Wholesale & retail | 1986 |
| Arena Hair & Beauty Limited | Other services | 2004 |
| Argex Limited | Manufacturing | 1994 |
| Arif Nawab Limited | Real estate | 2006 |
| Armstrong Family Services Limited | Wholesale & retail | 2001 |
| Arne Trade Company Limited | Manufacturing | 2023 |
| AROMATIC89 Ltd | Manufacturing | 2025 |
| Aroonz Trading Limited | Wholesale & retail | 2018 |
| Art Industrial Limited | Construction | 2003 |
| Art of Network Limited | Administrative & support | 2004 |
| Arthur Ashmore (Tailors) Limited | Manufacturing | 1978 |
| Arthur Morgan & SON Limited | Construction | 2001 |
| Arthurmo Electrical Engineers Limited | Manufacturing | 2004 |
| Arundales (Knowle) Limited | Professional & scientific | 2003 |
| Asal Enterprise Limited | Other services | 2024 |
| Ascon Holdings Limited | Professional & scientific | 2001 |
| Ascon Industrial Roofing Limited | Construction | 1972 |
| Ashley House (Dudley) Management Company Limited | Real estate | 1990 |
| Ashrose Hotels Limited | Hospitality | 2001 |
| Ashton Engineering Company Limited | Wholesale & retail | 1924 |
| Ashtons Business Services Limited | Professional & scientific | 2001 |
| Ashwood Marina Limited | Administrative & support | 1965 |
| Ashwood Nurseries Limited | Wholesale & retail | 1995 |
| Assa Abloy (UK) Pension Trustees Limited | Professional & scientific | 2000 |
| Assa Abloy Limited | Manufacturing | 1987 |
| Assp Holdings Limited | Financial services | 2004 |
| Aston Microscopy & Engineering Limited | Professional & scientific | 2006 |
| AT Leisure 2009 Limited | Construction | 2009 |
| ATC Park Homes and Lodges Ltd | Construction | 2026 |
| Atlas Ball and Bearing Co. Limited | Wholesale & retail | 1977 |
| Atlas Engineering Services (Midlands) Ltd | Manufacturing | 2003 |
| Atlas for General Services Co., Ltd | Wholesale & retail | 2024 |
| Atotech UK Limited | Wholesale & retail | 1977 |
| ATP Associates Limited | Professional & scientific | 2007 |
| Atul Khanna Limited | Real estate | 2005 |
| Aubrey Aerospace Technology Co., Ltd | Manufacturing | 2022 |
| Aumovio Trading UK Limited | Manufacturing | 1969 |
| Aurol Technologies Limited | Health & social care | 2006 |
| Austcliffe Park Limited | Hospitality | 2004 |
| Auto Claims (UK) Limited | Administrative & support | 2002 |
| Auto Diagnosis Centre Limited | Wholesale & retail | 2004 |
| Auto Surefit Limited | Wholesale & retail | 2000 |
| Autogard (U.K.) Limited | Manufacturing | 1982 |
| Automatic System Design Limited | Information & communication | 2002 |
| Automotive Data Solutions Limited | Information & communication | 2004 |
| Autoservice Muschalle Limited | Administrative & support | 2005 |
| Avalon Creative Ltd | Information & communication | 2007 |
| Avalon Refrigeration Limited | Transport & logistics | 1997 |
| Avandene Developments Limited | Construction | 2007 |
| Avanti Engineering Services Limited | Manufacturing | 1996 |
| Avcon Aviation Consultants Limited | Transport & logistics | 1994 |
| Avery Weigh-Tronix Limited | Financial services | 1957 |
| Avon Drive Management Company Limited | Households | 1999 |
| AWK - Trade Limited | Administrative & support | 2005 |
| Ayaan and Emaan Limited | Health & social care | 2013 |
| Ayurvedic & Homoeopathic Clinic Limited | Health & social care | 2003 |
| Azemco Limited | Professional & scientific | 1978 |
| B C S Associates Limited | Health & social care | 1998 |
| B E Wedge Limited | Manufacturing | 2003 |
| B J Stevens Transport Limited | Information & communication | 2001 |
| B M Electrical Wholesalers Limited | Wholesale & retail | 2002 |
| B M Homes Limited | Professional & scientific | 2005 |
| B M P Properties Limited | Real estate | 2000 |
| B S a Couriers Limited | Transport & logistics | 2004 |
| B S S Electrical Contractors Limited | Construction | 1988 |
| B&B Carpet Ltd | Wholesale & retail | 2023 |
| B. & G. Transport (Dudley) Limited | Transport & logistics | 1979 |
| B. & S. Threaded Products Limited | Manufacturing | 1968 |
| B. E. Barker Limited | Construction | 1984 |
| B. M. I. Foundry Services Limited | Wholesale & retail | 1983 |
| B.E. Wedge Holdings Limited | Manufacturing | 1938 |
| B.E.C (Midlands) Limited | Administrative & support | 2006 |
| B.G.Bullas Limited | Manufacturing | 1963 |
| B.I.T Consultancy Limited | Information & communication | 2006 |
| B.M.I. Engineering Limited | Manufacturing | 1975 |
| B.O.E. (Bowmen of England) Limited | Manufacturing | 1995 |
| B.R.M. Builders Ltd | Construction | 2006 |
| B4CKY Limited | Professional & scientific | 2000 |
| B92 Architectural Design Limited | Professional & scientific | 2007 |
| Baah Limited | Real estate | 2005 |
| Badial Retail Limited | Wholesale & retail | 2003 |
| BAH Solutions Limited | Professional & scientific | 2007 |
| Baig Properties (UK) Ltd | Real estate | 2002 |
| Bains and Daughters Limited | Wholesale & retail | 2006 |
| Baisai International Limited | Wholesale & retail | 2021 |
| Banbury Alarms Ltd | Other services | 1997 |
| Banga & Gill Properties Limited | Real estate | 2002 |
| Banner Roofing Ltd | Construction | 2007 |
| Banners Lane Engineering Company Limited | Manufacturing | 1967 |
| Bannocks (Tigre) Marble Company Limited | Manufacturing | 1946 |
| Bansals Limited | Wholesale & retail | 1983 |
| Barber & Nicholls,Limited | Professional & scientific | 1932 |
| Barford Old Rectory Management Company Limited | Real estate | 1973 |
| Bargain Vans Limited | Wholesale & retail | 2001 |
| Barkley Holdings Limited | Professional & scientific | 2001 |
| Barnett Ravenscroft Financial Services Limited | Financial services | 2000 |
| Barry Thompson & Co Limited | Wholesale & retail | 2002 |
| Basset Trading Limited | Transport & logistics | 1990 |
| Bateman Roofing Services Limited | Construction | 2007 |