| A. C. Paintech Ltd | Mexborough | 2007 |
| A. C. Webb Facility Services Limited | Bury St. Edmunds | 2016 |
| A. Charles Limited | Corby | 2014 |
| A. Clarke Monumental Limited | Colchester | 2017 |
| A. Creed Engineering Ltd | Cambridge | 2025 |
| A. Diamond & SON (Timber) Limited | Coleraine | 1971 |
| A. E. & N. Ashton & Company Limited | Ely | 1955 |
| A. E. L. Flexaulic Limited | Liverpool | 1985 |
| A. E. Mccandless & Co. Limited | Co Londonderry | 1939 |
| A. Elliot (Fine Fabrics) Limited | Selkirk | 1965 |
| A. F. Jones Stonemasons Limited | Reading | 2009 |
| A. F. Ollies Engineering Ltd | Cheadle | 2015 |
| A. Farlow (Engineering) Ltd | | 2002 |
| A. Franklin & SON Limited | Northampton | 2022 |
| A. G. Bracey Limited | Pucklechurch | 1971 |
| A. G. Precision (Huntingdon) Limited | London | 1973 |
| A. G. V. F. Co. (Bristol) Limited | | 1978 |
| A. Gilligan (Coatings) Ltd | West Midlands | 2003 |
| A. Green Engineering (Lincoln) Limited | Lincoln | 1982 |
| A. H. Greaves Upholstery Limited | Brecon | 2002 |
| A. Harris Contracts Limited | Manchester | 2008 |
| A. Hartnell Marine Electrical Ltd | Bournemouth | 2015 |
| A. Holman Electrical Limited | Spalding | 2013 |
| A. I Appliance Care Ltd | Brockley | 2026 |
| A. I. G. Engineering Limited | Cheadle | 1981 |
| A. J. & L. Taylor UK Ltd | Bury | 2006 |
| A. J. Charlton & Sons Limited | Nr Frome | 1976 |
| A. J. English Ltd | Coventry | 2014 |
| A. J. F. Scott Limited | Stonehouse | 2003 |
| A. J. Fabrications Limited | Cranleigh | 2001 |
| A. J. Joinery Limited | Bury St. Edmunds | 1999 |
| A. J. Laminated Beams Limited | Bury St. Edmunds | 2001 |
| A. J. Mills Master Masons Limited | Leicester | 2003 |
| A. J. Orpin Carpentry Ltd | Chinnor | 2021 |
| A. Jarmson (Shetland) Ltd. | Lerwick | 2004 |
| A. Jones Joinery Limited | London | 2023 |
| A. K. Muller (UK) Limited | London | 1993 |
| A. Kelway Ltd | Chatteris | 2008 |
| A. Kenny & Sons Limited | Manchester | 2003 |
| A. Lafont Limited | Whitefield | 2021 |
| A. Lewis & Sons Limited | Birmingham | 1948 |
| A. Lewis and Sons (Willenhall) Limited | West Midlands | 1947 |
| A. M. C. (U.K.) Fasteners Limited | Northampton | 1977 |
| A. Markham & Sons Limited | Leigh On Sea | 1972 |
| A. Mistry Limited | Loughborough | 1994 |
| A. Mitchell Carpentry Limited | Radstock | 2016 |
| A. Morris & Sons (Dunsford) Limited | Nr Penryn | 1981 |
| A. Murray's Construction Ltd | Burnley | 2024 |
| A. O. Quinn Ltd | London | 2024 |
| A. Ostell & Co. Limited | Newcastle Upon Tyne | 1998 |
| A. P. Burt & Sons Limited | Bolton | 1933 |
| A. P. Metalising Limited | Stoke-On-Trent | 1994 |
| A. Pacak Design Ltd | London | 2004 |
| A. Parsons & Co (Liverpool) Limited | Merseyside | 1967 |
| A. Pickles Engineering Limited | Leeds | 2002 |
| A. Pollick Limited | Southport | 1934 |
| A. Proctor Construction Limited | Blairgowrie | 1997 |
| A. Q. (Central) Limited | West Midlands | 1997 |
| A. R. Archer Ltd | Worcester | 2002 |
| A. R. Baptie Limited | Ashford | 2002 |
| A. R. Rudge Limited | Kingswinford | 1960 |
| A. Riva and SON Shipwrights Limited | Burnham-On-Crouch | 2003 |
| A. Robinson Electrical Limited | Frinton-On-Sea | 2007 |
| A. S. B. (Railway Network) International Limited | Lower Earley | 1992 |
| A. S. Fabrication Ltd | Wellbank | 2010 |
| A. Schulman Gainsborough Ltd | Gainsborough | 1996 |
| A. Schulman Inc. Limited | Newport | 1952 |
| A. Schulman Thermoplastic Compounds Limited | Warrington | 1971 |
| A. Shotton Limited | Huddersfield | 2006 |
| A. Simmons Carpentry Ltd. | Hove | 2019 |
| A. Stanley Joiners Limited | Wakefield | 2005 |
| A. T. Graphics Limited | Orton Southgate | 1986 |
| A. T. Print Services Limited | Doncaster | 2003 |
| A. T. Sheds & Fencing Limited | Kingswinford | 2009 |
| A. Targett & Co Ltd | Bedford | 2023 |
| A. Taylor and Sons Limited | Leicester | 2000 |
| A. W. Bent Limited | Bude | 1946 |
| A. W. Stokes & SON (Drums) Limited | West Bromwich | 1965 |
| A. Weld Limited | Neath | 1991 |
| A. Williams Engineering Limited | Burscough | 1976 |
| A. Wise Signs Limited | High Wycombe | 2007 |
| A. Wright & SON Limited | | 1947 |
| A.& E.Squire Limited | Willenhall | 1960 |
| A.& F.Howland(Wycombe)Limited | Buckinghamshire | 1927 |
| A.& H.Formes Limited | Accrington | 1972 |
| A.& J.Scott Limited | Alnwick | 1972 |
| A.1. Finance Limited | Ballymena | 1983 |
| A.1. Ropes & Rigging Limited | Addlestone | 1990 |
| A.A. Brown Engineering Ltd | Leicestershire | 1961 |
| A.A. Coombes Limited | Bembridge | 2014 |
| A.A. Henton & SON (Steel Fabrications) Limited | Twycross,Atherstone, | 1979 |
| A.A. Packaging Limited | Walmer Bridge | 1983 |
| A.A.C.R & Ltd | London | 2023 |
| A.A.Carpentry Ltd | Wigan | 2025 |
| A.A.I. Alarms Limited | Stirling Way, Borehamwood | 1988 |
| A.A.J. Engineering Limited | Tamworth | 1986 |
| A.A.L.S Global Solutions & Global Assistive Robotics Ltd | Bedford | 2026 |
| A.A.P.Carpentry Ltd | Wigan | 2025 |
| A.A.S. Electrics Ltd | Barnet | 2020 |
| A.A.S.C. (Antioxidants Analysts Suppliers & Consultants) Limited | Lyndhurst | 1997 |