| A.O.T Engineering Holdings Ltd | Fakenham | 2018 |
| A.O.T Engineering Ltd | Fakenham | 2012 |
| A.Of.E Ltd | Edinburgh | 2013 |
| A.One Feed Supplements Limited | Thirsk | 1975 |
| A.P. (East Anglia) Limited | Thetford | 1997 |
| A.P. Alarms Ltd. | Yateley | 1990 |
| A.P. Diesels Limited | Egham | 1978 |
| A.P. Diving Limited | Helston | 1988 |
| A.P. Engineering (Portsmouth) Limited | Mildenhall | 1963 |
| A.P.A. Design Consultants Limited | | 1994 |
| A.P.C. Electrical Limited | Cleckheaton | 2002 |
| A.P.C. Fashions Limited | Hucknall | 1995 |
| A.P.C. Panels Ltd. | Barry | 1993 |
| A.P.C. Schoolwear Limited | Hucknall | 1995 |
| A.P.D. Fabrications Ltd | Darlaston | 2020 |
| A.P.D. Truck Mixer Repairs Ltd | Darlaston | 2010 |
| A.P.E (Yorks) Limited | Sheffield | 2009 |
| A.P.H Carpentry Ltd | Peterborough | 2025 |
| A.P.H. Industries Limited | Fairfield | 1984 |
| A.P.H. Windows Ltd. | Shropshire | 2002 |
| A.P.K Installation Services Ltd. | Tipton | 2019 |
| A.P.S. Engineering Limited | Buckinghamshire | 1984 |
| A.P.T. Marine Engineering Limited | Grimsby | 1987 |
| A.P.T. Patterns Limited | Chesterfield | 2005 |
| A.Pamphilon & Sons (Walthamstow) Limited | London | 1961 |
| A.Perry Ltd | West Midlands | 1940 |
| A.Pinder Limited | Sheffield | 1938 |
| A.Poole & SON Limited | Worcs | 1950 |
| A.Prints Limited | London | 2022 |
| A.R. Adams & Sons (Printers) Limited | Dover | 1975 |
| A.R. Ball Engineering Limited | Ryde | 1973 |
| A.R. Dixon Display Limited | Northampton | 1978 |
| A.R. Hurst (Lithaprint) Limited | Bolton | 1978 |
| A.R. Manley & SON Limited | Nr Shrewsbury | 2020 |
| A.R. Mobile Welding Fabricating Ltd | Wednesbury | 2026 |
| A.R. Paper Converters Ltd | Essex | 1987 |
| A.R. Thorne Memorials Limited | Dawlish | 2003 |
| A.R. Welding Services Limited | Birmingham | 2020 |
| A.R. Wentworth (Sheffield) Limited | Sheffield | 1982 |
| A.R. Wholesale Limited | Middlesbrough | 2020 |
| A.R. Willis Catering Trailers Ltd. | Royston | 2009 |
| A.R.B Blade Services Ltd | Whitehaven | 2023 |
| A.R.B. Builders & Joiners Limited | Bolton | 2003 |
| A.R.C Resources Ltd | Aberdeen | 2024 |
| A.R.E. Medical Ltd | Beckenham | 2023 |
| A.R.Facer Limited | Leeds | 1938 |
| A.R.G. Limited | Co Armagh | 1997 |
| A.R.H Aircraft Maintenance Ltd | Cambridge | 2019 |
| A.R.Jolly Limited | Richmond | 1954 |
| A.R.L. Design and Welding Limited | Burntwood | 2001 |
| A.R.L. Equipment Ltd | Saxmundham | 2012 |
| A.R.M Logic Solutions Limited | Ipswich | 2024 |
| A.R.M. (Productions) Limited | Staffs | 1964 |
| A.R.M. (Wales) Limited | Cardiff | 2006 |
| A.R.M. Maritime Services Limited | Norwich | 2016 |
| A.R.M.S. Plant Limited | Taunton | 2009 |
| A.R.O Building and Maintenance Ltd | Liverpool | 2025 |
| A.R.T. Engineering (N.I.) Ltd | Ballymena | 2015 |
| A.R.T. Plant Limited | Leeds | 1968 |
| A.R.T.(G.B.) Limited | Preston | 1990 |
| A.R.T.Property Services Dorset Ltd | Dorchester | 2018 |
| A.R.V. Agricultural Engineering Limited | Sherborne | 2003 |
| A.Russell Tech Services Ltd | Withernsea | 2025 |
| A.S Apothecary Limited | Stratford-Upon-Avon | 2015 |
| A.S Highways Safety Limited | Earl Shilton | 2026 |
| A.S Renewable Services Ltd | Gateshead | 2023 |
| A.S Safety and Technology Limited | Earl Shilton | 2024 |
| A.S. Agricultural Services Limited | Swadlincote | 2003 |
| A.S. Audhali Farm Gate Fresh Poultry Limited | Warwick | 1981 |
| A.S. Boiler Building Services Ltd | Brighton | 2015 |
| A.S. Building Services Ltd | | 2004 |
| A.S. Ductwork Limited | Uxbridge | 2000 |
| A.S. Handover Limited | Welwyn Garden City | 1949 |
| A.S. Marine Power Solutions Ltd | London | 2016 |
| A.S. Mcgill Limited | Croydon | 1977 |
| A.S. Newbould Limited | Wirral | 1972 |
| A.S. Pressure Engineering Limited | Basingstoke | 2001 |
| A.S. Property and Construction Limited | Hamilton | 2021 |
| A.S. Rubber & Plastics Limited | West Midlands | 1995 |
| A.S. Scientific Products Limited | Abingdon | 1976 |
| A.S. Sheetmetal Limited | Doncaster | 2002 |
| A.S.A. Trading (UK) Ltd | Nottingham | 2010 |
| A.S.A.P Steel Fabrications Ltd | Letchworth Garden City | 2019 |
| A.S.B. (Engineers) Limited | Glasgow | 1988 |
| A.S.C. CNC Limited | Nuneaton | 2002 |
| A.S.C. Wiring Solutions Ltd | Bressingham | 2007 |
| A.S.C.(Ayrshire SAW Centre) Ltd | Irvine | 2020 |
| A.S.G. Fabrications Limited | Batley | 2002 |
| A.S.H. Plastics (Wolverhampton) Limited | Wolverhampton | 1982 |
| A.S.H. Timberworks Ltd | New Romney | 2003 |
| A.S.H.S. Limited | London | 1996 |
| A.S.J. Manufacturing Limited | Wibsey | 1984 |
| A.S.K Plumbing and Heating Limited | Haywards Heath | 2010 |
| A.S.K Projects Ltd | Bedford | 2018 |
| A.S.K. Rewinds Ltd. | Accrington | 1998 |
| A.S.L.R. Fabrication Services Ltd. | Stone | 1992 |
| A.S.Lloyd & SON Limited | Llandow Cowbridge | 1967 |
| A.S.M Welders Ltd | Barry | 2018 |
| A.S.M. Fabrications Limited | Leeds | 2004 |
| A.S.N Driving Limited | London | 2014 |