| A.B. Technical (East Anglia) Limited | King'S Lynn | 2019 |
| A.B. White Engineering Services Limited | Woolacombe | 2001 |
| A.B.B. Builders Ltd. | Edinburgh | 2019 |
| A.B.B. Developments Limited | Stanley | 2006 |
| A.B.C. (Floors) Limited | Sleaford | 2013 |
| A.B.C. Electrics Limited | Liverpool | 2011 |
| A.B.C. Finishing Systems Ltd | Pontypridd | 2020 |
| A.B.C. Productions Limited | Edinburgh | 1978 |
| A.B.C. Roofing Limited | Middlesex | 1998 |
| A.B.C. Services (Thatcham) Limited | Berkshire | 2003 |
| A.B.Ch Construction Ltd | London | 2023 |
| A.B.D. Builders Limited | Irlam | 2005 |
| A.B.F. Properties Limited | London | 1961 |
| A.B.G Construction UK Ltd | London | 2021 |
| A.B.G. Electrical & Mechanical Services Ltd. | Huntingdon | 2018 |
| A.B.H. Builders & SON Limited | Leigh | 2014 |
| A.B.I. Security Limited | Solihull | 2006 |
| A.B.Jenson Electrical Services Limited | Aylesbury | 2014 |
| A.B.K Construction & Design Ltd | Leeds | 2026 |
| A.B.L Building Limited | Nuneaton | 2006 |
| A.B.L. Developments Limited | Bolton | 1998 |
| A.B.L. Electrical Contractors Ltd. | Sunderland | 2012 |
| A.B.M.P. Ltd | Tipton | 2014 |
| A.B.P. Suffolk Developments Limited | Ipswich | 2007 |
| A.B.R. Roofing Services Limited | | 1996 |
| A.B.S Basement Systems Limited | Edgware | 2024 |
| A.B.S Contracts Limited | Witham | 2025 |
| A.B.S Design & Build Ltd | East Grinstead | 2022 |
| A.B.S Property Specialists Limited | Sheffield | 2015 |
| A.B.S Roofing Midlands Ltd | Birmingham | 2003 |
| A.B.S. (NW) Ltd | Prescot | 2025 |
| A.B.S. Facades Ltd | Stockton-On-Tees | 2018 |
| A.B.S. Property Care Limited | Edgware | 2014 |
| A.B.S./ Elbrow Limited | Bristol | 1993 |
| A.B.W.Heating Limited | Addlestone | 1970 |
| A.B.Y. Artisans Ltd | Northampton | 2026 |
| A.Barham Builders Ltd | Lincoln | 2018 |
| A.Baul Roofing Contractors Ltd | Pontypridd | 2020 |
| A.Bayes Services Ltd. | Isleworth | 2014 |
| A.Bell & Co,Limited | Northampton | 1905 |
| A.Bennett Properties Limited | Liverpool | 1962 |
| A.Bernie & Co.(Queensferry Auction)Limited | Hawarden | 1951 |
| A.Betteridge Ltd | Heanor | 2024 |
| A.Beynon Agri Envirocon Limited | Swansea | 2011 |
| A.Blake Construction Ltd | Brentwood | 2024 |
| A.Blick & SON Ltd. | Redditch | 1995 |
| A.Bmultifinishing Limited | Wolverhampton | 2025 |
| A.Bonaj Construction Ltd | Birmingham | 2026 |
| A.Bradshaw Steel Erectors Ltd | Poulton-Le-Fylde | 2026 |
| A.Branson Building & Construction Ltd | Hinckley | 2026 |
| A.Breck Electrical Ltd | Whitstable | 2019 |
| A.Buckler Haulage Limited | Cleveland | 1960 |
| A.Builder Limited | Bromsgrove | 2018 |
| A.Burslem & SON Limited | Tunbridge Wells | 1923 |
| A.C & Sons Limited | Cranleigh | 2005 |
| A.C Civils & Concrete Ltd | Galashiels | 2025 |
| A.C Ductwork Ltd | Solihull | 2018 |
| A.C Ductwork Services Ltd | London | 2011 |
| A.C Electrical Contractors Ltd | Chichester | 2006 |
| A.C Landscaping and Building Services Ltd | Grantham | 2025 |
| A.C Roads & Driveways Ltd | Galashiels | 2019 |
| A.C Solar Limited | North Watton At Stone | 2025 |
| A.C. Asbestos Ltd | Nottingham | 2026 |
| A.C. Beck & SON (Contracts) Limited | Wokingham | 1977 |
| A.C. Building Consultancy Ltd | Ruislip, | 2024 |
| A.C. Butler & SON Limited | Mapperley | 1963 |
| A.C. Connection Limited | Warwick | 2005 |
| A.C. Electrical (S.W.) Limited | St Agnes | 2015 |
| A.C. Electrical Solutions Limited | Redditch | 2012 |
| A.C. Electrics (Cleland) Ltd. | Motherwell | 2004 |
| A.C. Electrics Contracting Limited | Leominster | 2011 |
| A.C. Electrics Contractors Ltd | Kenilworth | 2018 |
| A.C. Engineering (Hope Valley) Limited | High Peak | 2007 |
| A.C. Enterprises (Crewkerne) Ltd | Crewkerne | 2007 |
| A.C. Environmental Services Limited | Norwich | 1986 |
| A.C. Fixes Limited | Cardiff | 2025 |
| A.C. Gutter Services Ltd | Lochgelly | 2023 |
| A.C. Hitchens Limited | Torquay | 2002 |
| A.C. Lessels Ltd. | Midlothian | 1998 |
| A.C. Lloyd (Asset Management) Limited | Warwick | 1998 |
| A.C. Lloyd Holdings Limited | Warwick | 1948 |
| A.C. Locks Ltd | Stourbridge | 2021 |
| A.C. Marriott Ltd. | Southport | 2008 |
| A.C. Mechanical Services Limited | Wotton Under Edge | 1972 |
| A.C. Mervyn Day Limited | Cirencester | 2003 |
| A.C. Metters Decorating Contractors Limited | Clyst St Mary | 2011 |
| A.C. Mitton Limited | Preston | 2001 |
| A.C. Neal Limited | Poole | 2003 |
| A.C. Nurden Limited | Malmesbury | 1986 |
| A.C. Pipework Ltd | Merseyside | 2004 |
| A.C. Powell Plumbing Services Limited | Margate | 2024 |
| A.C. Puddle & Co. Limited | Gwent | 1974 |
| A.C. Services (Kent) Limited | Kent | 2017 |
| A.C. Solutions (G.B) Limited | Banbury | 2004 |
| A.C. UK Services Ltd | Pontefract | 2024 |
| A.C. Vaale Ltd | Northolt | 2021 |
| A.C. Ventilation Limited | Rochdale | 1995 |
| A.C. Wallbridge and Company Limited | Salisbury | 1978 |
| A.C. Wilgar Limited | Orpington | 1996 |
| A.C.A. Scaffolding Limited | Hassocks | 1998 |