| A Mitchell Interiors Limited | Essex | 2007 |
| A Modern Design Limited | Staplefield | 2019 |
| A Modern Energy Ltd | Porthcawl | 2014 |
| A Moffatt Stoneworks Limited | Weston-Super-Mare | 2014 |
| A Moloney Construction Limited | London | 2007 |
| A Moor Electrical Limited | Southampton | 2013 |
| A Moorekite Management Limited | Maidstone | 2014 |
| A Morris Contractors Limited | Bristol | 2023 |
| A Morris Diamond Drilling Limited | Basingstoke | 2006 |
| A Morris Roofing Limited | Aberdeen | 2017 |
| A Morris Traffic Ltd | Doncaster | 2024 |
| A Moys Plumbing Services Ltd | North Walsham | 2000 |
| A Murphy Ltd | Liverpool | 2025 |
| A Musleh Ltd | Birmingham | 2022 |
| A N & G Property Limited | Brighouse | 2013 |
| A N & SON Limited | Kinross | 2008 |
| A N a Builders Limited | Wolverhampton | 2016 |
| A N a Electrical Limited | Hyde | 2005 |
| A N a Plumbing & Heating Ltd | Priorslee | 2014 |
| A N Builders Ltd | Croydon | 2024 |
| A N Building Services Limited | London | 2012 |
| A N Carpentry & Construction Limited | Worthing | 2022 |
| A N Carpentry Contracting Ltd | St. Neots | 2018 |
| A N Carpentry Limited | Marlborough | 2019 |
| A N City Plumbing and Heating Limited | Stockport | 2021 |
| A N Cleveland Limited | Sudbury | 2015 |
| A N Construction Services Ltd | Bridlington | 2018 |
| A N Construction Solution Limited | Wembley | 2008 |
| A N D Building Ltd | London | 2016 |
| A N D Electrical Limited | Leicester | 2005 |
| A N D Home Solutions Ltd | London | 2016 |
| A N Design Group Ltd | London | 2021 |
| A N E Electrical Ltd | Glenrothes | 2023 |
| A N Electrical Limited | Sidcup | 2003 |
| A N F Construction Limited | Stevenage | 2015 |
| A N Game Building Contractors Ltd | Ware | 2013 |
| A N George Groundworks Limited | Hatfield | 2017 |
| A N Heating Limited | Trowbridge | 2008 |
| A N Heating Services Limited | Airdrie | 2022 |
| A N Hill & SON Limited | Black Notley | 2020 |
| A N Joinery Limited | Wolverhampton | 2023 |
| A N K Developer Ltd | Barnsley | 2017 |
| A N M Builders Limited | London | 2015 |
| A N Metering Ltd | Edinburgh | 2025 |
| A N Orchard Limited | Herne Bay | 2001 |
| A N Plumbing & Heating Limited | Bedford | 2016 |
| A N Plumbing Limited | Nantwich | 2022 |
| A N Property Solutions Limited | Manchester | 2018 |
| A N R Specialists Limited | Exeter | 2017 |
| A N Scarratt Plumbing & Central Heating Ltd | Northants | 2005 |
| A N Smith Roofing Co Limited | Rochford | 2010 |
| A N Tarmacadam Ltd | Torquay | 2022 |
| A N Tiling Limited | St. Albans | 2019 |
| A N White (Building Contractors) Limited | Wisbech | 2003 |
| A Naqui NDT & Rope Access Limited | Stockton On Tees | 2026 |
| A Nawab Ltd | Ilford | 2024 |
| A Nelson Brickwork Ltd | South Shields | 2022 |
| A Nelson Building Ltd | Ballynahinch | 2022 |
| A Nelson Rail Services Ltd | Stockton-On-Tees | 2015 |
| A New Dawn Development Limited | Colchester | 2025 |
| A New View Cleaners Ltd | Haywards Heath | 2020 |
| A Newer Hope Ltd | Dagenham | 2024 |
| A Newson Engineering Ltd | Aylesford | 2014 |
| A Newton Building Services Limited | Nottingham | 2000 |
| A Newton Civil Engineering Limited | Wigan | 2018 |
| A Nicewicz Construction UK Ltd | London | 2010 |
| A Nicholls Contracts Ltd | Halesowen | 2025 |
| A Nicholls Services Ltd | Birmingham | 2024 |
| A Noon Construction Ltd | Farnborough | 2024 |
| A Norris Limited | Scunthorpe | 2020 |
| A North Thatching Ltd | Newton Abbot | 2026 |
| A Norton Building Ltd | Cardiff | 2021 |
| A O Boateng Ltd | Enfield | 2021 |
| A O Building Ltd | Southampton | 2024 |
| A O H Electrical Ltd | London | 2018 |
| A O Kitchens Ltd | Whitstable | 2018 |
| A O R Electrical Ltd | Broadstairs | 2024 |
| A O Sealants Ltd | Frodsham | 2022 |
| A O Site Services Ltd | Barnsley | 2018 |
| A O'Brien Building Services Limited | Birmingham | 2005 |
| A O'Brien Construction & Landscaping Ltd | Wigan | 2017 |
| A O'Callaghan Contracts Ltd | Newry | 2022 |
| A O'Connor Building Services Ltd | Margate | 2020 |
| A O'Hara Carpentry Services Ltd | Cradley Heath | 2002 |
| A O'Hare Joinery & Building Ltd | Liverpool | 2017 |
| A O'Sullivan Brickwork Ltd | Solihull | 2022 |
| A Oakenfull Groundworks Ltd | Sudbury | 2003 |
| A Oaten (Groundworks) Limited | Wellington | 2015 |
| A Ogden Building & Ground Work Ltd | Bury | 2019 |
| A OK Installations Limited | Magherafelt | 2005 |
| A Oliver & Sons Joiners Ltd | Hawick | 2017 |
| A Oliver Plumbing and Heating Limited | Stalybridge | 2024 |
| A One Brar Flooring Ltd | Wellingborough | 2023 |
| A One Builders & Merchants Ltd | Berkshire | 2001 |
| A One Construction Bridgend Limited | Bridgend | 2012 |
| A One Integrated Highway Services Limited | Birmingham | 1999 |
| A One Window Systems Ltd | Swansea | 2015 |
| A One. Heating & Plumbing Services Ltd | Hinckley | 2018 |
| A Ones Builders Limited | Birmingham | 2025 |
| A ONG Limited | London | 2012 |