| Alanda Properties Ltd | Norwich | 2021 |
| Alandale Building & Fit OUT Limited | Kent | 2006 |
| Alandale Holdings Limited | Beckenham | 1996 |
| Alandale Logistics Limited | Beckenham | 1996 |
| Alandale Plant & Scaffolding Limited | Beckenham | 2002 |
| Alandale Scaffolding Services Limited | Beckenham | 2021 |
| Alandernewie Ltd | Plymouth | 2015 |
| Alang Construction Ltd | London | 2025 |
| Alangate Ltd | Bradford | 2023 |
| Alani Joinery Limited | Heald Green | 2022 |
| Alankar Group Limited | Bedford | 2020 |
| Alanko Limited | Gillingham | 2017 |
| Alanna Properties Ltd | Leicester | 2021 |
| Alannah Construction Ltd | West Drayton | 2025 |
| Alannie Consulting Limited | New Cumnock | 2003 |
| Alano Consulting Limited | Bristol | 1995 |
| Alanor Services Ltd | Hull | 2017 |
| Alans Builging Limited | Croydon | 2025 |
| Alans Electrical Services Reading Ltd | Reading | 2017 |
| Alans Solutions Limited | Liverpool | 2025 |
| Alanson Consulting Limited | Rochford | 2000 |
| Alante Building Services Ltd | Birmingham | 2018 |
| Alantu Enterprise Ltd | London | 2022 |
| Alanya Ltd | Kent | 2017 |
| Alar Construction Ltd | Hatfield | 2019 |
| Alar Distribution Ltd | Ilford | 2020 |
| Alargan International Real Estate UK Limited | London | 2007 |
| Alario Ltd | London | 2023 |
| Alaris Developments Limited | London | 2016 |
| Alaris Properties Limited | Barnet | 2020 |
| Alarm and Communication Systems Limited | District 6 Washington | 1986 |
| Alarm and Electrical System Support Ltd | Bristol | 2017 |
| Alarm Communication Limited | London | 1984 |
| Alarm Guard Yorkshire Limited | London | 2026 |
| Alarm Installation Ltd | London | 2020 |
| Alarm Maintenance Cambridge Limited | Cambridge | 2020 |
| Alarm Repairs Rochdale Limited | Rochdale | 2013 |
| Alarm Smart Limited | Berwick-Upon-Tweed | 2019 |
| Alarm Solutions Ltd. | Stotfold | 2012 |
| Alarm Technologies (UK) Ltd | Hunwick Durham | 2012 |
| Alarm-Tech Installations Limited | Waterlooville | 2002 |
| Alarmco Fire & Electrical Ltd | Hamilton | 2018 |
| Alarmfix Ltd | Daventry | 2018 |
| Alarmix Limited | Ilford | 2026 |
| Alarms 4 Scaffolding Limited | Bushey | 2009 |
| Alarms of Cambridge Limited | Cambridge | 2020 |
| Alarmtec Limited | Exeter | 1977 |
| Alaro Energy Ltd | Billericay | 2026 |
| Alas Building Ltd | Crowborough | 2020 |
| Alas Construct Ltd | Peterborough | 2019 |
| Alasan Developments Limited | Wisbech | 2010 |
| Alasas Almateen Ltd | London | 2023 |
| Alasco Limited | Kent | 2017 |
| Alasdair a Morrison Ltd | Isle Of North Uist | 2008 |
| Alasdair I Campbell Limited | Isle Of Skye | 2008 |
| Alaska Consulting Limited | Cheltenham | 2023 |
| Alaska Developments Limited | Ipswich | 2016 |
| Alaska Ecological Contracting Ltd | Wareham | 1997 |
| Alaska Stone Ltd | London | 2019 |
| Alaskan (UK) Limited | Peterborough | 2003 |
| Alaskan Windows Ltd | Sutton | 2004 |
| Alast Developments Limited | Long Marston | 2016 |
| Alast Exteriors Limited | Leeds | 2006 |
| Alastair Bramwell Plumbing & Heating Limited | Wiltshire | 2001 |
| Alastair Dick Tarmac Limited | Glasgow | 2013 |
| Alastair Macdonald & SON Ltd | Glasgow | 2005 |
| Alastair Mchenry Construction Ltd | Ballycastle | 1999 |
| Alastair S Park Builders Limited | Gorebridge | 2020 |
| Alastair Thomas Decorating Ltd | Highams Park | 2016 |
| Alate Consulting Ltd | Swindon | 2013 |
| Alatus Construction Ltd | Milton Keynes | 2017 |
| Alatyr Construction Services Ltd | Kilmarnock | 2025 |
| Alauna Boiler Compliance Ltd. | Maryport | 2015 |
| Alauna Holdings Limited | Warwick | 2023 |
| Alauna Ltd | Stratford-Upon-Avon | 2023 |
| Alawaga Group for Management and Development and Agricultural Development a M G Ltd | Manchester | 2026 |
| Alaxas Constructions Ltd | Nottingham | 2025 |
| Alaxi Limited | Edinburgh | 2018 |
| Alaya Developers Ltd | Manchester | 2026 |
| Alaya Renovations Ltd | Eastleigh | 2026 |
| Alayna Construction Ltd | Ilford | 2022 |
| Alaz Building & Construction Ltd | London | 2024 |
| Alaz Electric and Maintenance Ltd | London | 2025 |
| Alazaroaie Ltd | Leighton Buzzard | 2025 |
| Alazov Ltd | Ilford | 2021 |
| ALB Affordable Contractors Ltd | Borehamwood | 2021 |
| ALB Applied Waterproofing Ltd | Salford | 2025 |
| ALB Basement & Construction Ltd | London | 2018 |
| ALB Black Country Properties Limited | Nottingham | 2016 |
| ALB Blackpool Limited | London | 2022 |
| ALB Blackwood Limited | London | 2021 |
| ALB Brickwork Limited | St. Albans | 2018 |
| ALB Build Ltd | Camberley | 2025 |
| ALB Building Landscaping Ltd | London | 2025 |
| ALB Building Ltd | London | 2021 |
| ALB Building Services Ltd | London | 2005 |
| ALB Burton Limited | Nottingham | 2021 |
| ALB Carpentry & Construction Ltd | Olney | 2024 |
| ALB Chesterfield Limited | Nottingham | 2024 |
| ALB Civils & Groundworks Ltd | Bridgwater | 2024 |