| Aldenham Country Park Trust Limited | Borehamwood | 2011 |
| Aldenham Property Limited | Watford | 2002 |
| Alder Arts Ltd | Oxford | 2025 |
| Alder Asset Management Limited | London | 1977 |
| Alder Hills Barber Ltd | Poole | 2026 |
| Alder Investment Management Limited | London | 1987 |
| Alder Nominees Limited | London | 2012 |
| Alder Rose Mortgage Services Limited | Runcorn | 2018 |
| Alder Services Ltd | Worcester | 2015 |
| Alder Vale Trading Ltd | London | 2026 |
| Alderbank Residents Association Limited | Altrincham | 2026 |
| Alderborough Limited | Northallerton | 1994 |
| Aldercombe Lane Limited | Caterham | 1983 |
| Aldergrove House of Prayer | Crumlin | 2005 |
| Alderholt Chapel | Fordingbridge | 2022 |
| Alderley Capital (AMC) Limited | London | 2024 |
| Alderley Edge Wellness Clinic Ltd | Alderley Edge | 2021 |
| Alderley Farm Supplies Ltd | London | 2016 |
| Alderley Logs Ltd | Macclesfield | 2019 |
| Aldermans Close (Dixons Hill Road) Management Limited | Hatfield | 1970 |
| Aldersgate Limited | London | 2007 |
| Aldershot Barbers Club Ltd | Aldershot | 2020 |
| Aldershot Hair & Beauty Ltd | Aldershot | 2022 |
| Aldershot Masonic Properties Limited | Farnborough | 1961 |
| Aldershot Mens Grooming Ltd | Aldershot | 2019 |
| Aldershot Valeting Centre Ltd | Hampshire | 2018 |
| Alderson Beauty (Yorkshire) Ltd | Liversedge | 2024 |
| Alderson House (Warwick) Limited | Warwick | 1960 |
| Aldertec Ltd | Oxford | 2025 |
| Alderwest Limited | London | 1993 |
| Alderwood Ecology Limited | Kettering | 2026 |
| Alderwood Services Ltd | Liverpool | 2016 |
| Aldford Apparel Limited | Chester | 2014 |
| Aldgate Connect BID Limited | London | 2014 |
| Aldgate Electrical & Building Maintenance Ltd | London | 2009 |
| Aldgate Home Limited | London | 2012 |
| Aldgate International Limited | Manchester | 2023 |
| Aldgate Systems Limited | London | 2025 |
| Aldice Limited | London | 2012 |
| Aldingbourne Care Limited | Mitcham | 2015 |
| Aldington Evangelical Mission | Ashford | 2018 |
| Aldireco Group IBC Limited | Hythe | 2024 |
| Aldl Limited | Leicester | 2025 |
| Aldo Barbers Ltd | London | 2021 |
| Aldo Kane Ltd | London | 2025 |
| Aldo's Barbershop Ltd | Bristol | 2018 |
| Aldos Barber Ltd | London | 2021 |
| Aldotiler Limited | Northampton | 2017 |
| Aldridge Baber Ltd | Walsall | 2023 |
| ALE & Beer Supplies Ltd | | 2001 |
| ALE Canine Solutions Limited | Basingstoke | 2020 |
| ALE Water Valley Limited | Melrose | 2015 |
| Aleaf Windows UK Limited | Edgware | 2015 |
| Aleah J Hair Limited | Derby | 2025 |
| Alec Butcher Funeral Directors Limited | Witham | 2014 |
| Alec Industrial Solutions Limited | London | 2018 |
| Aledex Limited | Stoke-On-Trent | 2003 |
| Aledo Homes (UK) Limited | Littleport | 2018 |
| Aledo K9 Ltd | Tunbridge Wells | 2022 |
| Aleekto Ltd | London | 2023 |
| Aleem Global Limited | Bonnyrigg | 2024 |
| Aleen & Larin Ltd | Edinburgh | 2023 |
| Aleen Beauty Ltd | London | 2019 |
| Aleen Hairstyle Ltd | Glasgow | 2025 |
| Alees Aesthetics Limited | Surrey, Dorking | 2024 |
| Alegna Consultancy Ltd | London | 2016 |
| Alegra Associates Limited | Nottinghamshire | 2004 |
| Alegro Ltd | Ottery St. Mary | 2018 |
| Aleisaa Ltd | Harrow | 2023 |
| Alejandra DU SOL Limited | London | 2021 |
| Alejandra London Aesthetics Limited | Croydon | 2015 |
| Alejandro Ororbia Limited | Bolton | 2024 |
| Aleks Food Limited | Stockport | 2018 |
| Aleks Gilmerton Ltd | Edinburgh | 2024 |
| Aleks Jewellers Limited | Norwich | 2010 |
| ALEKS26 Limited | Llandudno Junction | 2016 |
| Aleksa's Beauty Ltd | Croydon | 2015 |
| Aleksandar Budic Limited | Lee-On-The-Solent | 2011 |
| Aleksandra 11 Ltd | London | 2011 |
| Aleksandra Rozanska Ltd | Folkestone | 2023 |
| Aleksandra Zych Ltd. | Ipswich | 2013 |
| Alektrya Ltd | Alsager | 2023 |
| Alelyan Ltd | London | 2025 |
| Alema Hair & Beauty Ltd | Wigan | 2013 |
| Alemane Ltd | London | 2025 |
| Alemave Ltd | London | 2024 |
| Alen Barbers Ltd | Leamington Spa | 2020 |
| Alen Global UK Limited | Staines-Upon-Thames | 2016 |
| Alen's Classic Barbers Ltd | Sheffield | 2026 |
| Alenci Haire Limited | London | 2025 |
| Alenco Group Ltd | London | 2022 |
| Alens Barber Leeds Ltd | Leeds | 2024 |
| Alens Barber Ltd | Wetherby | 2018 |
| Alens Nice Barber Ltd | Normanton | 2023 |
| Alenth Ltd | London | 2020 |
| Aleo Wellness Studio Limited | Warrington | 2025 |
| Alerah Cosmetics Ltd | London | 2020 |
| Alere Pharma Consulting Limited | Harrogate | 2021 |
| Alert 2020 Services Limited | Bexhill-On-Sea | 2011 |
| Alert Alarms Limited | Stourbridge | 2014 |