| Allied Dunbar Financial Services Limited | Swindon | 1975 |
| Allied Dunbar Provident PLC | Swindon | 1964 |
| Allied Export Ltd | Warrington | 2011 |
| Allied Hotels Limited | Torquay | 1937 |
| Allied Logistics and Warehousing Limited | Salford | 2021 |
| Allied Managed Services Limited | Manchester | 2014 |
| Allied Projects Industry Limited | Cambridge | 2011 |
| Allied Sheen Co., Ltd | London | 2015 |
| Allied Supported Housing Ltd | Coventry | 2016 |
| Allied Trades Ltd | Manchester | 2025 |
| Allied Training Services Ltd | Aberdeen | 2019 |
| Allied Turbine Limited | London | 2003 |
| Allimpex Invest Limited | London | 2025 |
| Allison 1956 Limited | Cambridge | 2013 |
| Allison Electronics Co., Ltd. | Beckenham | 2015 |
| Allison Fluid Power Limited | Warrington | 1998 |
| Allison Hilary Bullock Ltd | London | 2023 |
| Allison Holding Investment Limited | London | 2022 |
| Allison Homes (Pinchbeck) Limited | Peterborough | 2015 |
| Allison Homes Eastern Limited | Solihull | 2001 |
| Alliston Villa Management Limited | Wisbech | 2015 |
| Allium & Brassica Agronomy Limited | Lincoln | 2005 |
| Allman Management Limited | Chester | 1991 |
| Allmark Limited | Rhyl | 2000 |
| Allmed Medical Nominee NO. 1 Limited | London | 2012 |
| Allmond Bell Ltd. | Radlett | 2013 |
| Allmotion Hydraulics Group Ltd | Newhaven | 2022 |
| Allmotive Limited | Cardiff | 2007 |
| Allnet Limited | Hatfield | 1965 |
| Alloa Construction Services Limited | Alloa | 2024 |
| Alloa Glazing Ltd | Grangemouth | 2025 |
| Allodium Limited | Woking | 2006 |
| Allora Services Ltd | Egham | 2021 |
| Alloway Holdings Limited | London | 2020 |
| Alloway Properties Limited | London | 2020 |
| Alloway Timber (Southern) Limited | London | 1971 |
| Alloway Timber Limited | London | 1971 |
| Alloy Art World Limited | London | 2010 |
| Alloy Core Trading Partners Ltd | Manchester | 2026 |
| Alloy Shine Ltd | London | 2025 |
| Alloya Biotechnology Co., Ltd | Beckenham | 2012 |
| Alloyplant Limited | Scarborough | 1994 |
| Allpab Limited | Dundee | 2014 |
| Allplant Hire Limited | Dunstable | 1995 |
| Allport Trustee Limited | Southall | 2020 |
| Allprt's Limited | London | 2024 |
| Allrains Group Company Limited | Beckenham | 2014 |
| Allroad Supply Chain Management Co., Ltd | Beckenham | 2016 |
| Allrock Limited | Maesteg | 2025 |
| Allround Services Ltd | London | 2025 |
| Allscot Securities Limited | Bridge Of Weir | 1977 |
| Allse Adventures Limited | Wolverhampton | 2024 |
| Allse Limited | Wolverhampton | 2024 |
| Allsecured Aluminium Solutions Ltd | Birmingham | 2020 |
| Allsop Electrical Ltd | Ashbourne | 2002 |
| Allsportz Limited | Newtown | 2021 |
| Allstaff Limited | Paisley | 1985 |
| Allstars Media Limited | Harrogate | 2026 |
| Allstone Fireplaces Limited | Stockport | 2010 |
| Allt K9 Ltd | Banchory | 2026 |
| Alltec Limited | Royston | 2016 |
| Alltek Global Ltd | London | 2013 |
| Alltohoop Limited | London | 2020 |
| Allton Contractors Limited | Ripon | 1937 |
| Allton Engineering Limited | Ripon | 1935 |
| Alltruck Zero Ltd | Nottingham | 2020 |
| Alltype Lettings Ltd | Bexley | 2017 |
| Allude Agency Limited | Dorking | 2020 |
| Allum's of Oxon Limited | Wallingford | 2022 |
| Allure Cloud Ltd | London | 2024 |
| Allure Fashions Limited | Exeter | 2003 |
| Allure Greens Holdings Ltd | Chelmsford | 2017 |
| Allure Lashes -Training & Aesthetics Ltd | Bolton | 2021 |
| Allurux Limited | Whiteley | 2017 |
| Allvalve Online Ltd | Worcester | 2012 |
| Allwood Machinery Limited | Maldon | 1984 |
| Allwood Timber Frames Limited | Taunton | 2008 |
| Ally Capellino Ltd | London | 2019 |
| ALM Property Services Limited | Northampton | 2008 |
| ALM Renovations Ltd | Amersham | 2023 |
| ALM Surveying Limited | Northampton | 2008 |
| Alma 1965 Limited | Aberdare | 2015 |
| Alma Capital Ltd | Bristol | 2014 |
| Alma Estates Ltd | Salford | 2017 |
| Alma F3M Consulting Ltd | London | 2014 |
| Alma Film Production Ltd | Farnham | 2023 |
| Alma Housing Limited | Chadwell Heath | 2024 |
| Alma Mater International Services Ltd | London | 2022 |
| Alma Property Management Limited | Enfield | 2004 |
| Alma Road Music Ltd | London | 2006 |
| Alma Serv Ltd | Milton Keynes | 2019 |
| Alma Superstore Limited | London | 2020 |
| Alma Veterinary Care Limited | Shrewsbury | 2009 |
| Alma's Ethical Cakes and Bakes Ltd | Elland | 2023 |
| Almaab Limited | London | 2020 |
| Almac (NO. 1) Limited | Craigavon | 2001 |
| Almac Clinical Services Trustees Limited | Craigavon | 2003 |
| Almac Diagnostics (2004) Limited | Craigavon | 2004 |
| Almac Trustees Limited | Craigavon | 2001 |
| Almada Productions Limited | Basildon | 2004 |