| Alpha Cereals Unlimited | Griffiths Way, St Albans | 1961 |
| Alpha Chemitech Co., Ltd | Beckenham | 2010 |
| Alpha City Unitech Ltd | Birkenhead | 2025 |
| Alpha Claygate Ltd | Teddington | 2014 |
| Alpha Clinical Developments Limited | Salford | 2012 |
| Alpha Clinical Limited | Hemel Hempstead | 2015 |
| Alpha Collectables Ltd | Coventry | 2026 |
| Alpha Commerce Ltd | Broxbourne | 2003 |
| Alpha Commercial Enterprises Ltd | High Wycombe | 2022 |
| Alpha Commercial Management Ltd | Bromsgrove | 2023 |
| Alpha Commodity Solutions Limited | Salisbury | 2017 |
| Alpha Construction (Developments) Limited | Hilton | 2007 |
| Alpha Construction (PVT) Ltd | Slough | 2013 |
| Alpha Consult Limited | Edinburgh | 2012 |
| Alpha Consultancy MS Limited | Southampton | 2023 |
| Alpha Consultants ( London ) Ltd | London | 2023 |
| Alpha Consultants (UK) Ltd | London | 2013 |
| Alpha Consultants Group Ltd | London | 2023 |
| Alpha Consulting Services Ltd | Glasgow | 2026 |
| Alpha Content Ltd | London | 2011 |
| Alpha Contract Management Ltd | London | 2008 |
| Alpha Contract Solutions Limited | Bishop'S Stortford | 2024 |
| Alpha Controls Limited | Gerrards Cross | 1999 |
| Alpha Corporate Training Services Limited | Polegate | 2012 |
| Alpha Corporation Limited | Harrow | 1983 |
| Alpha CRC Limited | Cambridge | 1987 |
| Alpha Creative Design Ltd | Chorley | 2020 |
| Alpha Credit Advisors Limited | London | 2023 |
| Alpha Credit Repair Limited | London | 1996 |
| Alpha Crucis Solutions Ltd | Bristol | 2019 |
| Alpha CTI Ltd | Lancing | 2012 |
| Alpha Cyber Limited | Corsham | 2024 |
| Alpha Cybernetics UK Ltd | Nottingham | 2025 |
| Alpha Deal Group Ltd | London | 2016 |
| Alpha Design Agency Ltd | Frinton-On-Sea | 2023 |
| Alpha Design Ltd | Kingswinford | 2004 |
| Alpha Design Products Ltd | Exeter | 2020 |
| Alpha Design Studio Limited | Sittingbourne | 2013 |
| Alpha Development (Europe) Ltd | London | 2020 |
| Alpha Development Group Ltd | London | 2020 |
| Alpha Development Partnership Ltd | London | 2003 |
| Alpha Developments (UK) Limited | Whalley, Clitheroe | 2005 |
| Alpha Digiai Accountants Ltd | London | 2026 |
| Alpha Digital Group Limited | Bolton | 2022 |
| Alpha Digitek Solutions Ltd | Middlesex | 2018 |
| Alpha Dispensing Support Services Limited | Bridlington | 2021 |
| Alpha DLT Ltd | Market Harborough | 2021 |
| Alpha Domain Development Ltd | Doncaster | 2008 |
| Alpha Echo Mike Ltd | Bishop'S Stortford | 2025 |
| Alpha Edge Capital Ltd | London | 2025 |
| Alpha Electrical Solutions Ltd | Andover | 2026 |
| Alpha Elite Group Limited | Croydon | 2017 |
| Alpha Empires Group Ltd | Hinderwell | 2019 |
| Alpha Energy Assessors Ltd | St. Albans | 2009 |
| Alpha Energy Consulting Limited | Northampton | 2014 |
| Alpha Engineering (Selby) Limited | Selby | 2013 |
| Alpha Engineering Consultancy Ltd | Stonehaven | 2022 |
| Alpha Engineering Consultants Ltd | London | 2021 |
| Alpha Engineers Ltd | London | 2022 |
| Alpha Engraving Limited | Morecambe | 2014 |
| Alpha Enigma Limited | London | 2012 |
| Alpha Enterprise Solutions Limited | Cambridge | 2024 |
| Alpha Epsilon Ltd | Stanmore | 2008 |
| Alpha Equinox Ltd | Roslin | 2023 |
| Alpha ESG Consulting Ltd | London | 2023 |
| Alpha Europe Services Limited | London | 2021 |
| Alpha EV Solutions (UK) Ltd | Reigate | 2023 |
| Alpha Experience Design Limited | Altrincham | 2023 |
| Alpha Experts Ltd | Hyde | 2024 |
| Alpha Eyecare Holdings Limited | Wolverhampton | 2017 |
| Alpha Finance Services Limited | Middlesex | 2007 |
| Alpha Finance Solutions Ltd | London | 2020 |
| Alpha Financial Markets Consulting Group Limited | London | 2010 |
| Alpha Financial Markets Consulting Mena Limited | London | 2023 |
| Alpha Financial Markets Consulting UK Limited | London | 2003 |
| Alpha Financial Partners Ltd | Dagenham | 2016 |
| Alpha Financial Services Group Ltd | Luton | 2026 |
| Alpha Fire Engineering Ltd | Iver | 2011 |
| Alpha Fireplaces & Design Ltd | Glasgow | 2009 |
| Alpha Flex 2.0 Ltd | Sidcup | 2024 |
| Alpha Flight Group Limited | Manchester | 1994 |
| Alpha FMC Bidco Limited | London | 2015 |
| Alpha FMC Trustee Limited | London | 2017 |
| Alpha Focus Limited | London | 2024 |
| Alpha Foxtrot Solutions Limited | Horsham | 2021 |
| Alpha Fruit Limited | Borough Green | 1978 |
| Alpha Garden Centre Limited | Essex | 1980 |
| Alpha GEN Consultants Ltd | London | 2025 |
| Alpha GG Inspection and Engineering Services Ltd | London | 2025 |
| Alpha Global Advisors Limited | London | 2017 |
| Alpha Global Group Ltd | Enfield | 2019 |
| Alpha Global Steel Technologies Limited | London | 2006 |
| Alpha Global Ventures Limited | Edinburgh | 2006 |
| Alpha Governance Partners Limited | London | 2015 |
| Alpha Graphic & Marketing UK Limited | London | 2020 |
| Alpha Green Energy Ltd | Bradford | 2024 |
| Alpha Hale Consultancy Ltd | London | 2020 |
| Alpha Hale Ltd | London | 2019 |
| Alpha Health Partners Limited | Beverley | 2025 |
| Alpha Health Physics Limited | Wick | 2018 |