| Aptar UK Limited | Leeds | 1979 |
| Aptec Engineers (Burton) Limited | Swadlincote | 1995 |
| Aptec Products Limited | West Auckland | 2006 |
| Aptec Technologies Limited | Bournemouth | 1995 |
| Aptim Ltd | Chelmsford | 2023 |
| Aptisens Ltd | Wolverhampton | 2014 |
| Aptiv Services UK Limited | Crawley | 1993 |
| Aptivolt Limited | London | 2013 |
| Apto-Gen Limited | Sutton Coldfield | 2019 |
| Apton Partitioning Limited | Coseley | 2006 |
| Aptuit (Oxford) Limited | Abingdon | 2011 |
| Aptus Technical Solutions Limited | Aberdeen | 2022 |
| Aptv Limited | Solihull | 2003 |
| Apuan Stone Limited | London | 2020 |
| Apuljack Electronics Ltd | Highbridge | 2014 |
| Apuries Services Limited | Ettingshall, Wolvehampton | 2007 |
| Apus Nova Ltd | London | 2025 |
| APW Coachworks Limited | Bridgend | 1993 |
| APX Fire & Security Limited | Hastings | 2003 |
| AQ Wiring Systems Rockford Ltd | Woodbridge | 1984 |
| Aq&A Limited | Derby | 2024 |
| Aqatin Canada Processing Limited | London | 2025 |
| Aqdot Limited | Cambridge | 2012 |
| Aqil Martial Arts Ltd | Edinburgh | 2026 |
| Aqiyl Akram Limited | London | 2026 |
| Aqlaperlis Jewellery Limited | London | 2024 |
| AQM Ltd | Ivybridge | 2026 |
| AQM Spinning Limited | Nuneaton | 2012 |
| AQM Trading Ltd | London | 2024 |
| Aqms Electrical Ltd | Horsham | 2022 |
| Aqord Limited | Chester | 2006 |
| Aqpd Limited | London | 2016 |
| Aqsa Cola Limited | Bradford | 2024 |
| Aqsa Meat Ltd | Bolton | 2022 |
| Aqua Aeration Systems Ltd | Rayleigh | 2022 |
| Aqua Air Limited | Huddersfield | 1994 |
| Aqua Allies Ltd | Orton Southgate, Peterborough | 2010 |
| Aqua Bioscience Limited | Wigan | 2012 |
| Aqua Blast Scotland Ltd | Edinburgh | 2019 |
| Aqua Bliss Drinks Limited | Birmingham | 2019 |
| Aqua Blue Design Limited | Essex | 2003 |
| Aqua Broadcast Limited | Chessington | 2020 |
| Aqua Coatings Limited | West Midlands | 1995 |
| Aqua Destillata Ltd | Romford | 2025 |
| Aqua Detox USA Ltd | High Wycombe | 2012 |
| Aqua Dynamics Limited | Luton | 2007 |
| Aqua Electrical Limited | Castle Douglas | 2026 |
| Aqua Energy Saving Systems Ltd | Lincoln | 2017 |
| Aqua Fabrications Limited | Skelmersdale | 1988 |
| Aqua Free Solutions Ltd | London | 2016 |
| Aqua Geocomposites Limited | Skelmersdale | 1989 |
| Aqua Glass Mirror Ltd | Bolton | 2025 |
| Aqua Glow Drink Ltd | London | 2024 |
| Aqua GOD Limited | London | 2025 |
| Aqua Hebrides Limited | Ellon | 2016 |
| Aqua Hygiene Products Limited | Chester | 1997 |
| Aqua Kote Systems Limited | Tonbridge | 1997 |
| Aqua Laboratories Limited | Coventry | 2013 |
| Aqua Labs Chemicals Ltd | Market Rasen | 2019 |
| Aqua Metrology Systems Limited | Salford | 2010 |
| Aqua MIX Ltd | Chichester | 2023 |
| Aqua Moringa Ltd | London | 2022 |
| Aqua Munda Ltd | London | 2021 |
| Aqua Narrowboats (MFG) Limited | Derby | 2023 |
| Aqua Natural Limited | Wellingborough | 1988 |
| Aqua Nero Marine Ltd | Truro | 2022 |
| Aqua Nordica Ltd | London | 2022 |
| Aqua NOW Group Limited | London | 2025 |
| Aqua Oleum Limited | Stroud | 2015 |
| Aqua Plastics Limited | Castleford | 2009 |
| Aqua Signal & Telegraphic Systems Ltd | Skelmersdale | 1994 |
| Aqua Soft Water Care Ltd | London | 2025 |
| Aqua Spas Ltd | Barry | 2011 |
| Aqua Systems (U.K.) Limited | Kilmacolm | 2017 |
| Aqua Teknik Limited | | 2005 |
| Aqua Valve Limited | Bury | 2009 |
| Aqua Vera Limited | Witham | 2026 |
| Aqua Verdant Ltd | Oldham | 2024 |
| Aqua Vitae Technologies Limited | London | 2020 |
| Aqua Vital Limited | London | 2024 |
| Aqua Water Systems Limited | Kidderminster | 1985 |
| Aqua Wings Technology Co., Ltd | Beckenham | 2022 |
| Aqua Yachts Group Ltd | Lymington | 2019 |
| Aqua Zeta Pharma Ltd | West Drayton, Harmondsworth | 2025 |
| Aqua-Bio UK Limited | Stoke-On-Trent | 2001 |
| Aqua-Clim Contract Services Limited | Swanley | 2005 |
| Aqua-Dock Limited | Tewkesbury | 2008 |
| Aqua-Gas Manufacturing Limited | Corby | 1983 |
| Aqua-Logic Controls Ltd | Manchester | 2025 |
| Aqua-Marine Services Ltd | Portsmouth | 2017 |
| Aqua-Mech Solutions Ltd | Cookstown | 2014 |
| Aqua-Response Limited | Lincoln | 2006 |
| Aqua-Tractor Limited | Shaftesbury | 2023 |
| Aqua-Tunnel Ltd | Stafford | 2025 |
| AQUA50 Limited | Leicester | 2015 |
| Aquabeach Yachting Ltd | Lancing | 2021 |
| Aquablast Limited | Beccles | 1988 |
| Aquablast Systems Limited | Telford | 2008 |
| Aquablock Limited | Welwyn Garden City | 2023 |
| Aquabond Limited | Runcorn | 2002 |