| Aqua Environmental Maintenance Ltd | Huntingdon | 2018 |
| Aqua Environmental Systems Limited | Huntingdon | 2011 |
| Aqua Flow Drainage Ltd | London | 2025 |
| Aqua Force Special Waste Limited | Wolverhampton | 1997 |
| Aqua Legion UK. Limited | London | 2006 |
| Aqua Mundus Limited | Bidford On Avon | 2012 |
| Aqua Nero (Water and Energy) Ltd | Truro | 2023 |
| Aqua Projects Limited | Motherwell | 2002 |
| Aqua Pure Vitality Ltd | Daventry | 2023 |
| Aqua Regia Ltd | Wolverhampton | 2022 |
| Aqua ROD (South West) Limited | Cornwall | 2003 |
| Aqua ROD Lista Drain (UK) Limited | Shipley | 2008 |
| Aqua Services (UK) Limited | Bury | 2013 |
| Aqua Smart Water Treatment Ltd | Orpington | 2019 |
| Aqua Surge Ltd | Derby | 2026 |
| Aqua Systems Ltd | London | 2025 |
| Aqua Techniques Limited | Leeds | 2020 |
| Aqua Washroom Solutions Ltd | Bristol | 2007 |
| Aqua-Dyn Ltd | Salisbury | 2019 |
| Aqua-Flow Environmental Ltd. | Woking | 2023 |
| Aquablast Services Limited | Bury | 2001 |
| Aquacair Ltd | Chichester | 1999 |
| Aquacare Limited | Haywards Heath | 2003 |
| Aquacell Ltd | London | 2024 |
| Aquacity NAV Ltd | London | 2024 |
| Aquaclear SC Ltd | Edinburgh | 2009 |
| Aquafilta Limited | Bury St. Edmunds | 2014 |
| Aquafine (UK) Ltd | Alton | 2012 |
| Aquafitting (UK) Limited | Leicester | 2014 |
| Aquafix Water & Electrics Ltd | Carmarthen, | 2005 |
| Aquajen Environmental Services Ltd | Aldershot | 2021 |
| Aquajet Drain Cleaning Limited | Newcastle Upon Tyne | 2001 |
| Aquajet Drainage Ltd | Crowthorne | 2023 |
| Aqualance Compliance Ltd | Teignmouth | 2025 |
| Aqualibrium SAF Corsia Ltd | London | 2025 |
| Aquamatch Water Treatment Limited | London | 2023 |
| Aquamate Limited | Wallasey | 2020 |
| Aquamoni UK Ltd | Hitchin | 2024 |
| Aquanova Water Solutions Limited | London | 2025 |
| Aquapure Systems Ltd | London | 2025 |
| Aquarity Ltd | Reading | 2026 |
| Aquarius Limited | Brierley Hill | 2008 |
| Aquarius Waste Management Limited | Burnett | 2007 |
| Aquarod Ltd | Stanley | 2021 |
| Aquasafecomplianceservices Ltd | London | 2026 |
| Aquasense AI Solutions Ltd | Birmingham | 2025 |
| Aquasense-Ai Ltd | Birmingham | 2025 |
| Aquaserv Limited | Widnes | 2005 |
| Aquaserve Engineering Limited | Matlock | 2008 |
| Aquashebah Ministries | Leeds | 2014 |
| Aquasoft Systems Limited | Telford | 2013 |
| Aquasol Engineering (UK) Co., Limited | Brighton | 2021 |
| Aquaspeed Limited | Manchester | 1998 |
| Aquassist Ltd | Hereford | 2005 |
| Aquastal Limited | High Wycombe | 1983 |
| Aquastream Water Softeners Ltd | Cambridge | 2011 |
| Aquasure Solutions Ltd | Brackley | 2025 |
| Aquaswift Limited | Telford | 2005 |
| Aquatech Drain Services Limited | Henfield | 2013 |
| Aquatech Environmental Services Limited | Wolverhampton | 1999 |
| Aquatech Water Treatment Products and Services Ltd | Surrey | 2002 |
| Aquathin UK Ltd | Guildford | 2019 |
| Aquatight Roofing Ltd | Preston | 2024 |
| Aquatreat Environmental Products Ltd | Southam | 2007 |
| Aquavida Limited | Chepstow | 2002 |
| Aquayell Ltd | Bury St. Edmunds | 2023 |
| Aquevo Limited | Manchester | 2017 |
| Aquevo London Ltd | Manchester | 2022 |
| Aquifer Water Filtration Ltd | Newton Abbot | 2024 |
| Aquila Waste Management Solutions Limited | Shetland | 2022 |
| Aquilae Holdings Ltd | Bexhill-On-Sea | 2014 |
| Aquiva Foundation | Richmond | 2011 |
| Aqwise UK Limited | Staffordshire | 2019 |
| AR Metal Recycling Ltd | Portsmouth | 2017 |
| AR Recycling (Somercotes) Ltd | Alfreton | 2022 |
| AR Removals AL Ltd | London | 2025 |
| AR Treatment Ltd | Accrington | 2026 |
| AR Waste Ltd | Ventnor | 2022 |
| AR Water Services Limited | Ammanford | 2023 |
| Arad Metering Services (UK) Limited | Hereford | 2007 |
| Aralam Limited | Buckinghamshire | 2004 |
| ARB London Ltd | Bromley | 2018 |
| ARC Asbestos Removal & Surveys Ltd | Taunton | 2023 |
| ARC Facilities South East Ltd | Maidstone | 2020 |
| ARC Industries Group Limited | London | 2021 |
| ARC Waste Services Ltd | New Malden | 2025 |
| Arca Heavy Engineering Ltd | Maghera | 2018 |
| Arcade Warehouse Ltd | Pontefract | 2002 |
| Arcams Limited | Manchester | 2025 |
| Archana Ltd | Cottingham | 2025 |
| Archer Recycling Limited | Cheltenham | 2012 |
| Archers Environmental Solutions Ltd | Sheffield | 2025 |
| Archers Fields Energy Recovery Limited | Leigh On Sea | 2020 |
| Arches Hall Estate Water Limited | London | 2024 |
| Archie's Jetting Services Ltd | Bristol | 2024 |
| Archimedes Metals Limited | Portsmouth | 2003 |
| Architectural Woodcraftsmen Limited | Southernhay West | 1964 |
| Archwade Limited | Stockton-On-Tees | 2017 |
| Arcis Resource Group Ltd | Swadlincote | 2025 |
| Arcpool Limited | Broadstairs | 2023 |