| Argent Energy Limited | London | 2005 |
| Argent Fabrications Limited | Birmingham | 2000 |
| Argent Meat Traders Limited | Colchester | 1941 |
| Argent Shores Ltd | Leicester | 2026 |
| Argent Steel Limited | Sheffield | 1983 |
| Argent's Installations Ltd | London | 2019 |
| Argenta Dundee Limited | Glasgow | 2016 |
| ARGENTINA2022 Limited | Basildon | 2022 |
| Argento & Birch Limited | Stourport-On-Severn | 2026 |
| Argentum Apothecary Limited | Borehamwood | 2011 |
| Argentum Limited | Northampton | 1992 |
| Argex Limited | West Midlands | 1994 |
| Argier Structures Ltd | Clydebank | 2020 |
| Argie’S Cakes & Finger Foods Limited | Southampton | 2022 |
| Argin Ltd | Rotherham | 2022 |
| Argisol Building Systems Ltd | London | 2018 |
| Argles Metal Design Ltd | Southend On Sea | 2014 |
| Argo Aero UK Ltd | London | 2024 |
| Argo Applied Technologies Ltd | London | 2018 |
| Argo Foods Limited | Falkirk | 2003 |
| Argo Mobile Repair Team Limited | Ely | 2019 |
| Argo MRT Ltd | Waterlooville | 2025 |
| Argo Products Engineers Limited | Bolton | 1999 |
| Argo's Bakery Limited | Stromness | 1983 |
| Argo-Hytos Ltd | Buckingham | 1991 |
| Argobug Ltd | London | 2024 |
| Argolin Limited | Liphook | 1978 |
| Argon Electronics (UK) Ltd | Luton | 2010 |
| Argon Engineering (Airdrie) Limited | Airdrie | 1977 |
| Argon Joinery and Carpentry Ltd | London | 2018 |
| Argon Ltd | Letchworth Garden City | 2024 |
| Argon Refrigeration Services Ltd | Milton Keynes | 2015 |
| Argon Services UHV Limited | Forest Row | 2017 |
| Argon Welding Ltd | Poole | 2008 |
| Argonaut Group Ltd | Fawkham | 2025 |
| Argonaut Ventures Limited | Cheltenham | 2025 |
| Argosafe Limited | Mowsley | 2016 |
| Argosy Control Engineering Limited | Bridge Of Don | 1985 |
| Argosy Engineering Services Limited | Milton Keynes | 2016 |
| Argosy Machinery Limited | Glasgow | 1995 |
| Argraffwyr Gwynedd (Printers) Cyfyngedig | Caernarfon | 1979 |
| Argun Stationers Limited | | 2001 |
| Argus Fluidhandling Limited | St. Helens | 2008 |
| Argus Refrigeration Limited | Glasgow | 1965 |
| Argus Robotics Ltd | St. Leonards-On-Sea | 2026 |
| Argus Secure Limited | London | 2025 |
| Argyle Engineering Limited | Wirral | 1990 |
| Argyle Engineering Services Limited | Lancashire | 2003 |
| Argyle Metal Services (Scotland) Ltd. | Rhu | 2005 |
| Argyle Metals Limited | Farnham | 1978 |
| Argyle Power Engineering Ltd | Glasgow | 2021 |
| Argyle Street Joinery Limited | Lancashire | 2003 |
| Argyll and Bute Cosmetic Dentures Limited | Oban | 2015 |
| Argyll Bakeries Limited | Drumor, Campbeltown | 1978 |
| Argyll Borneo Consulting Ltd | Glasgow | 2020 |
| Argyll Botany Ltd | Tighnabruich | 2026 |
| Argyll Coffee Company Limited | Tighnabruaich | 2018 |
| Argyll Engineers Ltd | Oban | 2018 |
| Argyll Forest Products Limited | Dunoon | 2009 |
| Argyll Game Limited | Inveraray | 2021 |
| Argyll GT Craft Cars Limited | Anstruther | 2021 |
| Argyll Lager Limited | Oban | 2026 |
| Argyll Seafoods Limited | Argyll | 2003 |
| Argyll Smokery Limited | Dunoon | 2023 |
| Argyll Soft Drinks Co. Ltd | Helensburgh | 2026 |
| Argyll Spirits Co Ltd | Coatbridge | 2020 |
| Argyll Stonework Ltd | Witney | 2019 |
| Argylle Electronic Systems Ltd | Isleworth | 2024 |
| Argys Capital Ltd | London | 2019 |
| ARH Limited | Birmingham | 2022 |
| ARH Modular Homes Ltd | Hull | 2017 |
| ARH Portable Buildings Limited | Hull | 2023 |
| ARH Sports Equipment Ltd | Haverhill | 2016 |
| ARH Toiletries Ltd | Falkirk | 2019 |
| Arht Media (UK) Limited | London | 2019 |
| ARI CBD Ltd | London | 2019 |
| ARI Design Ltd | Cockfosters | 2023 |
| ARI Property Management Ltd | Blackburn | 2019 |
| ARI Scents Ltd | Rainham | 2025 |
| ARI Traders Limited | Manchester | 2017 |
| Ari&Lola Holding Ltd | London | 2020 |
| Aria & Avery Ltd | Pont-Y-Clun | 2024 |
| Aria Bakery Ltd | Salford | 2026 |
| Aria BE Ltd | Milton Keynes | 2020 |
| Aria Commercial Kitchens Ltd | Glasgow | 2016 |
| Aria Fabrics and Fine Furnishings Ltd | London | 2026 |
| Aria Food Limited | Middlesbrough | 2016 |
| Aria Horizons Limited | Edgware | 2016 |
| Aria London Ltd | Wembley | 2025 |
| Aria Therapeutics Ltd | London | 2026 |
| Aria&Co Limited | Scotland | 2025 |
| Ariah Noor Ltd | London | 2024 |
| Ariamson Group Limited | Cardiff | 2018 |
| Arian (Catering Suppliers) Limited | Manchester | 2014 |
| Arian EMS Limited | Ashington | 2017 |
| Arian Visual Solutions Limited | Grays | 2012 |
| Ariana Electrical Service Limited | Wembley | 2020 |
| Ariana Electronics Ltd | Hayes | 2025 |
| Ariane Ltd | Market Drayton | 2026 |
| Ariane Medical Systems Limited | Alfreton | 2004 |