| AW Leisure Limited | Leighton Buzzard | 2020 |
| AW Limited | Crawley | 1966 |
| AW Skills Limited | Leighton Buzzard | 2020 |
| AWA Medi Limited | Birmingham | 2022 |
| Awaaz FM Community Radio CIC | Eastleigh | 2011 |
| Awadex 2 Limited | Salford | 2017 |
| Awadex Limited | Salford | 2016 |
| Awakening-Empire Limited | London | 2019 |
| Awan Marketing PLC | Birmingham | 2013 |
| Awar Ltd | Leeds | 2014 |
| Award Leisure Limited | Atherstone | 2024 |
| Award Visual Solutions Limited | Sheffield | 2008 |
| Awardbox Limited | Exeter | 2014 |
| Aware Group Ltd | Stoke-On-Trent | 2023 |
| Aware Hosting Ltd | Stoke-On-Trent | 2023 |
| Awarehouse Full Europe Ltd | Liphook | 2014 |
| Awareness Systems Limited | Manchester | 2012 |
| Awareness Therapy Limited | Preston | 2024 |
| Awarexpansion Ltd | Haverfordwest | 2025 |
| Awaters Limited | Reading | 2023 |
| Awayday Limited | London | 2014 |
| AWB Manchester Ltd | Ashton-Under-Lyne | 2025 |
| AWD Soft Limited | Broadstairs | 2023 |
| Awdis Limited | Carpenders Park | 2013 |
| Awdry Close 1958 Limited | Calne | 2015 |
| AWE Energy Services Limited | Sheffield | 2014 |
| Awed-Global Ltd | London | 2024 |
| Awen ETC Ltd | Cambridgeshire | 2022 |
| Awendiesel Power Co., Ltd | Beckenham | 2012 |
| Awendio Ltd | London | 2021 |
| Awesome ELM Trustees Limited | London | 2016 |
| Awesome Equine Limited | Frodsham | 2022 |
| Awesome Foursome Limited | Hemel Hempstead | 2016 |
| Awesome Source Games Limited | Epsom | 2025 |
| Awesome Supplements Limited | Ipswich | 2016 |
| Awesomesparks Ltd | London | 2019 |
| AWF Group (Devon) Limited | Bridgwater | 2013 |
| AWG Outlet Centers Limited | Edinburgh | 1998 |
| AWG Property Director Limited | Huntingdon | 2005 |
| Awgraham Ltd | Stockton-On-Tees | 2023 |
| Awhy Investment Ltd | Oxford | 2021 |
| Awinyear Co., Ltd | Cambridge | 2020 |
| AWL Solutions Invest Limited | London | 2025 |
| Awlc Limited | London | 2017 |
| AWM Electrical (Scotland) Ltd | Broxburn | 2019 |
| AWM Onsite Limited | Ripon | 2014 |
| AWM Survey Equipment Limited | York | 2009 |
| AWM Technologies Limited | Dunmow | 2014 |
| Awnings Online Ltd | Wellingborough | 2024 |
| Aworth Realisations | Uckfield | 1963 |
| AWS Diagnostics Limited | Coventry | 2021 |
| AWS Renewables Ltd | Wick | 2008 |
| Awsom Ltd | Tunbridge Wells | 2015 |
| Awsome Ltd | Harrogate | 2012 |
| Awssun Co., Ltd | Beckenham | 2016 |
| Awtua Limited | Penrith | 2016 |
| AX Automotive Limited | Birmingham | 2004 |
| Axan Ltd | Wigston | 2023 |
| Axcess (UK) Limited | Cobham | 2019 |
| AXE Global Limited | London | 2024 |
| AXE Limited | Edinburgh | 2000 |
| AXE Recruitment Limited | Gosport | 2017 |
| Axel Apex Capital Ltd | Wembley | 2025 |
| Axel Springer International Group Limited | London | 1999 |
| Axel Springer Publishing International Limited | London | 1999 |
| Axel Springer TV International Limited | London | 1998 |
| Axel Yachting Limited | London | 2025 |
| Axelmark Limited | London | 2010 |
| Axelyra Virexo Services Ltd | Manchester | 2026 |
| Axentra Optrixa Trading Ltd | Manchester | 2026 |
| Axepoint Energy Limited | London | 2020 |
| Axeus Capital Limited | Bridgwater | 2007 |
| Axeus Residential Croydon Limited | Bridgwater | 2016 |
| Axeus Residential Limited | Bridgwater | 2016 |
| Axford Group Limited | Bradford On Avon | 2021 |
| Axguru Limited | Hornchurch | 2017 |
| Axholme Garage Limited | Doncaster | 2016 |
| Axia Valuation Services Limited | Ingatestone | 2015 |
| Axial Builders Limited | London | 2022 |
| Axima FM Holding Limited | Newcastle Upon Tyne | 1998 |
| Axima FM Limited | Newcastle Upon Tyne | 1994 |
| Aximor for International Services Limited | Manchester | 2026 |
| Axinor Norvix Systems Ltd | Manchester | 2026 |
| Axiom Advice & Counsel Limited | London | 2022 |
| Axiom Initiatives Limited | Stevenage | 2024 |
| Axion Consulting Limited | Manchester | 2006 |
| Axion Energy Limited | Liverpool | 2009 |
| Axion Engineering Limited | Liverpool | 2010 |
| Axion Polymers Limited | Liverpool | 2007 |
| Axiro Novexa Solutions Ltd | Manchester | 2026 |
| Axiro Ventures Ltd | Manchester | 2026 |
| Axis Art Limited | Ilkeston | 2022 |
| Axis Builders Ltd | Stonehouse | 2015 |
| Axis Business Consulting Limited | Ballynahinch | 2012 |
| Axis Business Park Liverpool Limited | London | 2006 |
| Axis Business Park Management Company Limited | London | 2006 |
| Axis Engraving Ltd | London | 2025 |
| Axis Fire Sprinklers Ltd | Bath | 2023 |
| Axis Red-Green Ltd | London | 2022 |
| Axis Topco Limited | Pudsey | 2015 |