| Addspace Windows Limited | Westbourne | 2014 |
| Addstone Limited | Staffordshire | 2006 |
| Addtoketo Ltd | London | 2021 |
| ADE Enterprises Ltd | Swansea | 2015 |
| ADE Fantasi Ltd | Newport | 2020 |
| ADE Recruitment Group Limited | Sale | 2020 |
| Adebayo Ltd | Barking | 2021 |
| Adecor Co., Ltd | Kenilworth | 2019 |
| Adecrown Ltd | Doncaster | 2022 |
| Aded Engineering and Technologies Limited | Sleaford | 2024 |
| Adede UK Ltd | Taunton | 2015 |
| Adeel Global Services Ltd | Crewe | 2025 |
| Adegital Ltd | Coventry | 2023 |
| Adekoya UK Limited | Dagenham | 2021 |
| Adela Classic Quality Invest Limited | London | 2020 |
| Adela Funeral Homes Limited | Sutton Coldfield | 1981 |
| Adelade Ltd | Newhaven | 2024 |
| Adelaide Clinic Limited | York | 2010 |
| Adelaide Jase Consulting Ltd | Luton | 2021 |
| Adelaide Lawn Limited | Ilfracombe | 2015 |
| Adelaide Property Investment Limited | Belfast | 2015 |
| Adelaide Road 1963 Limited | Southampton | 2014 |
| Adelamead Ltd. | Thetford | 2007 |
| Adelante Ltd | London | 2016 |
| Adele Barnett Ltd | Stanmore | 2023 |
| Adele Carr Recruitment (EOT) Limited | Warrington | 2022 |
| Adelia Maritime Ltd | London | 2020 |
| Adeline Search Ltd | Manchester | 2023 |
| Adelola Aina Johnson Ltd | London | 2025 |
| Aden Stargate Ltd | Northolt | 2018 |
| Adenforth Limited | Bonnyrigg | 2002 |
| Adensouth Limited | London | 2008 |
| Adenstar SPV1 Limited | Brighton | 1988 |
| Adeola Abeni Labode Limited | Croydon | 2021 |
| Adeola Adekunle Popoola Ltd | Mildenhall | 2025 |
| Adeon Group Limited | Southampton | 2020 |
| Adeon Hospitality Limited | Southampton | 2020 |
| Adeon Media Limited | Southampton | 2020 |
| Adeon Spirits Limited | Southampton | 2020 |
| Adeps Lanae Limited. | Huddersfield | 1972 |
| Adept Arbitration Ltd. | London | 2024 |
| Adept Build Limited | Northampton | 2015 |
| Adept Consulting Solutions Ltd | London | 2011 |
| Adept Fencing and Decking Services Limited | London | 2021 |
| Adept Fire & Security Systems Limited | Wolverhampton | 2009 |
| Adept Fireplace Installations Ltd | Bristol | 2008 |
| Adept Mediation Ltd. | London | 2024 |
| Adept Safety Specialist Ltd | Northampton | 2022 |
| Adept Security Ltd | Radstock | 2006 |
| Adept Site Management Ltd | Batley | 2022 |
| Adept Vehicle Management Limited | Newcastle | 2014 |
| Adeptus Capital Investments Ltd | Ibstock | 2023 |
| Aderyn Y BWN Limited | Penarth | 2010 |
| ADF Developers Limited | Surrey | 2019 |
| ADF Direct Services Limited | Stoke-On-Trent | 2025 |
| ADF Group Ltd | Newcastle Under Lyme | 2020 |
| ADF Plumbing and Heating Ltd | Newcastle | 2024 |
| Adfal Ltd | East Knoyle | 2010 |
| Adfeeder Ltd | Cardiff | 2016 |
| Adfr Limited | Isleworth | 2020 |
| Adfs Limited | Stoke On Trent | 2009 |
| ADG Yachting Ltd | Blackpool | 2026 |
| Adhan Commercials PLC | Blackburn | 2013 |
| Adhd Focused Ltd | Glasgow | 2024 |
| ADI Developments Ltd | Chesterfield | 2010 |
| ADI Trans Logistics Ltd | South Ockendon | 2019 |
| Adina Chemicals Limited | Tunbridge Wells | 2019 |
| Adincentives Ltd. | Wilmslow | 2010 |
| Adips International Ltd | Sunderland | 2008 |
| Adips Training Ltd | Sunderland | 2008 |
| Adishay Company Limited | London | 2016 |
| Adiva Accountancy Ltd | Bromley | 2018 |
| Adixion Ltd | Dover | 2025 |
| Adjei-Amoah Ltd | Borehamwood | 2023 |
| Adjo Limited | London | 2024 |
| Adjoined Ltd | Coventry | 2024 |
| Adjust UK Limited | Llanymynech | 1991 |
| Adjust Your SET Holdings Limited | London | 2008 |
| Adjusters International Limited | London | 1987 |
| Adkhan Ltd | Glasgow | 2019 |
| ADL Lift Installations Limited | Bellshill | 2016 |
| Adlam Holdings Ltd | Woking | 2025 |
| Adler Consulting Sweden Limited | London | 2025 |
| Adlew 1963 Limited | Newcastle Upon Tyne | 2014 |
| Adlids Limited | Wrotham Heath | 1996 |
| Adlis & Atlantic Ltd | | 1999 |
| ADM Consulting Engineers Limited | London | 2009 |
| ADM India Holdings Limited | London | 2016 |
| ADM Northfield Ltd | Wetherby | 2010 |
| Admagnetics Limited | Accrington | 2007 |
| Admaison Ltd | London | 2024 |
| Admin Republic Limited | Holbeach | 2022 |
| Administration Saint Nicolas Ltd | London | 2008 |
| Admiral Developments Limited | High Wycombe | 1991 |
| Admiral Facilities Management Limited | Harrogate | 2025 |
| Admiral Homes (Eastern) Limited | High Wycombe | 1967 |
| Admiral Homes Limited | High Wycombe | 1988 |
| Admiral House Limited | Whitehaven | 2008 |
| Admiral Limited | London | 1979 |
| Admiral Mobility Ltd | Newton-Le-Willows | 2023 |