| Advice Local Ltd | Nottingham | 2024 |
| Advice Space | Belfast | 1987 |
| Advice Support Knowledge Information | Croydon | 2012 |
| Advicemission Ltd | Aylesford | 2014 |
| Adviga Ltd | Isleworth | 2023 |
| Advil Ltd | London | 2019 |
| Advina Healthcare Limited | Pinner | 2021 |
| Advinia Care Homes Limited | London | 2017 |
| Advinia Health Care Limited | London | 1997 |
| Advinia Homes Limited | London | 2019 |
| Advis MED Ltd | London | 2025 |
| Advising Solutions Limited | Cardiff | 2026 |
| Advitalis Ltd | Cardiff | 2025 |
| Advo Health Limited | Fareham | 2024 |
| Advocacy After Fatal Domestic Abuse Ltd | Swindon | 2015 |
| Advocacy Care Ltd | Bury St. Edmunds | 2025 |
| Advocacy First | Bromley | 1998 |
| Advocacy Focus | Accrington | 2001 |
| Advocacy for ALL | Swanley | 1997 |
| Advocacy for Neuroacanthocytosis Patients | London | 2009 |
| Advocacy for YOU CIC | Stoke-On-Trent | 2024 |
| Advocacy Highland | Inverness | 2004 |
| Advocacy Matters (Wales) | Cardiff | 1996 |
| Advocacy Matters Ltd | Sutton Coldfield | 2012 |
| Advocacy Northeast | Blairdaff Inverurie | 2001 |
| Advocacy Service Aberdeen (A.S.A.) | Aberdeen | 1998 |
| Advocacy Services North East Wales Ltd | Mold | 2003 |
| Advocacy Support in Cymru Ltd | Cardiff | 2011 |
| Advocacy Supported Living Ltd | Derby | 2025 |
| Advocacy VSV | Newry | 2018 |
| Advocacyplus Ltd | Nottingham | 2013 |
| Advocare Healthcare Ltd | Deeside | 2025 |
| Advocare Limited | Bolton | 2016 |
| Advocate Better Care Ltd | London | 2020 |
| Advocate Care Services Ltd | Abingdon | 2015 |
| Advocate Collaborate Educate Limited | Mildenhall | 2025 |
| Advocate Residential Services Limited | Chester Le Street | 2020 |
| Advocates Guild International Ltd | Kington | 2025 |
| Advoccare | London | 2013 |
| Advoco Consultancy Services Ltd | Higherford | 2011 |
| Advonet | Leeds | 2001 |
| Advs Healthcare Ltd | Sheffield | 2024 |
| Adwals Company Limited | Newcastle Upon Tyne | 2013 |
| Adwan Limited | Chorley | 2021 |
| Adwenpa Services Ltd | Romford | 2020 |
| Adwick Aviation Medical Examiner Limited | Southport | 2015 |
| Adwileyuk Investment Limited | Wednesbury | 2016 |
| Adwo Group Ltd | London | 2023 |
| Adwoa Owusuaa Limited | Northampton | 2025 |
| ADWOAMANSAH85 Limited | London | 2023 |
| Adwodent Ltd | Dunstable | 2025 |
| Adwradiology Limited | Wilmslow | 2023 |
| ADY & Co Consults Ltd | Chelmsford | 2026 |
| ADY Centre Limited | London | 2015 |
| Adya Ltd | Norwich | 2021 |
| Adyama Makali Limited | Preston | 2024 |
| Adyan Care Ltd | Bradford | 2024 |
| Adyan K Ltd | Bradford | 2019 |
| Adyasa Ltd | Cuffley | 2026 |
| Adyol Healthcare Ltd | Harlow, Essex | 2025 |
| Adyush Services Ltd | Bedford | 2020 |
| Adz-I Consulting Limited | London | 2023 |
| Adzagw Ltd | Gravesend | 2022 |
| Adzamu Ltd | Ilford | 2023 |
| AE Anaesthetics Limited | London | 2020 |
| AE Care Group Ltd | Coventry | 2023 |
| AE Castle Limited | South Croydon | 2026 |
| AE Child & Family Consultancy Ltd | London | 2026 |
| AE Dent Limited | Manchester | 2012 |
| AE Dental Care Limited | Sheffield | 2026 |
| AE Dental Ltd | Leeds | 2022 |
| AE Diagnostics Ltd | Ipswich | 2019 |
| AE MED Limited | Leeds | 2022 |
| AE Medical Limited | Romford | 2007 |
| AE Optometry Limited | Dudley | 2015 |
| AE Osteopathy Ltd | Rochester | 2026 |
| AE Plastic Reconstructive Surgery Limited | Bridgend | 2022 |
| AE Pondenmar Ltd | Pontefract | 2021 |
| AE Shelters Ltd | Coventry | 2023 |
| AE Signature Aesthetics Ltd | Enfield | 2025 |
| AE Social Care and Education Limited | Basingstoke | 2014 |
| AE Solutions Services Limited | Wolverhampton | 2015 |
| AE Sports and Remedial Massage Ltd | Nottingham | 2017 |
| AE Therapy Ltd | Manchester | 2021 |
| AE Wellness Ltd | London | 2023 |
| Ae&Sa Limited | Coventry | 2023 |
| AEA Dental Ltd | West Sussex | 2014 |
| AEA Healthcare Ltd | London | 2023 |
| AEA Medical Ltd | High Wycombe | 2023 |
| AEA Optical Limited | London | 2016 |
| AEA Portmanteau Ltd | Barnet | 2013 |
| AEA Private Limited | Hamilton | 2022 |
| Aeaid Limited | Ellesmere Port | 2025 |
| Aeasa Ltd | Caerdydd | 2025 |
| AEB Care Ltd | Newtownards | 2014 |
| AEB Health Limited | Billingham | 2017 |
| AEB Investments Limited | Winchester | 2014 |
| AEB Social Care Limited | Reading | 2015 |
| Aebal Leisure Ltd | Nottingham | 2023 |
| Aeboncology Ltd | Cardiff | 2012 |