| A B M Grouper Limited | Ilford | 1990 |
| A B Medical Services (UK) Limited | Chiddingfold | 2013 |
| A B Medics (UK) Ltd | Lutterworth | 2011 |
| A B Optical Limited | Nottingham | 2004 |
| A B Optics Limited | Sutton Coldfield | 2005 |
| A B Sarfo Ltd | Kent | 2021 |
| A B Stephen Limited | Wilmslow | 2010 |
| A B Williams Limited | Lincoln | 2009 |
| A Bader Ltd | Huddersfield | 2025 |
| A Bains Locum Services Limited | Willenhall | 2018 |
| A Bakht Limited | Coventry | 2024 |
| A Balanced Life Therapies Limited | London | 2023 |
| A Banerjee Ltd. | Stockton-On-Tees | 2010 |
| A Baria Limited | Manchester | 2023 |
| A Bashir Limited | Walsall | 2013 |
| A Bath Consulting Limited | Washington | 2023 |
| A Battrick Podiatrist Limited | Llantwit Major | 2006 |
| A Beaudon UK Limited | Preston | 2024 |
| A Beautiful YOU Ltd | London | 2017 |
| A Belfield Limited | Isleworth | 2014 |
| A Better Carehome (Westerham) Ltd | Hampton | 2024 |
| A Better Carehome Ltd | Hampton | 2011 |
| A Better Step Limited | North Ferriby | 2009 |
| A Better Tomorrow C.I.C. | Telford | 2013 |
| A Better Way Counselling Service Ltd | Gaerwen | 2025 |
| A Better YOU SB Ltd | Birmingham | 2024 |
| A Bettercare Solution Ltd | Tilbury | 2022 |
| A Binder Limited | Wootton Bridge | 2016 |
| A Binney Dental Surgery Limited | Cardiff | 2010 |
| A Bite of Life Limited | Caerphilly | 2020 |
| A Bobat Care Ltd | Blackburn | 2025 |
| A Bradleey Limited | London | 2026 |
| A Breath for Life Childrens Charity | Morecambe | 1998 |
| A Breath of Fresh Air Gwynedd Ltd | Porthmadog | 2021 |
| A Breathing Space CIC | Offerton | 2025 |
| A Bridge to Living Limited | London | 2021 |
| A Bright Place Ltd | Grangemouth | 2024 |
| A Bright Start Nursery (Rumney) Limited | Cardiff | 2013 |
| A Brighter Path CIC | High Wycombe | 2025 |
| A Brightway Ltd | Welling | 2025 |
| A Brightway Support Ltd | Welling | 2025 |
| A Butt Physiotherapy Limited | Bolton | 2001 |
| A C Bowen Ltd | Ellesmere Port | 2026 |
| A C Dental Laboratories Limited | Malton | 2008 |
| A C F Child Psychology Ltd | Bristol | 2023 |
| A C Fialho Limited | Eastbourne | 2026 |
| A C GEE Limited | Wellingborough | 2009 |
| A C Howson Ltd | Leeds | 2025 |
| A C Inta Care Ltd | Gateshead | 2019 |
| A C Locum Services UK Ltd | Cradley Heath | 2023 |
| A C Mcintosh Limited | Birmingham | 2026 |
| A C Musonda Limited | Waltham Abbey | 2023 |
| A C Optics Limited | Walsall | 2006 |
| A C Pathology Limited | Radyr | 2019 |
| A C Podiatry Limited | Cramlington | 2024 |
| A C Redfern Limited | Exeter | 2019 |
| A C Robertson Medical Limited | Inverness | 2019 |
| A C S Care Services Ltd | Milton Keynes | 2003 |
| A C Tidman Limited | West Sussex | 2021 |
| A Campbell Healthcare Ltd | London | 2022 |
| A Care Kompany Limited | Nelson | 2023 |
| A Care Limited | Bury | 2024 |
| A Care SOLUTION5 Ltd | Darwen | 2022 |
| A Caring Companion Ltd | Malmesbury | 2024 |
| A Caring Company Limited | Dunstable | 2010 |
| A Caring Heart Ltd | Eastbourne | 2023 |
| A Centered U Therapy Ltd | Kington | 2026 |
| A Chamberlain Medical Ltd | Hailsham | 2021 |
| A Chance for Life Limited | Penrith | 2002 |
| A Chandra Limited | Newcastle Upon Tyne | 2017 |
| A Chavez Ltd | Plymouth | 2019 |
| A Childs Journey Ltd | Market Harborough | 2025 |
| A Choudhry & Co Ltd | Nottingham | 2015 |
| A Class Care Limited | Papworth Everard | 2012 |
| A Class Dental Limited | London | 2021 |
| A Class Services Ltd | London | 2020 |
| A Clayton Ltd | Birmingham | 2016 |
| A Clear Way Ltd | London | 2025 |
| A Clinique Limited | Buckhurst Hill | 2021 |
| A Collins Optometry Ltd | Manchester | 2018 |
| A Counsell (Cheshire) Limited | Barry | 2019 |
| A Covaci Ltd | Exeter | 2015 |
| A Cowell Ltd | Southend-On-Sea | 2019 |
| A Craig Solutions Ltd | Taffs Well | 2024 |
| A Cruceanu Ltd | Hove | 2013 |
| A Cube Consultancy Limited | Borehamwood | 2009 |
| A Cubed Pharma Limited | Luton | 2015 |
| A D Acupuncture Ltd | Brockley | 2026 |
| A D Aesthetics Pharmacist Ltd | Sherborne | 2023 |
| A D KAY Limited | Wilmslow | 2019 |
| A D R Schofield Limited | Shrewsbury | 2019 |
| A D Richards Limited | Haverfordwest | 2003 |
| A D V Canterbury Limited | Canterbury | 2008 |
| A Dadhiwala Limited | Darwen | 2010 |
| A Darakhshan Ltd | Lincoln | 2014 |
| A Davies (Warrenpoint) Ltd | Warrenpoint | 2018 |
| A Davies Knee Surgery Limited | Swansea | 2026 |
| A DE Beer Contracts Limited | London | 2012 |
| A Dean Limited | Nottingham | 2016 |
| A Deeper Shade of Blue Ltd | Brighton | 2024 |