| Alexandra Gold Limited | London | 2014 |
| Alexandre Bruce Limited | London | 2013 |
| Alfajr Community Group CIC | Manchester | 2024 |
| Alfalaq Foundation CIC | Edgware | 2021 |
| Alfarah Hospital CIC | Leeds | 2025 |
| ALI Solutions 08 Ltd | Cardiff | 2020 |
| ALI Solutions 13 Ltd | Cardiff | 2020 |
| ALI Wahab Ltd | Maidstone | 2021 |
| Aliette Balay Ltd | Bridgnorth | 2022 |
| Alight Fire System Limited | Harrow | 2025 |
| Align and Mind Limited | Chelmsford | 2025 |
| Aligne Consultancy Ltd | London | 2025 |
| Alim Care Ltd | Liverpool | 2025 |
| Alimco Fire & Electrical Limited | Sutton Coldfield | 2021 |
| Alina Meyer Consulting Ltd | London | 2021 |
| Alina Quality Care Ltd | Bradford | 2025 |
| Alina&Care Service Limited | Ipswich | 2024 |
| Aline.Care Ltd | Ashton-Under-Lyne | 2022 |
| Alita Medical Services Ltd | Coventry | 2019 |
| Alite Fire Limited | London | 2024 |
| Alive Fire Limited | Bolton | 2016 |
| Aliyna Limited | Reading | 2024 |
| ALL Certs Safety Ltd | Newry | 2025 |
| ALL Day Safety Services Limited | St Ives | 2000 |
| ALL Ears ELY Ltd | Ely | 2023 |
| ALL Excelling Care and Education Limited | Enfield | 2025 |
| ALL Fire Services Ltd | Aylesbury | 2020 |
| ALL Ground Safety Group Ltd | London | 2025 |
| ALL in One Healthcare Limited | Maidenhead | 2025 |
| ALL Life Care Ltd | Liverpool | 2025 |
| ALL Nations Home Care Ltd | Walsall | 2024 |
| ALL Round Therapy Ltd | Maidstone | 2018 |
| ALL Your Safety Needs Limited | Deeside | 2024 |
| Allbans Ltd | Coventry | 2024 |
| Allens Consultancy Services Ltd | Leyland | 2020 |
| Alliance Fire Group Ltd | Newton Abbot | 2022 |
| Alliance First AID Training Academy Ltd | Glasgow | 2025 |
| Alliance for Choice Belfast Limited | Belfast | 2022 |
| Alliance Therapy Ltd | Nottingham | 2024 |
| Allie Campbell Limited | Henley-On-Thames | 2026 |
| Allied Service Transport Limited | Liskeard | 2022 |
| Allires Care Services Ltd | Walsall | 2023 |
| Allium Consulting Ltd | Salisbury | 2023 |
| Allmee Limited | Manchester | 2021 |
| Alloa First Limited | Alloa | 2009 |
| Allround Training Solutions Limited | Kington | 2022 |
| Allsopp Health Ltd | London | 2025 |
| Allyear Healthcaring Solutions Ltd | Derby | 2024 |
| ALM Administration and Business Support Ltd | Moreton-In-Marsh | 2021 |
| Alma Healthcare Services Ltd | Waltham Cross | 2018 |
| Alma-Mh Ltd | London | 2023 |
| Almaya Care Support Ltd | Northampton | 2025 |
| Almond Medical Limited | North Finchley | 2022 |
| ALP Fire Protection Limited | London | 2026 |
| ALP Professional Support Limited | Brecon | 2016 |
| Alpha & Omega Fire Stopping Limited | Bridlington | 2025 |
| Alpha Events and Stadium Management Ltd | Durham | 2017 |
| Alpha Fire Alarms Limited | London | 1996 |
| Alpha Fire Services Limited | Cannock | 2024 |
| Alpha Fire Solutions Ltd | Bolton | 2025 |
| Alpha Guard Security Ltd | London | 2025 |
| Alpha SIX Fire Door Consultancy Limited | Stockton-On-Tees | 2024 |
| Alpha Sprinkler Protection Ltd | Blackburn | 2014 |
| Alrt Fire & Security Ltd | Eastleigh | 2026 |
| Alsyra Ltd | Guildford | 2026 |
| Alterprivso Ltd | Durham | 2025 |
| Altha Global Services Limited | Glasgow | 2023 |
| Althevity Ltd | London | 2025 |
| Alti Procurements Ltd | Manchester | 2026 |
| Altiz Limited | Bracknell | 2023 |
| Altura Learning United Kingdom Limited | Beaconsfield | 2008 |
| Alura Care Ltd | Nottingham | 2026 |
| Always There Providing Care Ltd | Scarborough | 2025 |
| Alya Kevin Ltd | Plymouth | 2023 |
| Alyzain Limited | Wolverhampton | 2025 |
| AM Health Ltd | Wolverhampton | 2021 |
| AM Rathor Limited | Warrington | 2018 |
| Amaan Safety Limited | Swindon | 2025 |
| Amaby Care Limited | Coventry | 2020 |
| Amac Support Services Ltd | Bedford | 2025 |
| Amacs Services Ltd | Liverpool | 2019 |
| Amahle Healthcare Limited | Bootle | 2023 |
| Amai Mtoto CIC | London | 2022 |
| Amanah Educare Ltd | London | 2026 |
| Amanah Seds Limited | Sheffield | 2023 |
| Amanda's Home Support Ltd | Swansea | 2025 |
| Amaris Care Ltd | London | 2017 |
| Amazing Comfort Care Limited | Ashford | 2025 |
| Amazinglee Limited | Chatham | 2023 |
| Amber Fire Door Inspections Ltd | Glasgow | 2023 |
| Amber Ignis Limited | Hornchurch | 2026 |
| Amber Reports Ltd | Bury St. Edmunds | 2025 |
| Amberfern Care Ltd | London | 2025 |
| Ambition Safe Holding Ltd | Leicester | 2022 |
| AMBITION4FOOT Ltd | Durham | 2022 |
| Ambr.Zi Ltd | Bolton | 2022 |
| AME Solutions Ltd | Basildon | 2021 |
| Amed Regulatory Ltd | Porth | 2019 |
| Ameer Big Health Care Limited | Plymouth | 2025 |
| American Phoenix Ltd | St. Neots | 2020 |