| Advanced Animal Health Limited | Thetford | 2005 |
| Advanced ARB Limited | Harlington Hayes | 2001 |
| Advanced Arboriculture Limited | Exeter | 2017 |
| Advanced Arboriculture Training Ltd | Blackpool | 2019 |
| Advanced Barn Comfort Ltd | Monmouth | 2020 |
| Advanced Cladding Installations Limited | Mansfield | 1997 |
| Advanced Consultants Limited | Twyford | 2007 |
| Advanced Farming Ltd | Manchester | 2021 |
| Advanced Growers Ltd | Liverpool | 2020 |
| Advanced Landscaping Services Limited | Ruislip | 2006 |
| Advanced Management Services (UK) Ltd | Liskeard | 2018 |
| Advanced Organics West Midlands Ltd | Stourbridge | 2023 |
| Advanced Tree Care Limited | Doncaster | 2001 |
| Advanced Tree Services Limited | London | 1997 |
| Advanced Tree Surgeons Limited | Ruislip | 2021 |
| Advanced Tree Surgery Limited | Nuneaton | 2026 |
| Advanced Trees Ltd | Dunoon | 2026 |
| Advanced Woodland Services Ltd | Frome | 2002 |
| Advanta Seeds Holdings UK Ltd | Warrington | 2021 |
| Advent Farms Ltd | Northampton | 2023 |
| Ady's Wood Splitting Services Ltd | Cromer | 2014 |
| AE & E Garnett Ltd | Millom | 2012 |
| AE & GM Jones Limited | Welshpool | 2015 |
| AE & PC Capstick Ltd | Morecambe | 2020 |
| AEA (East Midlands) Ltd | Ashbourne | 2021 |
| Aeko Ltd | Horsham | 2021 |
| AEL Y Bryn Farm Limited | Welshpool | 2024 |
| Aeolus Group Limited | Ventnor | 2017 |
| Aeonis Limited | Preston | 2014 |
| Aerial Applications Limited | Nantwich | 2024 |
| Aerial Aspect Imaging Ltd. | Nottingham | 2014 |
| Aerial Tree Services Ltd | Wimborne | 2004 |
| Aero AG Ltd | Bath | 2026 |
| Aero Angel Ltd | London | 2025 |
| Aero M Ltd | Peterhead | 2017 |
| Aero Signature Services Ltd | Nottingham | 2025 |
| Aero-Crop Solutions Ltd | Wrexham | 2019 |
| Aeroanalytics Ltd | Perth | 2024 |
| Aeroarb Solutions Ltd | Colchester | 2020 |
| Aerogrow Limited | Wirral | 2025 |
| Aeroponic Systems Limited | Corby | 2012 |
| Aerosurf Limited | Edinburgh | 1998 |
| Aerovex Ltd | Haywards Heath | 2026 |
| AES and SON Farming Limited | Pontypridd | 2021 |
| Aether Credit Management Limited | London | 2024 |
| Aether Farms Holdings Ltd | London | 2026 |
| Aether Trees Limited | London | 2021 |
| AF Agri Ltd | Hull | 2020 |
| AF Farm Services Limited | Dungannon | 2010 |
| AF Farms Ltd | Dromore | 2021 |
| AF Fishing Ltd | Sheerness | 2022 |
| Affa International Limited | London | 2017 |
| Affini-Tree Limited | Cardiff | 2018 |
| Affinity Woodland Workers Co-Operative Ltd | Newton Abbot | 2000 |
| Affordable Equine Limited | Stoke-On-Trent | 2021 |
| Affordable Gardening Limited | Peterborough | 2006 |
| Affordable Tree Services Ltd | Loughborough | 2011 |
| Afforsk Enterprises Limited | Inverurie | 1999 |
| Afin Farming Ltd | Solihull | 2022 |
| AFK Farming Ltd | Hurlford | 2026 |
| AFK Services Limited | Newry | 2019 |
| AFN Groundworks Limited | St Helens | 2019 |
| Afraiscolte Ltd | London | 2019 |
| Afralink Solutions Ltd | Ellon | 2026 |
| Afram Vale Ltd | Derby | 2026 |
| Afri-Cann Limited | London | 2019 |
| Afri-Women Circle CIC | Derby | 2025 |
| Afribiz Management and Technology Ltd | London | 2020 |
| Africa Access Water UK Ltd | Edinburgh | 2026 |
| Africa's Gift Limited | Rotherham | 2012 |
| African Agronomix Limited | London | 2016 |
| African Forum Scotland Ltd | Edinburgh | 2019 |
| African Innovation and Development Centre CIC | Gravesend | 2019 |
| African Lakes Philanthropy Ltd | St. Andrews | 2005 |
| African Missions Northern Ireland Limited | Jerretspass | 1997 |
| African Speciality Products Limited | Newcastle | 2000 |
| African Sun Namibia Ltd | Epsom | 2023 |
| African Sun SA Ltd | Epsom | 2023 |
| Afrikan HUT PTY Ltd | London | 2024 |
| Afriqua Limited | Peterborough | 2026 |
| Afrocarbon Solutions Ltd | London | 2026 |
| Afroganic C.I.C. | Manchester | 2025 |
| Afroglobal Trade Ltd | London | 2017 |
| Afrorganic Ltd | London | 2018 |
| AFS (African Forum Scotland) Global Ltd | Edinburgh | 2020 |
| AFS Contractors Limited | Grantham | 2015 |
| AFS Seed Processing Ltd | Berwick Upon Tweed | 2015 |
| AFT Equine Ltd | Rugby | 2025 |
| Afton Meadow Limited | London | 2016 |
| Afton Park Limited | Freshwater | 2005 |
| Afton Projects Limited | Leeds | 2008 |
| AG & E Consultancy Services Ltd | Babraham | 2008 |
| AG Agri Ltd | Cheltenham | 2018 |
| AG DJ Brown Forestry Contractors Limited | Thetford | 2023 |
| AG Escargot Limited | Bognor Regis | 2018 |
| AG Farming Limited | Staffordshire | 2006 |
| AG Fences and Gates Ltd | East Grinstead | 2025 |
| AG Hera Associates Ltd | Faringdon | 2026 |
| AG Kennels Ltd | Aberdeen | 2026 |
| AG Kirkland Developments Ltd | Lancaster | 2019 |