| Annona AG Limited | Bourne | 2015 |
| Anns Hill Farm | Cockermouth | 2009 |
| Annyalla Chicks (UK) Broiler Breeders Limited | Wrexham | 2015 |
| Annyalla Chicks (UK) Broilers Limited | Wrexham | 2015 |
| Annyalla Chicks (UK) Limited | Wrexham | 2010 |
| Another Nice View Ltd | Addlestone | 2025 |
| Ansdell Farms Limited | Barnstaple | 2008 |
| Anside Pedigree Livestock Ltd | Huntly | 2012 |
| Anson Game & Forestry Ltd | Winchester | 2026 |
| Anstee Services Ltd | Leicester | 2016 |
| Anstey Goldsack Ltd | Hereford | 2025 |
| Ansteys of Worcester Limited | Worcester | 2014 |
| Anstruther Holding Ltd | Ruislip, | 2026 |
| Ant's Plants Ltd | London | 2024 |
| Antares Fishing (Whalsay) Company Limited | Lerwick | 1988 |
| Antas Limited | Cambridge | 1995 |
| Antell Brothers Limited | Wimborne | 1955 |
| Anthony Agricultural Services Limited | Stockport | 2016 |
| Anthony Dawson Limited | Coleby | 1984 |
| Anthony Falconry Limited | London | 2001 |
| Anthony Hartley Ltd | Broughton In Furness | 2007 |
| Anthony Hewson Tree Services Limited | Birmingham | 2025 |
| Anthony Phillips Consulting Limited | Galashiels | 2025 |
| Anthony Seaman & Sons Limited | Norwich | 1954 |
| Antoni Handyman Ltd | Carmarthen | 2017 |
| Antonia B Service Limited | Bedford | 2025 |
| Antony Charles Treescapes Limited | Walsall | 2011 |
| Antony Price Limited | Lancashire | 2003 |
| Antony Rose Ltd | London | 2021 |
| Antrim Quality Lamb Ltd | Carrickfergus | 2000 |
| Antrobus Farm Limited | Yorks | 1955 |
| Antspire Limited | Thetford | 1997 |
| Antur Cymuned Brithdir Mawr Cyfyngedig | Sir Benfro | 2004 |
| Anupro Ltd | Omagh | 2020 |
| Anve Honey Ltd | Hereford | 2023 |
| Anvil Alpacas Ltd | Durham | 2025 |
| Anvil Engineering Limited | Newcastle | 2014 |
| ANY One Enterprises Limited | Petworth | 2011 |
| Anywayed Ltd | London | 2017 |
| Anywin Co., Limited | Beckenham | 2007 |
| Aohh Ltd | Sheffield | 2021 |
| AOS Industries Ltd | Warrington | 2026 |
| AP Agri Limited | Coylton | 2011 |
| AP Agri Services Limited | Thornton Cleveleys | 2025 |
| AP Agricultural Contractors Limited | Highbridge | 2026 |
| AP Farm Solutions Limited | Market Rasen | 2024 |
| AP Forestry Ltd | Hereford | 2023 |
| AP Tree Specialists Ltd | Derby | 2004 |
| AP Trees (Kent) Limited | Rochester | 2017 |
| APA Management Ltd | Derby | 2023 |
| Apache Forestry and Arboriculture Limited | Cosham | 2017 |
| Apax Corals Ltd | Oxfordshire | 2025 |
| APB Farms Limited | Dungannon | 2024 |
| APB Forestry Ltd | Bordon | 2020 |
| Apbees Ltd | Brigg | 2026 |
| APE Ranch Ltd | Penarth | 2025 |
| APE Tree Services Ltd | Richmond | 2025 |
| Apeel Sciences UK Limited | London | 2020 |
| Apest Control Limited | Saundersfoot | 2002 |
| Apex Apiaries Ltd | Nottingham | 2024 |
| Apex Caelestis Ltd. | Manchester | 2015 |
| Apex Environmental Limited | Lichfield | 2013 |
| Apex Forestry Ltd | Walkerburn | 2018 |
| Apex Genetics Ltd | Ballymena | 2025 |
| Apex Green Horticultural Design Studio Limited | Sheffield | 2021 |
| Apex International Trade Ltd | London | 2024 |
| Apex K9 Ltd | Gillingham | 2024 |
| Apex Land Investment Limited | Northamptonshire | 2004 |
| Apex Soil Solutions Limited | Christchurch | 2018 |
| Apex Trade Solutions Ltd | Rainham | 2023 |
| Apex Tree Surgeons Limited | Christchurch | 2012 |
| Apex Trees Ltd | Inverness | 2025 |
| Apex Woodland & Wildlife Services Ltd | Polegate | 2023 |
| Apexequine Ltd | Holsworthy | 2026 |
| APF International Forest Machinery Exhibition Ltd. | Edinburgh | 2002 |
| Aphrodite Pet Services Limited | Chigwell | 2026 |
| Apiarist GPC Ltd | Haslemere | 2025 |
| Apiary by Bell Ltd | Brighton | 2021 |
| Apiary Ltd | Basingstoke | 2025 |
| Apicalarb Tree Services Ltd | Hemel Hempstead | 2022 |
| Apisterra Limited | Goole | 2026 |
| Apix Nutrition Limited | Gateshead | 2018 |
| APJ Dairies Limited | Bromsgrove | 2018 |
| APL Agri Xtra Ltd | Thirsk | 2020 |
| Apline Kennels & Equestrian Ltd | Monmouth | 2022 |
| Aplins Farms Limited | Taunton | 2020 |
| Aplus Pestcontrol & Drain Solutions Limited | Chepstow | 2025 |
| Apna Punjab Farm Ltd | Kidderminster | 2025 |
| Apol Silva & Orchards Limited | London | 1995 |
| Apollo Animal Physiotherapy Ltd | Margate | 2024 |
| Apollo Farms Limited | Bury St. Edmunds | 2002 |
| Apollo Marine Systems Ltd | Weymouth | 2014 |
| Aponic International Ltd | Sudbury | 2017 |
| Aponic Ltd | Sudbury | 2014 |
| Appin Forest Services C.I.C. | Appin | 2026 |
| Apple Blossom Social Enterprise CIC | Builth Wells | 2022 |
| Apple Dexters Ltd | Bordon | 2023 |
| Apple Innovation Ltd | London | 2020 |
| Apple Orcharding Solutions Limited | Hereford | 2010 |
| Apple Tree Farm Ltd | Lisburn | 2016 |