| U.K. Hardwoods Limited | South Molton | 1999 |
| U.K. Nexus Educational Consultancy Limited | Bristol | 2024 |
| U.K. Supercarp Limited | Poulton Le Fylde | 2008 |
| U.M.E (NI) Ltd | Craigavon | 2003 |
| UB Farm Limited | Alton | 2024 |
| Ubhal-Ghort Beag AIG Fearnan Ltd | Aberfeldy | 2025 |
| UCC Worldwide Ltd | Sheffield | 2020 |
| Uchaf Fields Ltd | Chesham | 2014 |
| Uchchaihshravas Thoroughbreds Limited | London | 2024 |
| Udallsfield Allotment Association Limited | Stoke-On-Trent | 2015 |
| Udgam Service Solutions Ltd | London | 2023 |
| UEM Consultants Ltd | London | 2020 |
| Ufarms.Io Ltd | Glasgow | 2023 |
| Uffington Equestrian Limited | Stamford | 2021 |
| Ufkes Greentec UK Limited | Driffield | 2018 |
| Ufton Green Stables Ltd | Wokingham | 2024 |
| Ugie Farms Limited | Peterhead | 2021 |
| UGL Ltd | Kendal | 2007 |
| UH Trader Hub Ltd | Aberdeen | 2026 |
| UIG Bay Artisan Croft Ltd | Timsgarry | 2017 |
| UIG Seafare Limited | Isle Of Lewis | 2004 |
| Uigshader Living Forest Project Limited | Portree | 2018 |
| Uist Honey Bees Ltd | Isle Of North Uist | 2025 |
| UJ2 Consultants Ltd | Glasgow | 2019 |
| Ujamaflip Limited | Malmesbury | 2017 |
| UK 777 Ltd | Worcester | 2022 |
| UK Ageluo Morgan Huaxue Ltd | Stafford | 2024 |
| UK Agility Limited | Evesham | 2004 |
| UK Agri-Tech Centre Limited | York | 2023 |
| UK Agricultural Hemp Ltd | London | 2019 |
| UK Agriculture Group Co., Ltd | London | 2026 |
| UK Amenity Limited | Huntingdon | 2009 |
| UK Aquaculture Ltd | Macclesfield | 2025 |
| UK Asta Chemicals Group Ltd | West Midlands, England | 2024 |
| UK Avatar Giant Stone AS Energy Mining Co., Ltd | Beckenham | 2023 |
| UK Bait Company Limited | Upminster | 2017 |
| UK Biosmart Technologies Ltd | Dudley | 2020 |
| UK Black Cat Ltd | Carlisle | 2011 |
| UK Carbon Capture Ltd | Llansantffraid | 2020 |
| UK Carp Promotions Ltd | Dudley | 2024 |
| UK Christmas Trees Limited | Wantage | 2006 |
| UK Coral Farm Limited | Chelmsford | 2015 |
| UK Country Estates Limited | Winchester | 2012 |
| UK Custom Aquascapes Ltd | Basingstoke | 2025 |
| UK Dedicated Animal Carers & Trainers Ltd | London | 2025 |
| UK Deer Services Ltd | Hope Valley | 2025 |
| UK Deer Stalking Limited | Whitstable | 2015 |
| UK Domya Agricultural International Limited | Manchester | 2025 |
| UK Dressage Ltd | Milton Keynes | 2024 |
| UK Elite Assistance Dogs Limited | Wigan | 2025 |
| UK Essential Oils Ltd | St Helens | 2011 |
| UK Farming, Forestry and Aquaculture Ltd | Selby | 2015 |
| UK Firewood Processing Ltd | Pwllheli | 2022 |
| UK Forrest International Chemical Group Limited | Cambridge | 2023 |
| UK Fresh RM Ltd | Hoddesdon | 2024 |
| UK Fruit Ltd | Oban | 2025 |
| UK Gofflow International Chemical Ltd | Cardiff | 2021 |
| UK Hanoverians Limited | Bristol | 2001 |
| UK Harbours Limited | Dover | 2024 |
| UK Herbex Ltd | Bedford | 2024 |
| UK Hide and Skins Ltd | Kidderminster | 2022 |
| UK Honey Ltd | Ossett | 2023 |
| UK Huang JIA Biotechnology Ltd | Cardiff | 2025 |
| UK K9 R&C Division Ltd | Manchester | 2025 |
| UK KOI Imports Ltd | Newcastle | 2025 |
| UK Lihao International Investment and Development Company Limited | Manchester | 2024 |
| UK LOG Exports Ltd | London | 2015 |
| UK Lusimai Seaweed Technology Ltd | London | 2024 |
| UK Muhe Co., Ltd | Cardiff | 2022 |
| UK Nature Projects Association Limited | Edinburgh | 2025 |
| UK Novory Co, Limited | Kington | 2026 |
| UK Petnutro International Group Limited | West Midlands, England | 2025 |
| UK Pets Gogo Supplies Ltd | Stockport | 2014 |
| UK Puls Chemical Company Ltd | Manchester | 2021 |
| UK Pulses Ltd | Cambridge | 2016 |
| UK Putange Supplies Ltd | Tain | 2025 |
| UK Pythons Limited | Liverpool | 2021 |
| UK Reindeer Herders Association Limited | Seaham | 2017 |
| UK Roman Ltd | Haverfordwest | 2026 |
| UK SAN York Mining Co., Ltd | Gillingham | 2025 |
| UK Scallops Limited | Shetland | 2001 |
| UK Seaweed Ltd | Peterborough | 2025 |
| UK Shiruiqi Biotechnology Co., Ltd | Cambridge | 2022 |
| UK Sire Services Limited | Totnes | 2001 |
| UK Sport Horses Limited | Salford | 2010 |
| UK Sporting and Management Ltd | Market Rasen | 2024 |
| UK Treework Limited | Leicester | 2004 |
| UK Vine Care Limited | Worthing | 2014 |
| UK Watercourse & Fisheries Ltd | Braintree | 2026 |
| UK Waxworms Limited | Sheffield | 2010 |
| UK Woodland Limited | Woodbridge | 2013 |
| UK XH Limited | Cardiff | 2022 |
| UK YZ Agrotech Corp Limited | Gillingham | 2025 |
| UK Zhongnong Marine Life Limited | West Midlands, England | 2026 |
| Uk-Africa Innovation Hub CIC | Manchester | 2025 |
| Ukbiochar Ltd | Pencombe | 2018 |
| Ukca Limited | Battle | 2004 |
| Ukep Association Limited | Bridgwater | 1977 |
| Ukko Organics Limited | Cirencester | 2019 |
| Ukme Services Ltd | Tarporley | 2020 |