| UK Ward Agricultural Group Co., Ltd | Cambridge | 2026 |
| UK West DAN Agricultural International Group Chemical Ltd | Cardiff | 2021 |
| UK Woreison Chemical Co., Ltd | Cardiff | 2026 |
| UK Wotaisen Chemical Co., Ltd | Beckenham | 2024 |
| UK Yamon (International) Crop Nutrition Limited | Coventry | 2025 |
| UK Yingrui International Agriculture Co., Limited | Beckenham | 2021 |
| UK Youdid Crop Nutrition Ltd | Cambridge | 2021 |
| UK Zell Chemical (Europe) Industries Ltd | Coventry | 2025 |
| Uk.Borlingham Chemical Industry Limited | London | 2024 |
| Ukog (137/246) Ltd | London | 2009 |
| Ukog (234) Ltd | London | 2009 |
| Ukog (GB) Limited | Newark | 2000 |
| Ukog Turkey Ltd | London | 2016 |
| Ukraine Critical Minerals Limited | Ashford | 2022 |
| Ukxenergy Limited | Bury St Edmunds | 2019 |
| Ulster Crop Nutrition, Northern IE Co., Ltd | Coventry | 2026 |
| Ultramar Energy Ltd | Cardiff | 2018 |
| Ultramarine Consulting Limited | Darlington | 2009 |
| Umbilical Management Services Ltd | Newcastle Upon Tyne | 2012 |
| UMD Energy Limited | London | 2023 |
| Unco Global Asset Management Agency Ltd | Farnham | 2010 |
| Unconventional E&P Services Limited | Malvern | 2014 |
| Underwater Consultancy Services Ltd | Norwich | 2007 |
| Underwater Project Management Limited | Banchory | 2023 |
| Uniconn (Scotland) Limited | Aberdeen | 2018 |
| Unicorn Crop Nutrition Co., Ltd. | Kingston Upon Thames | 2020 |
| Unidaco Ltd | London | 2015 |
| Unimarket Limited | Birmingham | 2006 |
| Union Jack OIL PLC | Bath | 2011 |
| United Crushers Ltd | London | 2021 |
| United Downs Lithium Limited | Redruth | 2022 |
| United Mining Services Construction Limited | Altrincham | 2024 |
| United Mining Services Limited | Altrincham | 2015 |
| United OIL & GAS PLC | London | 2015 |
| United Rentals UK Limited | Brigg | 2012 |
| United Rotating UK Ltd | Exeter | 2023 |
| Universal Coal Limited | London | 2002 |
| Universal Crypto Ltd | Hornchurch | 2018 |
| Universal Exports 2021 Ltd | London | 2015 |
| Universal Future Capital Mining Limited | London | 2025 |
| Universal Glass Ltd | Sheffield | 2023 |
| Universal Pozzolanic Silica Alumina Ltd | London | 2023 |
| Upstream Concept Engineering Ltd | West Byfleet | 2014 |
| Upstream Solutions Limited | London | 2007 |
| Upstream Tubulars Ltd | Basildon | 2010 |
| Uptime Corrosion & Materials Consultants Limited | Aberdeen | 2014 |
| Uramerica Limited | London | 2007 |
| URU Metals Ltd | London | 2017 |
| Uruk Holding Group for Automotive Industry, Petroleum, Energy and Investments Limited | London | 2024 |
| US Comanzhuo Shares Co., Ltd | Cambridge | 2025 |
| USA Sedin Chemical Group Co., Ltd | West Midlands, England | 2026 |
| UVI Digger Ltd | Romford | 2025 |
| Uzella Marine Limited | Lostwithiel | 2004 |
| Uzimele Consulting Ltd | Purley | 2008 |
| V J Milman Tippers Ltd | Hornchurch | 2025 |
| V P Drilling Limited | Great Yarmouth | 2024 |
| Valaris PLC | Brighton | 2009 |
| Vale Base Metals Limited | London | 2023 |
| Valero Express Limited | London | 2025 |
| Valerom Associates Ltd | Edinburgh | 2014 |
| Valhalla OIL and GAS Limited | London | 2005 |
| Valley Stone Limited | Stoke On Trent | 2003 |
| Valloney Limited | London | 2017 |
| Valor Global Energy Ltd | London | 2018 |
| Valor Salt Extraction Ltd | Liversedge | 2021 |
| Value Addition Ltd | Broxbourne | 2025 |
| Value Flooring Ltd | Great Yarmouth | 2019 |
| Valve Resources & Solutions Limited | Edinburgh | 2012 |
| Vampire Production Limited | Aberdeen | 2013 |
| Vandelay Industries Management Ltd | London | 2020 |
| Vanguard Energy Group Limited | Bradford | 2015 |
| Vanguard OIL & GAS Ltd | Blackpool | 2023 |
| Vangunn Limited | Guildford | 2012 |
| Vanta Mining Ltd | West Midlands, England | 2026 |
| Vardar Minerals Limited | London | 2016 |
| Varidrill Limited | Woodhall Spa | 2013 |
| Vasco Consulting Ltd | Wrexham | 2023 |
| Vatukoula Gold Mines Limited | London | 2004 |
| Vault Access Ltd | Blackpool | 2014 |
| Vault Digital Holding Group Limited | London | 2024 |
| Vayco OIL Tools Ltd | Norwich | 2016 |
| VC - Veritas Consultancy Ltd | London | 2025 |
| VDS Consultancy Limited | Dundee | 2018 |
| Vector Inspection Limited | Chester | 2019 |
| Vector Supplies Limited | Dyce | 1987 |
| Vedadri Ltd | Aberdeen | 2018 |
| Vedanta Resources Limited | London | 2003 |
| Vela Royalties Limited | London | 2022 |
| Venoil Limited | Wembley | 2024 |
| Ventastone Ltd | Great Dunmow | 2026 |
| Venus Minerals Limited | London | 2019 |
| Venus Offshore Ltd | Whitby | 2023 |
| VER Projects Ltd | St. Albans | 2018 |
| Verde Magnesium Ltd | London | 2025 |
| Veritas Mining Ltd | Harrow | 2017 |
| Versis Ltd | Aberdeen | 2022 |
| Vertas Services Limited | Ellon | 2018 |
| Vertex Services & Hire Ltd | Newtown St Boswells | 2026 |
| Vertical Blue Sky Ltd | Bangor | 2016 |
| Verto Hydrogen Ltd | Worthing | 2023 |