| Trifecta Pest Solutions Limited | Reading | 2023 |
| Triffitt Nurseries Limited | Scarborough | 2003 |
| Trifolium Partnership Limited | Milton Keynes | 2020 |
| Trigger Direct Limited | Horsham | 2000 |
| Trigger N Trout Ltd | Dunoon | 2024 |
| Triggr Ltd | Preston | 2015 |
| Trigon Farm Ltd | Holsworthy | 2020 |
| Trilloes Tree Care Limited | Hereford | 2018 |
| Trilogy Sports Horses Ltd | Oakham | 2018 |
| Trim & Proper Tree Surgeons Ltd | Northampton | 2025 |
| Trimar Stud Ltd | Seascale | 2025 |
| Trimara Services UK Limited | Glasgow | 2016 |
| Trimble Farms Ltd | Kircubbin | 2022 |
| Trimmers Livery Limited | Hook | 2016 |
| Trims Fuels Ltd | Woodstock | 2024 |
| Trinafour Fold Holding Ltd | Edinburgh | 2020 |
| Trinder House Investments Limited | Southampton | 2005 |
| Trinidad Investments (U.K.) Limited | London | 2001 |
| Trinity Farm (Nottingham) Limited | Nottingham | 2023 |
| Trinity Farm Seagry Limited | Taunton | 2005 |
| Trinity Farrier Services Ltd | Norwich | 2018 |
| Trinity Holdings Eire Limited | Newry | 2019 |
| Trinity Land Limited | Northampton | 1994 |
| Trinity Park Stud Ltd | Hungerford | 2013 |
| Trinity Quail UK Limited | Marehay | 2023 |
| Trinity Tree Solutions Ltd | Cambridge | 2020 |
| Trink Dairy Limited | Truro | 2010 |
| Triple a Concept Ltd | Birmingham | 2025 |
| Triple a Fishing Ltd | Banchory | 2024 |
| Triple Aces (Pugs & Bullys) Ltd | Basildon | 2018 |
| Triple HHH Ltd | London | 2021 |
| Trisant Design Solutions Ltd | Anglesey | 2025 |
| Triscombe Estate Ltd | Taunton | 2022 |
| Trish Global Company Limited | Bedford | 2026 |
| Tristan Kinnear Limited | Antrim | 2011 |
| Triton Farms Limited | London | 2025 |
| Triton Renewable Solutions Limited | London | 2024 |
| Triton Seed Drills Ltd | Cambridge | 2017 |
| Triumph Trawling Ltd | Eyemouth | 2021 |
| Triverdant PVT Ltd | Hereford | 2025 |
| Trixpixmedia Ltd | Dumfries | 2011 |
| TRJ Fishing Ltd | Dingwall | 2012 |
| TRN Contracts Ltd | Ederney | 2014 |
| Troed Y Foel Livestock Ltd | Tywyn | 2020 |
| Troed-Y-Rhiw Horse Training Limited | Pontypridd | 2021 |
| Trojan Equine Limited | Carmarthen | 2002 |
| Trojan Horse Shavings & Animal Beddings Ltd | Leigh | 2026 |
| Tropaquatics Ltd | Newport | 2026 |
| Tropic Biosciences UK Limited | Norwich | 2016 |
| Tropic City Limited | Exeter | 2023 |
| Tropic Supply UK Limited | Norwich | 2026 |
| Tropical Bites Fruits Ltd | London | 2026 |
| Tropical Britain Limited | Twickenham | 2011 |
| Tropical Environmental Consultants Limited | Blackpool | 2019 |
| Tropical Forest Plantations Limited | Leigh-On-Sea | 2014 |
| Tropical Marine Aberdeen Ltd | Aberdeen | 2019 |
| Tropical Marine Centre (2012) Ltd | Chorleywood | 2012 |
| Tropical Marine Centre Limited | Chorleywood | 2009 |
| Tropical Pastures Biotech Ltd | London | 2019 |
| Tropicroot Hydroponics Ltd | Craigavon | 2026 |
| Tropos Drone Services Ltd | Carmarthen | 2025 |
| Troserch Woodland (Property) Limited | Llanelli | 2006 |
| Troston Farms Limited | Bury St. Edmunds | 1961 |
| Trot Together Ltd | Woking | 2025 |
| Trotside Limited | Oakley | 1977 |
| Trotter Contracts Limited | Dungannon | 2015 |
| Troutflies UK Ltd | Morecambe | 2012 |
| Trouw (UK) Pension Trust Limited | Ashbourne | 1994 |
| Trowbridge Farming Ltd | Taunton | 2021 |
| Troy Ltd | Devon | 2005 |
| Troyal Farms Limited | Newark | 2012 |
| TRS Tree Management Ltd | Glasgow | 2023 |
| TRU LI Tree Services Ltd | Uxbridge | 2015 |
| Trucketts Hall Farm Boxted Limited | Cambridge | 1978 |
| True Harvest Seeds | Downpatrick | 2013 |
| True North Equine Limited T/A the Cornmill Farm & Stud Limited | London | 2010 |
| True Summit Arborists Limited | Petersfield | 2025 |
| Truemans Heath Farm Ltd | Birmingham | 2023 |
| Truesdale Paddock & Grassland Ltd | Newry | 2025 |
| Truestar Services Limited | Nottingham | 1991 |
| Truewood Ltd | Derby | 2026 |
| Truffiere Limited | Croydon | 2018 |
| Truffle Farms Europe Limited | Edinburgh | 2015 |
| Truffle PIG Farming Limited | Sherborne | 2025 |
| Truffle Sales Ltd | London | 2012 |
| Truffle Trees Direct Limited | Louth | 2023 |
| Trufflemen Ltd | Dunstable | 2022 |
| Truffles and BIO Products Ltd | Enfield | 2021 |
| Truleaf Farm Ltd | Banbury | 2019 |
| Trumper Tree Care Limited | Banstead | 2024 |
| Trumpet Gold UK Ltd | Weymouth | 2024 |
| Trumpington Enterprises Limited | Cambridge | 1986 |
| Trumpington Farm Company, Limited | Cambridge | 1957 |
| Trunce Farm Limited | Sheffield | 2021 |
| Trunks Tree Care Ltd | Leyland | 2018 |
| Truro Market Auctioneers Limited | Cornwall | 1973 |
| Truscope Utility ARB Ltd | Crawley | 2025 |
| Trusler's Hill Farms Limited | Henfield | 1923 |
| Truslers Hill Estate Limited | Hassocks | 2023 |
| Trust Farm Ltd | Woodbridge | 2007 |