| TRB LIMITED | ST. ASAPH | A rating |
| Treasure Data (UK) Limited | London | A rating |
| Treasury Wine Estates EMEA Limited | Twickenham | A rating |
| Treatwell Limited | London | A rating |
| Tredence UK Limited | London | A rating |
| Treis Partners Advisory Limited | London | A rating |
| Trek Bicycle Corporation | Milton Keynes | A rating |
| Treliant Limited | Belfast | A rating |
| Trelleborg Sealing Solutions UK Ltd | Tewkesbury | A rating |
| Trend Micro (UK) Limited | London | A rating |
| Trendstream Limited | London | A rating |
| Trenitalia UK Limited | London | A rating |
| TRESATA LTD | KINGSTON UPON THAMES | A rating |
| Trescal Limited | Yateley | A rating |
| Tresmares Capital UK Limited | London | A rating |
| Tresmares Direct Lending UK | London | A rating |
| TresVista UK Ltd | London | A rating |
| TRG Arts Limited | London | A rating |
| Tri-Wall UK Limited | Monmouth | A rating |
| Trianz Digital Ltd | Beckenham | A rating |
| Trianz Limited | Beckenham | A rating |
| Tribal Group Plc | Sheffield | A rating |
| Tribe Group Digital Limited | London | A rating |
| Tribe Infrastructure (UK) Ltd | London | A rating |
| Tricentis UK Limited | London | A rating |
| Tricon Infotech UK Limited | Reading | A rating |
| TRIDENT ENERGY MANAGEMENT LIMITED | LONDON | A rating |
| Tridonic Uk Limited | Spennymoor | A rating |
| Trigo Vision UK Ltd | London | A rating |
| TRILLIANT NETWORKS (UK) LTD | Windsor | A rating |
| Trillium Flow Technologies Holdco Limited | London | A rating |
| Trimble R&D UK Limited | Morley | A rating |
| TRINA SOLAR UK HOLDCO LTD | London | A rating |
| Trinitarian Bible Society | London | A rating |
| Trinity Investments Europe Limited | London | A rating |
| Trinity Life Sciences UK Limited | London | A rating |
| Trintech (UK) Limited | London | A rating |
| Trio Motion Technology Limited | Tewkesbury | A rating |
| Triodos Bank UK Ltd | Bristol | A rating |
| Triogen Ltd | Glasgow | A rating |
| Trip Air Ticketing (UK) Limited | London | A rating |
| TripAdvisor Ltd | London | A rating |
| Triple Line Consulting Limited | London | A rating |
| TripleLift UK Ltd | Surrey | A rating |
| Triptease Limited | London | A rating |
| Tripwire International, Inc. | Maidenhead | A rating |
| TriSpan LLP | London | A rating |
| Tristel Solutions Limited | Snailwell | A rating |
| Tritech Precision Products Limited | Wrexham | A rating |
| Triton Container UK Limited | London | A rating |
| Triumph Motorcycles Limited | Hinckley | A rating |
| Trive Financial Services UK Limited | London | A rating |
| TRNC LONDON REPRESENTATIVE OFFICE | LONDON | A rating |
| Tronox Pigment UK Limited | London | A rating |
| Tropicana Products UK Ltd | Reading | A rating |
| Trouw UK Ltd t/a Trouw Nutrition | Ashbourne | A rating |
| Trowbridge International Tax Services Ltd | London | A rating |
| Truck-lite Europe Ltd | Harlow | A rating |
| Tructyre Fleet Management Limited | Gateshead | A rating |
| True Europe LLP | London | A rating |
| True Refrigeration UK Limited | Rotherham | A rating |
| True World Foods (UK) Ltd | Southall | A rating |
| TrueCommerce (Coventry) Limited | Manchester | A rating |
| Trumid Financial UK Limited | London | A rating |
| Trust Payments Limited | London | A rating |
| TrustCloud Ltd | London | A rating |
| TrustCSR Ltd | Tetbury | A rating |
| Trustly UK Limited | London | A rating |
| Trustpilot Ltd | London | A rating |
| Trutex Ltd | Clitheroe | A rating |
| Truth Consulting | London | A rating |
| Tryg Forsikring A/S | London | A rating |
| Tryzens Limited | London | A rating |
| TS Imagine (UK) Ltd | London | A rating |
| TSA Riley Limited | London | A rating |
| TSK ELECTRONICA Y ELECTRICIDAD UK LIMITED | London | A rating |
| TSO SAS UK | London | A rating |
| Tsubakimoto UK Ltd | Annesley | A rating |
| TT Games Limited | Knutsford | A rating |
| TT International Investment Management LLP | London | A rating |
| TTB Partners Investment Advisory Ltd | London | A rating |
| TTEC UK Solutions Limited | Belfast | A rating |
| TTP Group Limited | Royston | A rating |
| Tube Tech Industrial Limited | Canvey Island | A rating |
| TUBI Media Group Ltd | London | A rating |
| Tubular Labs UK Limited | London | A rating |
| Tudor Capital Europe LLP | London | A rating |
| Tufin Software Europe Limited | Reading | A rating |
| TUI Travel Limited | Luton | A rating |
| Tulcan Energy Resources UK | London | A rating |
| Tullow Oil Plc | London | A rating |
| TULU TECH LTD | London | A rating |
| Tun Abdul Razak Research Centre | Hertford | A rating |
| Tungsten Automation UK Limited | London | A rating |
| Tunisair | London | A rating |
| Tunstall Healthcare (UK) Limited | Whitley | A rating |
| Tupras Trading Ltd | London | A rating |
| Turbine Simulated Cell Technologies Limited | Cambridge | A rating |
| Turbo Power Systems | Gateshead | A rating |
| Turkish Airlines Inc | London | A rating |
| Turkish Bank (UK) Ltd | London | A rating |
| Turkiye Is Bankasi A.S. | London | A rating |
| Turner & Townsend Ltd | Leeds | A rating |
| Turner Broadcasting System Europe Limited | London | A rating |
| Turnitin UK LTD | Newcastle Upon Tyne | A rating |
| Turnstile Group Limited | London | A rating |
| TuroUK Ltd | London | A rating |
| Turtle Wax Europe Limited | Liverpool | A rating |
| Tuspark Holdings (UK) Limited | Cambridge | A rating |
| Tutors International Ltd | Oxford | A rating |
| TUV Rheinland UK Ltd | Shirley | A rating |
| TUV SUD Limited | Fareham | A rating |
| TV Asahi London Bureau | London | A rating |
| TV Tokyo Corporation London Bureau | London | A rating |
| TVS Motor Company Limited UK Branch | Kenilworth | A rating |
| TVS SCS IFM LIMITED | Chorley | A rating |
| TVS Supply Chain Solutions | Chorley | A rating |
| TVSquared Ltd. | Edinburgh | A rating |
| TWG CADILLAC FORMULA 1 TEAM LIMITED | Silverstone | A rating |
| TWI Ltd | Cambridge | A rating |
| Twilio UK Limited | London | A rating |
| Two Circles Limited | London | A rating |
| Two Sigma International Limited | London | A rating |
| TWP INTERNATIONAL LLC | Harrogate | A rating |
| TXO Systems Ltd | Chepstow | A rating |
| TXOdds (UK) Limited | London | A rating |
| TXT Next Limited | Stockton-on-Tees | A rating |
| Tyco Electronics UK Ltd | Swindon | A rating |
| TYK Limited | Chilton | A rating |
| Tymphany Acoustic Technology (UK) Limited | Bridgend | A rating |
| Typeform UK Limited | London | A rating |
| TYPSA Limited | London | A rating |
| Tysers Insurance Brokers Ltd | London | A rating |
| Tyson Foods Products Limited | Ashford | A rating |
| U.S. Bank Europe DAC | London | A rating |
| Uart Studio Limited | London | A rating |
| UAV Tactical Systems Limited | Leicester | A rating |
| Uber Eats UK Limited | London | A rating |
| Uber London Limited | London | A rating |
| Uberbinder Limited | Oxford | A rating |
| UBIQUE SYSTEMS UK LIMITED | LONDON | A rating |
| Ubiquiti Distribution UK Limited | London | A rating |
| Ubisoft Reflections Ltd | Gosforth | A rating |
| UBS AG | London | A rating |
| UCB S.A. and UCB Celltech | Slough | A rating |
| UCC Europe Limited | Ealing | A rating |
| Uchimura UK. Ltd | Co. Durham | A rating |
| ucreate Limited | London | A rating |
| Uflex Europe Limited | London | A rating |
| Uhlmann U.K. Limited | Sandhurst | A rating |
| UK Bandwidth Limited | London | A rating |
| UK Branch of EnterpriseJungle, Inc t/a EnterpriseAlumni | London | A rating |
| UK Branch of Sewon Chemical Co., LTD | London | A rating |
| UK COLLEGE OF BUSINESS AND COMPUTING LTD | London | A rating |
| UK ESTABLISHMENT OF PENTAIR PUBLIC LIMITED COMPANY | Twickenham | A rating |
| UK Fan Tuan Ltd | London | A rating |
| UK GLOBAL COMMODITIES LIMITED | London | A rating |
| UK Greetings Ltd | Dewsbury | A rating |
| UK LIVING CONDITIONS LTD | London | A rating |
| UK MONTEIRO LTD | Bristol | A rating |
| UK NetEase Interactive Entertainment Limited | Guildford | A rating |
| UK NSI Co Ltd | Worcestershire | A rating |
| UK Property Accountants Ltd | London | A rating |
| UK UNCOUNTABLE LIMITED | Cheltenham | A rating |
| UK-China Culture & Education Cooperation Promotion Centre Ltd | Oxford | A rating |
| UKFH Limited | London | A rating |
| UKForex Limited | London | A rating |
| UKG Technology Limited | Bracknell | A rating |
| Ukheshe International Ltd | London | A rating |
| UL International (UK) Ltd | Basingstoke | A rating |
| UL VS Limited | Basingstoke | A rating |
| ULC Robotics International, LTD | Feltham | A rating |
| Ultimate Products UK Ltd | Chadderton | A rating |
| Ultra Electronics Holdings Limited | London | A rating |
| Ultralytics Ltd | London | A rating |
| Ultrapolymers Ltd | Thelwall | A rating |
| UMEDA ARTS THEATRE UK LIMITED | London | A rating |
| Umicore Marketing Services UK Ltd | Hertford | A rating |
| Unatrac Limited | Slough | A rating |
| Underwater Construction Corporation UK Ltd | Cumbria | A rating |
| Unico UK Ltd | Milton Keynes | A rating |
| Unicredit Bank GMBH London Branch | London | A rating |
| Unifrax UK Limited | St. Helens | A rating |
| Unilever UK Limited | Kingston-upon-Thames | A rating |
| Unilin Distribution Ltd. | Newry | A rating |
| Unilin Insulation UK Ltd. | Chesterfield | A rating |
| Unimetals Services Limited | London | A rating |
| UNION BANCAIRE PRIVEE | LONDON | A rating |
| Union Bancaire Privee (UK) Limited | London | A rating |
| UNION BANK OF INDIA (UK) LIMITED | London | A rating |
| UnionPay International Co., Ltd UK Branch | London | A rating |
| UNIPART GROUP LIMITED | COWLEY | A rating |
| Unipec Singapore Pte. Ltd | London | A rating |
| Unipec UK Company Limited | London | A rating |
| Uniper UK Ltd | Solihull | A rating |
| UNIPRES (UK) LIMITED | Sunderland | A rating |
| UNIQLO EUROPE LTD | London | A rating |
| UNIQUE AIR EXPRESS LIMITED | feltham | A rating |
| Unispace Global Limited | London | A rating |
| Unisys Limited | MILTON KEYNES | A rating |