| Timalloy Limited | Hospitality | 1994 |
| Time Express Limited | Transport & logistics | 2024 |
| TIN and Copper Ltd | Information & communication | 2021 |
| TIN Coast Cheese Ltd | Wholesale & retail | 2025 |
| Tinker Taylor Management Company Limited | Hospitality | 2002 |
| Tinkture Ltd | Wholesale & retail | 2017 |
| Tiny Agency Marketing Ltd | Professional & scientific | 2019 |
| TJ Cornwall Limited | Construction | 2017 |
| TMC Cornwall Limited | Wholesale & retail | 2025 |
| Tmgs Properties Ltd | Real estate | 2017 |
| Toby Cape Plumbing and Heating Limited | Construction | 2012 |
| Tome Autos Ltd | Administrative & support | 2026 |
| Toms Electrical Contracting Services Limited | Manufacturing | 2010 |
| Tonkin and SON Limited | Construction | 2024 |
| Tony Baldwin Holdings Limited | Financial services | 2025 |
| TOR Currency Exchange Limited | Financial services | 2004 |
| Tough Dough CIC | Arts & recreation | 2015 |
| Tower Park Camping Limited | Hospitality | 2006 |
| Trading for Life Limited | Wholesale & retail | 2020 |
| Trans-Europe Software Services Limited | Information & communication | 2000 |
| Travellerspace | Education | 2012 |
| Tredd UK Ltd | Health & social care | 2021 |
| Treen Farm Campsite LLP | | 2021 |
| Tregear Architectural Services Ltd | Administrative & support | 2012 |
| Tregulver Limited | Real estate | 2018 |
| Trelawny Citroen Limited | Wholesale & retail | 2008 |
| Trelew House Management Limited | Households | 2022 |
| Trelew Management Company Limited | Real estate | 2008 |
| Trelya | Health & social care | 2001 |
| Tremayne Rural Retreats Ltd | Hospitality | 2023 |
| Tremellion Ltd | Hospitality | 2020 |
| Tremenheere Holdings Limited | Real estate | 2021 |
| Tremenheere Home Care Limited | Health & social care | 2017 |
| Tremenheere Trading Limited | Arts & recreation | 2000 |
| Tremethick Medico-Legal Reporting Ltd | Health & social care | 2012 |
| Treneer Limited | Real estate | 2003 |
| Trengwainton Developments Limited | Real estate | 1997 |
| Trengwainton Farms Limited | Real estate | 1997 |
| Trenoweth Construction Limited | Real estate | 1988 |
| Trenoweth Limited | Agriculture & fishing | 2018 |
| Trenowin Property Limited | Real estate | 2024 |
| Trenuggo Shires (Boswens) Limited | Agriculture & fishing | 2006 |
| Trereife Equestrian Ltd | Agriculture & fishing | 2017 |
| Trerubies Engineering Consulting Ltd | Professional & scientific | 2020 |
| Trevail Management Company Limited | Households | 2006 |
| Trevaskis Developments Ltd | Construction | 2018 |
| Trevaskis Investments Limited | Real estate | 2024 |
| Trevaylor Leisure Ltd | Hospitality | 2018 |
| Trevedra Farm Caravan & Camping Ltd | Hospitality | 2007 |
| Trevedra Farm Holdings Limited | Financial services | 2013 |
| Trevedra Farm Property Limited | Real estate | 2013 |
| Trevelyan Farm Limited | Agriculture & fishing | 1999 |
| Trevine House Management Company Limited | Households | 2025 |
| Trevolt Studio Ltd | Construction | 2025 |
| Trevose Management Company Limited | Households | 2007 |
| Trewellard Garage Limited | Wholesale & retail | 2017 |
| Trewellard Meadery Limited | Hospitality | 2011 |
| Trewidden Enterprises Limited | Energy | 1997 |
| Trink Farm Limited | Real estate | 2006 |
| Tropical Taproom Ltd | Hospitality | 2026 |
| Troytown Ltd | Hospitality | 2011 |
| Truly Cornwall Ltd | Hospitality | 2025 |
| Truthwall Marine Limited | Real estate | 2003 |
| Truthwall Mill Ltd | Other services | 2023 |
| Try-Jockers Limited | Professional & scientific | 2009 |
| Trythall Ltd | Professional & scientific | 2024 |
| TSC Practitioners Ltd | Health & social care | 2023 |
| Ttoc Limited | Hospitality | 2025 |
| Tucker Travel Limited | Transport & logistics | 2012 |
| Turkish Barbers U.K Ltd | Other services | 2019 |
| Twin FIN Film Co. Ltd | Information & communication | 2020 |
| Twisted Animator Productions Ltd | Information & communication | 2026 |
| TWL Associates Ltd | Professional & scientific | 2014 |
| UC Logic Limited | Information & communication | 2025 |
| UK Coach Training Ltd | Professional & scientific | 2021 |
| Underwoods Garage Ltd | Wholesale & retail | 2025 |
| Ungvari Medical Limited | Health & social care | 2019 |
| Union & Western Hotels Limited | Hospitality | 1946 |
| United Writers Publications Limited | Information & communication | 1980 |
| Universal Waters Ltd | Wholesale & retail | 2026 |
| Upper COT Estate Limited | Agriculture & fishing | 2020 |
| Urban Tech Creative Limited | Professional & scientific | 2019 |
| Urban XR Ltd | Information & communication | 2021 |
| V KAN Build Limited | Construction | 2021 |
| V KAN Dental Limited | Real estate | 2015 |
| Vandflow Collective Ltd | Health & social care | 2025 |
| Varfell Farms Ltd | Agriculture & fishing | 1995 |
| Vascular LLP | | 2019 |
| VAULT1UK Ltd | Wholesale & retail | 2025 |
| Velour Hair & Beauty House Ltd | Other services | 2026 |
| Vera Trinder Limited | Wholesale & retail | 1969 |
| Verdite Ltd | Construction | 2023 |
| Viavie Ltd | Education | 2023 |
| Vibrant People Limited | Health & social care | 2022 |
| Villainarcapparel Ltd | Wholesale & retail | 2025 |
| Vino SA Limited | Wholesale & retail | 2018 |
| Vivid Palette Ltd | Wholesale & retail | 2008 |
| Vortex Vape Local Ltd | Wholesale & retail | 2026 |
| Vortex Vape Ltd | Wholesale & retail | 2025 |
| W & W Medical Limited | Health & social care | 2023 |