| T.G. Cutt & SON Limited | Manufacturing | 2003 |
| T.Gen Services Limited | Professional & scientific | 2003 |
| T.H.Hobson (York) Limited | Financial services | 2026 |
| T.H.Hobson Limited | Agriculture & fishing | 1951 |
| T.P. Madgwick Consulting Limited | Professional & scientific | 2017 |
| T.S.L. 23 Ltd | Financial services | 2022 |
| T.S.L. Electrical and Data Services Ltd | Construction | 2006 |
| T.W Electrical York Limited | Construction | 2026 |
| T.W. Fields (Clifton Moor) Limited | Administrative & support | 2013 |
| T.W. Fields Limited | Real estate | 1949 |
| T.W. Robinson (Farmers) Limited | Agriculture & fishing | 1959 |
| T.W. York Properties Ltd | Construction | 2025 |
| T1GER Investments Ltd | Construction | 2024 |
| T3 Coaching Limited | Administrative & support | 2021 |
| T4 York Ltd | Wholesale & retail | 2020 |
| T501 Productions Ltd | Information & communication | 2025 |
| TA & PJ Stephenson Limited | Agriculture & fishing | 2010 |
| Taas Ghar Ltd | Hospitality | 2023 |
| Tabula Rasa NW Ltd | Health & social care | 2006 |
| Tacef Europe Ltd | Other services | 2024 |
| Tackle IT Solutions Ltd | Arts & recreation | 2014 |
| Tactx Grassroots Ltd | Education | 2024 |
| Tactx Ltd | Education | 2024 |
| TAD Networks Ltd | Construction | 2016 |
| Tafraout Ltd | Hospitality | 2026 |
| TAG Brand Solutions Limited | Administrative & support | 2014 |
| TAG House Construction Ltd | Construction | 2011 |
| TAG House Holdings Ltd | Financial services | 2025 |
| TAG House Limited | Construction | 2014 |
| Tagstar Limited | Wholesale & retail | 2014 |
| TAH Chang Limited | Hospitality | 2017 |
| TAH Tien Limited | Hospitality | 2018 |
| Taher Holdings Ltd | Financial services | 2026 |
| Taiga Hare Limited | Financial services | 2022 |
| Takahe Ltd | Information & communication | 2024 |
| Takanomi Limited | Information & communication | 2005 |
| Takeover Distribution Limited | Transport & logistics | 2007 |
| Taking Baby Steps CIC | Health & social care | 2022 |
| Talent Discovery Hub Ltd | Administrative & support | 2024 |
| Talent Edge Consulting Limited | Professional & scientific | 2014 |
| Talent Hound Recruitment Ltd | Administrative & support | 2025 |
| Talisman Subsea Limited | Professional & scientific | 1999 |
| Talk to Mable Limited | Information & communication | 2025 |
| Talking OUT Ltd | Health & social care | 2018 |
| Tallow Build Ltd | Manufacturing | 2024 |
| Tallow Properties Ltd | Real estate | 2024 |
| Talysis Limited | Professional & scientific | 2004 |
| Tamborough Developments Limited | Extraterritorial | 1992 |
| Tame Bridge View Management Company Limited | Households | 2025 |
| Tameside Veterinary Clinic Limited | Professional & scientific | 2008 |
| Tampa Digi Limited | Information & communication | 2025 |
| Tamwood Court Management Company Limited | Real estate | 2024 |
| Tancred Investments Limited | Real estate | 2017 |
| Tandil Investment Management Ltd | Extraterritorial | 2011 |
| Tang Hall Chinese Takeaway Ltd | Hospitality | 2024 |
| Tang Hall Smart C.I.C. | Arts & recreation | 2014 |
| Tang of Tang Hall Ltd | Hospitality | 2024 |
| Tangent Vision Limited | Information & communication | 2021 |
| Tangled Hair and Beauty (York) Limited | Other services | 2018 |
| Tanijo Bros Limited | Hospitality | 2025 |
| Tanker Consulting Services Limited | Administrative & support | 2016 |
| Tanner ROW Apartments Limited | Households | 1996 |
| Tansy Construction Limited | Construction | 2021 |
| Tantami Locums Limited | Health & social care | 2018 |
| Tanur Ltd | Wholesale & retail | 2015 |
| Tanya Bridge Fisheries Ltd | Hospitality | 2026 |
| Tanza Kindness Ltd | Wholesale & retail | 2026 |
| TAP and Growler Yorkshire Ltd | Hospitality | 2017 |
| Taplanes Shower Solutions Limited | Manufacturing | 2025 |
| Tapped Newcastle Limited | Hospitality | 2016 |
| Tapped York Limited | Hospitality | 2015 |
| Tappt Global Ltd | Wholesale & retail | 2025 |
| Tappt Ltd | Wholesale & retail | 2025 |
| Tara Marketing Ltd | Professional & scientific | 2019 |
| Target Fitness (Yorkshire) Ltd | Other services | 2022 |
| Target Scaffolding York Limited | Construction | 2016 |
| Targit IT Limited | Information & communication | 2017 |
| Tarnhelm Securities Limited | Financial services | 1986 |
| Taro Property Ltd | Real estate | 2021 |
| Tarraby View (Carlisle) Management Company Limited | Households | 2017 |
| TAS Auto Centre Ltd | Wholesale & retail | 2025 |
| TAS Site Services Limited | Construction | 2025 |
| Tasca Easingwold Ltd | Hospitality | 2024 |
| Tasca Holdings Ltd | Financial services | 2026 |
| Tasha's Cleaning Services Ltd | Administrative & support | 2025 |
| Tasha's Tubs Limited | Administrative & support | 2025 |
| Task Parking Solution Ltd | Other services | 2025 |
| Task Personnel Solutions Limited | Administrative & support | 2012 |
| Taso Consulting Limited | Professional & scientific | 2011 |
| Tastes of Italy Limited | Administrative & support | 2000 |
| Tatalina Ltd | Real estate | 2025 |
| Tate Exploration Consultants Ltd. | Mining & quarrying | 1998 |
| Taterson Ltd | Construction | 2026 |
| Tatm Ltd | Arts & recreation | 2023 |
| Taton Ltd | Administrative & support | 2017 |
| Tattco Digital Ltd | Information & communication | 2026 |
| Taurus Court Management Company Limited | Households | 1994 |
| Taurus Housing (York) Limited | Extraterritorial | 1985 |
| Taurus Investments Limited | Wholesale & retail | 1998 |
| Tavistock House Hotel Limited | Hospitality | 2016 |