| Synthesis Property Limited | Real estate | 2020 |
| SYS BUG IT Solutions Limited | Information & communication | 2023 |
| Sysabri Limited | Professional & scientific | 2026 |
| Systemora Consulting Limited | Professional & scientific | 2021 |
| Systems Power (Holdings) Limited | Financial services | 2013 |
| Systen Defence Limited | Health & social care | 2019 |
| SYV Tech Limited | Information & communication | 2025 |
| Szarr Properties Ltd | Real estate | 2026 |
| Szshah Limited | Health & social care | 2016 |
| T & H Developments Limited | Construction | 2018 |
| T & M Venture Assets Limited | Real estate | 2020 |
| T & Z Medic Consultancy UK Limited | Health & social care | 2023 |
| T and T Abbey Ltd | Other services | 2015 |
| T Houston Ltd | Health & social care | 2025 |
| T Lambert Construction Ltd | Construction | 2025 |
| T S Coffee Ltd | Hospitality | 2025 |
| T&T Fortune Properties UK Limited | Real estate | 2020 |
| T'S RUM Ltd | Wholesale & retail | 2023 |
| T-O-Design & Engineering Limited | Administrative & support | 2014 |
| T. & S. Management Limited | Real estate | 2003 |
| T.J.S. Kent Limited | Construction | 2000 |
| T.P.Car Sales Limited | Wholesale & retail | 2015 |
| T.S.Hattersley & SON Limited | Manufacturing | 1965 |
| T50 Gymnastics Limited | Arts & recreation | 2018 |
| TA Rail Services Limited | Professional & scientific | 2026 |
| Taaco Limited | Real estate | 2024 |
| Taara Consultancy Ltd | Information & communication | 2013 |
| TAB - Testing and Beyond Limited | Information & communication | 2017 |
| Tabeeb Limited | Wholesale & retail | 2022 |
| Tablesign Limited | Professional & scientific | 1991 |
| Tabley Mews Management Company Limited | Households | 2022 |
| Tabley Properties Limited | Real estate | 1993 |
| Tabley Stables (Management) Company Limited | Households | 1995 |
| Tabriz Holdings Ltd | Other services | 2025 |
| Tada Properties Ltd | Real estate | 2021 |
| Tageldin Neurocare Ltd | Health & social care | 2026 |
| Tahira Associates Ltd | Real estate | 2017 |
| TAI CHI Centre Limited | Arts & recreation | 2016 |
| Tailfin Digital Limited | Information & communication | 2023 |
| Tailor CV Ltd | Information & communication | 2025 |
| Tailored Hearing Solutions Ltd | Wholesale & retail | 2017 |
| Taimoordaanish and Co Limited | Financial services | 2012 |
| Taiz Logistics Limited | Transport & logistics | 2025 |
| Take a Look C.I.C. | Health & social care | 2025 |
| Take on Safety Limited | Professional & scientific | 2019 |
| Takyi Studio Limited | Administrative & support | 2022 |
| Talbot Road Fraser Homes Limited | Construction | 2025 |
| Talea Dental Ltd | Health & social care | 2025 |
| Talent Build Solutions Limited | Administrative & support | 2021 |
| Talibi Properties Ltd | Real estate | 2025 |
| Talis Books Limited | Information & communication | 2023 |
| Talk to Sara Ltd | Other services | 2010 |
| Tall Studios Limited | Information & communication | 2010 |
| Talon Petroleum (UK) Limited | Financial services | 2018 |
| TAM Stores Limited | Wholesale & retail | 2023 |
| Tamarillo Ltd | Professional & scientific | 2023 |
| Tamayuz Limited | Health & social care | 2011 |
| Tamayuz Property Investments Limited | Real estate | 2020 |
| Tame Valley Limited | Real estate | 1995 |
| Tams Fashion House Limited | Other services | 2022 |
| Tandonco Ltd | Health & social care | 2025 |
| Tang Dynasty Dining Ltd | Hospitality | 2026 |
| Tania Flexi Solutions Limited | Administrative & support | 2024 |
| Tanishque Ltd | Information & communication | 2019 |
| Tanush Technologies Limited | Administrative & support | 2017 |
| Tanya Birkett Consultancy Ltd | Professional & scientific | 2024 |
| Tapdur Limited | Professional & scientific | 2026 |
| Tapton Court Management Company Limited | Households | 2023 |
| TAR Sprayers Limited | Wholesale & retail | 2015 |
| Tara Williams Investments Ltd | Financial services | 2012 |
| Tardis Construct Ltd | Real estate | 2025 |
| Targe Consulting Ltd | Professional & scientific | 2019 |
| Target Shipping and Trading Limited | Other services | 2024 |
| Tarplett Holdings Limited | Financial services | 2019 |
| Task Force for Family Wellfare | Health & social care | 2018 |
| Taste for Life Limited | Professional & scientific | 2015 |
| Taste of Rome Limited | Hospitality | 2025 |
| Tasty Records Limited | Wholesale & retail | 2021 |
| Tate Consultants Limited | Real estate | 2025 |
| Tatton Estate Management Limited | Real estate | 2013 |
| Tatton Living Limited | Real estate | 2021 |
| Tatton Project Management Ltd | Construction | 2022 |
| Tatton Trust Company Limited | Financial services | 2021 |
| TAU XL Limited | Administrative & support | 2023 |
| Tauri Tatra Ltd | Real estate | 2022 |
| Taurus Software and Consulting Limited | Information & communication | 2014 |
| Taurus-Tells Limited | Wholesale & retail | 2017 |
| Tavern Hospitality Ltd | Hospitality | 2019 |
| Tavern OTG Ltd | Hospitality | 2023 |
| Tavi Recruitment Limited | Administrative & support | 2026 |
| Tax Advisory & Consultancy Services Ltd | Professional & scientific | 2022 |
| Taxation Consultancy Limited | Professional & scientific | 2003 |
| Taxhut Accountancy Ltd | Professional & scientific | 2020 |
| Taxmere Estates Limited | Agriculture & fishing | 1976 |
| Taxundo Limited | Professional & scientific | 2005 |
| TAY Mills (Dundee) Limited | Real estate | 2008 |
| Taylor & Tait Limited | Professional & scientific | 2010 |
| Taylor Christou & Co Ltd | Professional & scientific | 2026 |
| Taylor Legal Limited | Professional & scientific | 2024 |
| Taylor Made Coaching Limited | Arts & recreation | 2020 |