| Timay Ltd | Wholesale & retail | 2024 |
| Time & Chance Service Ltd | Real estate | 2017 |
| Time Brickwork Limited | Construction | 2026 |
| Time for YOU (Hitchin & Letchworth) Ltd | Other services | 2018 |
| Time for YOU (LU) Ltd | Other services | 2017 |
| Time for YOU (SG) Ltd | Other services | 2020 |
| Time for YOU Buckinghamshire Ltd | Other services | 2012 |
| Time for YOU House Cleaners Ltd | Administrative & support | 2015 |
| Time for YOU Southampton East Limited | Administrative & support | 2024 |
| Time for YOU Staines, Egham, Feltham Ltd | Administrative & support | 2026 |
| Time for YOU Thanet and Dover Ltd | Administrative & support | 2023 |
| Time Network Limited | Education | 2022 |
| Time Systems Group Limited | Information & communication | 2006 |
| Time Systems Holdings Limited | Information & communication | 2007 |
| Time Systems Limited | Information & communication | 2004 |
| Timed Film Productions Ltd | Information & communication | 2024 |
| Timeline Project Services Ltd | Construction | 2021 |
| Times of Egypt Limited | Information & communication | 2019 |
| Timeshare Consumer Association Limited | Other services | 2020 |
| Timmins Property Ltd | Real estate | 2025 |
| Timmins Solutions Ltd | Professional & scientific | 2012 |
| Timothy J Smith Limited | Construction | 2012 |
| Timwoc Limited | Health & social care | 2014 |
| TIN Robot Limited | Professional & scientific | 2019 |
| Tina's Trading Ltd | Hospitality | 2025 |
| Tingles Aesthetics Academy Ltd | Other services | 2022 |
| Tingles Aesthetics Limited | Other services | 2022 |
| Tinizine Limited | Information & communication | 2014 |
| Tinocloud Limited | Health & social care | 2014 |
| Tinpee Afro Caribbean Investments Ltd | Wholesale & retail | 2025 |
| Tintern Property Ltd | Hospitality | 2022 |
| Tinuplus Enterprises Limited | Wholesale & retail | 2020 |
| Tiny Penguin Personalised Limited | Extraterritorial | 2018 |
| Tiny Technology Limited | Administrative & support | 2013 |
| Tiny Tents the Super Sleepover Company Ltd | Arts & recreation | 2016 |
| Tiny Tourists Ltd | Information & communication | 2016 |
| Tinysunland Ltd | Professional & scientific | 2019 |
| TIP Top Bouncy Castle & Party Hire Ltd | Other services | 2024 |
| TIP Top Tails MK Ltd | Other services | 2023 |
| TIP Top Venues Ltd | Administrative & support | 2015 |
| Tipam Limited | Health & social care | 2016 |
| Tippytoes Stantonbury Nursery Limited | Education | 2011 |
| Tiptop Properties MK Ltd | Real estate | 2020 |
| Tique Decrorating & Tiling Ltd | Construction | 2025 |
| Tiramai Ltd | Professional & scientific | 2024 |
| Tisco Financial Planning Limited | Financial services | 2005 |
| Tishan Eelam Shopfitters (UK) Limited | Other services | 2019 |
| Tisit Ltd | Information & communication | 2021 |
| Tissue Culture UK Ltd | Wholesale & retail | 2026 |
| Titan Logic Services Ltd | Wholesale & retail | 2026 |
| Titanium Heat Treatment Services Limited | Manufacturing | 2015 |
| Titanium Labs Ltd | Wholesale & retail | 2026 |
| Titivate Ltd | Wholesale & retail | 2022 |
| Tito's Plumbing & Maintenance Services Ltd | Construction | 2019 |
| Titus Property Limited | Real estate | 2024 |
| Tizer Limited | Manufacturing | 1936 |
| Tizzy Trimz Ltd | Other services | 2023 |
| TJ Flower Services Ltd | Wholesale & retail | 2025 |
| TJ Humphries Limited | Construction | 2019 |
| TJ Peanut Ltd | Administrative & support | 2026 |
| TJ Sanctuary Limited | Real estate | 2026 |
| TJE Home Solutions Ltd | Construction | 2022 |
| TJE Technical Services Limited | Professional & scientific | 2024 |
| TJI Carpentry Limited | Manufacturing | 2023 |
| TJM Global Ltd | Wholesale & retail | 2026 |
| TJR Engineering Ltd | Manufacturing | 2011 |
| TJR Planning Limited | Professional & scientific | 2013 |
| Tjrm Limited | Hospitality | 2017 |
| TK Advisory Limited | Professional & scientific | 2023 |
| TK Afro Kitchen Ltd | Hospitality | 2020 |
| TK Cutz Ltd | Other services | 2024 |
| TK Innovations Ltd | Arts & recreation | 2025 |
| TK2 Stitches Ltd | Manufacturing | 2025 |
| TKS Realisations Limited | Manufacturing | 1973 |
| Tksh Properties Ltd | Real estate | 2024 |
| TL Trading Limited | Construction | 2017 |
| Tlap Services Ltd | Information & communication | 2012 |
| TLB Interiors Ltd | Construction | 2022 |
| TLC Landscape Care Ltd | Administrative & support | 2025 |
| TLC Pro Ltd | Professional & scientific | 2024 |
| Tlgk Consulting Limited | Professional & scientific | 2025 |
| TLJ Associates Ltd. | Health & social care | 2013 |
| TLO Lika Limited | Real estate | 2026 |
| TLT Estates Ltd | Real estate | 2025 |
| TLY Financial Services Ltd | Professional & scientific | 2010 |
| TM & JC Doyle Limited | Administrative & support | 2006 |
| TM Constructions-Uk Ltd | Construction | 2018 |
| TM Insulation Ltd | Construction | 2017 |
| Tm-M Home Improvement Ltd | Construction | 2019 |
| Tmaa Limited | Transport & logistics | 2019 |
| TMC Group UK Ltd | Wholesale & retail | 2020 |
| TMI Engineering Ltd | Professional & scientific | 2014 |
| TMN Courier Ltd | Transport & logistics | 2024 |
| TMT Consulting Limited | Professional & scientific | 2023 |
| TMT Tring Ltd | Professional & scientific | 2019 |
| TN Ocean Limited | Wholesale & retail | 2025 |
| TN Talent Recruitment Limited | Administrative & support | 2026 |
| TNA Consulting Ltd | Information & communication | 2018 |
| TNH Enterprises Limited | Manufacturing | 2011 |
| Tnmoc Trading Limited | Wholesale & retail | 2009 |