| THE Whole Pack Theatre Ltd | Arts & recreation | 2024 |
| THE Wholesale Butchers Ltd. | Wholesale & retail | 2015 |
| THE Wicked Cake Co. Limited | Manufacturing | 1991 |
| THE Wickets (Trumpington) Management Company Ltd | Households | 2018 |
| THE Wildlife Trust for Bedfordshire, Cambridgeshire and Northamptonshire | Other services | 1990 |
| THE Willcox Collective Ltd | Information & communication | 2019 |
| THE Willow Education Limited | Education | 2020 |
| THE Willows & Blooms Group Ltd | Education | 2026 |
| THE Windmill Kennels and Cattery Limited | Administrative & support | 2002 |
| THE Wonder of Wood Cambridge Limited | Administrative & support | 2022 |
| THE Wordling Limited | Education | 2015 |
| THE Works Landscaping Ltd | Construction | 2015 |
| THE World United Party Group Limited | Other services | 2025 |
| THE Write Idea Limited | Manufacturing | 2004 |
| THE44 Ltd | Professional & scientific | 2024 |
| Thealkemy Limited | Professional & scientific | 2025 |
| Theannyshop Limited | Wholesale & retail | 2011 |
| Thefurnished Ltd | Wholesale & retail | 2023 |
| Thehireworks Ltd | Administrative & support | 2020 |
| Theia Insights Ltd | Professional & scientific | 2022 |
| Theimpact Limited | Health & social care | 2020 |
| Theoneplug Limited | Wholesale & retail | 2024 |
| Theopenreality Ltd | Information & communication | 2024 |
| Theproslocker LLP | | 2024 |
| Theraccines Ltd | Health & social care | 2015 |
| Therachain Limited | Information & communication | 2025 |
| Thermal Exchange Limited | Manufacturing | 1991 |
| Thermal Process Solutions Limited | Professional & scientific | 2013 |
| Thermoteknix Systems Limited | Manufacturing | 1982 |
| Thestone Ltd | Manufacturing | 2025 |
| Thewillowtree Ltd | Hospitality | 2024 |
| They WHO Dare Ltd | Professional & scientific | 2026 |
| Theypray Ltd | Information & communication | 2025 |
| Thiago Composites Ltd | Manufacturing | 2026 |
| Thierry-Health Ltd | Health & social care | 2015 |
| Thimbleby Hill Residents Management Company Limited | Households | 2018 |
| Think Audio Visual Limited | Professional & scientific | 2006 |
| Think Careerly Ltd | Other services | 2025 |
| Think Human Consultancy Ltd | Professional & scientific | 2026 |
| Think Three Ltd | Professional & scientific | 2012 |
| Think Unthinkable Limited | Administrative & support | 2017 |
| Thinkawdenergy Ltd | Construction | 2023 |
| Thinkspark Ltd | Education | 2024 |
| Third Millennium Technology Limited | Information & communication | 2025 |
| Thirst AID (U K) Limited | Financial services | 2002 |
| Thirst First Ltd | Hospitality | 2012 |
| Thirsty Cambridge Limited | Hospitality | 2015 |
| Thirteen One Holdings Limited | Real estate | 2026 |
| Thirty Two Foxhollow Limited | Extraterritorial | 2024 |
| Thiru Trading Ltd | Wholesale & retail | 2020 |
| This IS Hera Hair Ltd | Other services | 2020 |
| This IS Human Ltd | Professional & scientific | 2018 |
| This Land Development Limited | Construction | 2018 |
| This Land Finance Limited | Construction | 2018 |
| This PL Ltd | Professional & scientific | 2024 |
| This Place Holdings Limited | Professional & scientific | 2023 |
| Thispower Holdings Ltd | Extraterritorial | 2013 |
| Thistlemoor Investment Fund Limited | Real estate | 2007 |
| Thittala & Co Ltd | Professional & scientific | 2026 |
| Thomas Aveling Close Management Company Limited | Real estate | 2021 |
| Thomas Composites Ltd | Manufacturing | 2024 |
| Thomas Cope Medical Consulting Limited | Health & social care | 2023 |
| Thomas Properties Investment Ltd | Real estate | 2025 |
| Thomas Sykes Holdings Ltd | Financial services | 2025 |
| Thomas Watts Machines and Controls Limited | Administrative & support | 2002 |
| Thomas Wolsey Property Limited | Administrative & support | 2017 |
| Thomasray Ltd | Manufacturing | 2024 |
| Thompson Electrical (Cambridge) Limited | Construction | 1986 |
| Thomson Webb & Corfield LLP | | 2015 |
| Thorbow Investments Limited | Real estate | 2021 |
| Thornbury Residents Limited | Real estate | 2004 |
| Thorney Power Limited | Manufacturing | 2021 |
| Thorney Road (Phase 5) Limited | Households | 2015 |
| Thornleigh House Ltd | Professional & scientific | 2026 |
| Thornley Developments LLP | | 2015 |
| Thornton Property Rental Limited | Real estate | 2017 |
| Thorp Electrical Ltd | Other services | 2018 |
| Thorpe Lakes Ltd | Agriculture & fishing | 2014 |
| Thorpe LEA (GT Chesterford) LLP | | 2016 |
| Those History People Ltd | Education | 2019 |
| Thoth Open Metadata Community Interest Company | Information & communication | 2022 |
| Thoughtfully Wild Ltd | Wholesale & retail | 2026 |
| Thousand Keys Group Limited | Real estate | 2019 |
| Three by Three Games Ltd | Manufacturing | 2026 |
| Three Carter Design Ltd | Professional & scientific | 2019 |
| Three Cats Trading Limited | Professional & scientific | 2011 |
| Three Counties Healthcare Supplies Ltd | Wholesale & retail | 2020 |
| Three Gems Education and Consulting Ltd | Professional & scientific | 2022 |
| Three Horseshoes Comberton Ltd | Hospitality | 2023 |
| Three in the Sea Ltd | Manufacturing | 2026 |
| Three Orchards Ltd | Professional & scientific | 2019 |
| Three Sixty Information Security Ltd | Information & communication | 2002 |
| Three T Company Ltd | Financial services | 2019 |
| Three to One Films Ltd | Information & communication | 2021 |
| Three Willows Accommodation Ltd | Hospitality | 2022 |
| Threepoints Tech Ltd | Manufacturing | 2025 |
| Threetrees (Burwell) Limited | Other services | 2020 |
| Thriplow Group Ltd | Financial services | 2018 |
| Thriplow Services Limited | Construction | 2018 |
| Thrive Enterprises (Cambridge) C.I.C. | Hospitality | 2020 |