| THE Performance Automotive Group Limited | Professional & scientific | 2022 |
| THE Plough (Towcester) Ltd | Wholesale & retail | 2015 |
| THE POD Collective Franchise Ltd | Professional & scientific | 2026 |
| THE POD Collective Ltd | Professional & scientific | 2024 |
| THE Primary School Tutor Ltd | Education | 2020 |
| THE Quench Qube Ltd | Wholesale & retail | 2025 |
| THE Recruiters' Guild Ltd | Administrative & support | 2025 |
| THE Resonant Agency Ltd. | Administrative & support | 2016 |
| THE Retina Clinic London Limited | Health & social care | 2020 |
| THE RFT Partnership Limited | Extraterritorial | 2025 |
| THE Sculpted Clinic Limited | Health & social care | 2022 |
| THE Shammy Ltd | Real estate | 2025 |
| THE Shire Retreats & Events Ltd | Arts & recreation | 2024 |
| THE Silverstone Academy Trust | Education | 2011 |
| THE Silverstone Foundation | Arts & recreation | 2026 |
| THE Slow Life Ltd | Wholesale & retail | 2025 |
| THE Small Pet Company Limited | Wholesale & retail | 2011 |
| THE Sofa & Chair Company London Ltd | Manufacturing | 2025 |
| THE Squared Circle Gym Limited | Other services | 2022 |
| THE Stillroom Studio Ltd | Wholesale & retail | 2026 |
| THE Studio Sixpence Ltd | Wholesale & retail | 2022 |
| THE Swim Shed Limited | Arts & recreation | 2010 |
| THE Towcester Museum | Arts & recreation | 2007 |
| THE Traditional Verandah Company Limited | Construction | 2011 |
| THE Triumph Roadster Club Limited | Other services | 2008 |
| THE Tutor Bunker Ltd | Education | 2023 |
| THE Ultimate Pemf MAT Ltd | Wholesale & retail | 2026 |
| THE Various Group Ltd | Professional & scientific | 2020 |
| THE Vault Cocktail Lounge Ltd | Hospitality | 2025 |
| THE Velo Barn Limited | Real estate | 2017 |
| THE Wappenham Stone Co Ltd | Wholesale & retail | 2025 |
| THE Waste Technology Group Limited | Professional & scientific | 2017 |
| THE Wildflower Group Ltd | Professional & scientific | 2021 |
| THE Wildflowers Early Years Ltd | Education | 2022 |
| THE Zozimus Academy Limited | Administrative & support | 2025 |
| Thega Productions Limited | Other services | 2025 |
| Theodore Racing Limited | Arts & recreation | 2014 |
| Think Fitter Ltd | Administrative & support | 2019 |
| Thinking Books Ltd | Wholesale & retail | 2018 |
| Thinking Products Ltd. | Information & communication | 2014 |
| Thirstys.Co.Uk Limited | Administrative & support | 1996 |
| Thomas O Pearson Physiotherapy Limited | Other services | 2021 |
| Thompsons MK Limited | Professional & scientific | 2005 |
| Thoroughbred Properties (Lettings) Ltd | Real estate | 2022 |
| Threl Building + Electrical Services Ltd | Information & communication | 1997 |
| Thumwood & Co Limited | Wholesale & retail | 2018 |
| Tiffield Treats Ltd | Wholesale & retail | 2025 |
| Tilly Prop Ltd | Real estate | 2025 |
| TIM Newton Racing Services Limited | Professional & scientific | 2017 |
| Time 73 Ltd | Hospitality | 2026 |
| Time for YOU (Essex) Limited | Administrative & support | 2023 |
| Tiny Rhino Limited | Wholesale & retail | 2009 |
| TIP Top Carpentry & Building Solutions Ltd | Construction | 2022 |
| TJ Contract Cleaning Solutions Limited | Administrative & support | 2017 |
| Tjes Financial Services Limited | Financial services | 2026 |
| TJS Consulting Limited | Construction | 2025 |
| TK Away Ltd | Extraterritorial | 2018 |
| TK Foodtech Solutions Ltd | Professional & scientific | 2013 |
| TKF Building Maintenance Ltd | Construction | 2019 |
| TKL Events Ltd | Administrative & support | 2025 |
| TLN Saas Holdings Limited | Information & communication | 2026 |
| TM Farms Limited | Arts & recreation | 2020 |
| TMN 24 Hour Locksmith Limited | Administrative & support | 2010 |
| TMS Construction Services Limited | Construction | 2025 |
| Toaster Studio Ltd | Professional & scientific | 2023 |
| Toby Mower Ltd | Manufacturing | 2016 |
| TOM Kerridge Consultancy Limited | Professional & scientific | 2013 |
| TOM Kerridge London Ltd | Professional & scientific | 2018 |
| TOM Kerridge Media Limited | Arts & recreation | 2014 |
| Tontine Saas Limited | Information & communication | 2021 |
| Torque Motorsport Limited | Professional & scientific | 2015 |
| Torus (Music) Ltd | Information & communication | 2021 |
| Total Flooring Solutions Limited | Construction | 2003 |
| Tova Sports Ltd. | Manufacturing | 2023 |
| Tove Accountancy Ltd | Professional & scientific | 1995 |
| Tove Management Ltd | Professional & scientific | 2002 |
| Tove Properties Ltd | Real estate | 2022 |
| Tove Valley Leisure Limited | Administrative & support | 2001 |
| Towbury Court Fine Foods Limited | Manufacturing | 2005 |
| Towcester Classic Cars Limited | Wholesale & retail | 2010 |
| Towcester Curry House Limited | Hospitality | 2022 |
| Towcester Electrical Services Limited | Professional & scientific | 2017 |
| Towcester Financial Planning Limited | Financial services | 2006 |
| Towcester Garage Limited | Wholesale & retail | 2014 |
| Towcester Gazebos Ltd | Administrative & support | 2024 |
| Towcester Masonic Hall Management Company Limited | Households | 2025 |
| Towcester Masonic Hall Property Company Limited | Real estate | 1990 |
| Towcester Mill Brewery Limited | Manufacturing | 2009 |
| Towcester Mill Pubs Limited | Hospitality | 2014 |
| Towcester Research Limited | Professional & scientific | 2013 |
| Towcester Self Storage Limited | Extraterritorial | 2025 |
| Towcester Solutions Ltd | Hospitality | 2024 |
| TOWCESTER183 Limited | Real estate | 2019 |
| Towcesterhomes Limited | Real estate | 2019 |
| Towcestrians Limited | Arts & recreation | 2016 |
| TPC (Automotive) Europe Ltd | Wholesale & retail | 2023 |
| TPC (Automotive) Ltd | Wholesale & retail | 2004 |
| Track Group Ltd | Wholesale & retail | 2025 |
| Track-Club Limited | Arts & recreation | 2013 |
| Track-Powertrain Limited | Arts & recreation | 2011 |