| Propsource NE Ltd | Real estate | 2024 |
| PX (Tgpp) Limited | Energy | 2002 |
| PX Americas Holdco Limited | Financial services | 2024 |
| PX Appointments Limited | Professional & scientific | 2003 |
| PX Engineering Consultants Limited | Professional & scientific | 2006 |
| PX HOLDCO1 Limited | Financial services | 2021 |
| PX HOLDCO2 Limited | Financial services | 2021 |
| PX HOLDCO3 Limited | Financial services | 2021 |
| PX Holdings Limited | Professional & scientific | 2002 |
| PX Limited | Energy | 2002 |
| PX Supply Limited | Energy | 2017 |
| PX UK HOLDCO3 Limited | Financial services | 2016 |
| PX Water Limited | Energy | 2006 |
| Rachel Jason Property Ltd | Households | 2024 |
| Redheugh Group Ltd | Financial services | 2024 |
| Renew and Sustain Limited | Other services | 2021 |
| Right House NE Ltd | Real estate | 2019 |
| Saltend Chemicals Park Limited | Manufacturing | 2016 |
| SDS Property Solutions Limited | Professional & scientific | 2014 |
| Silkwood Group Ltd | Construction | 2025 |
| Sold in Seconds Warehouse Ltd | Wholesale & retail | 2026 |
| Sorbonne Management Ltd | Real estate | 2024 |
| Spear-Head Sales Support Ltd | Administrative & support | 2024 |
| Spyglass Engineering Services Limited | Professional & scientific | 2017 |
| Stagdale Holdings Limited | Real estate | 2023 |
| Stockton and Billingham College Developments Limited | Construction | 1999 |
| Sugarcup NE Ltd | Hospitality | 2024 |
| Teesside School of Music Limited | Education | 2011 |
| Teesside Taproom Ventures Ltd | Hospitality | 2025 |
| THE Playground Thornaby Limited | Health & social care | 2021 |
| Thornaby FC 2026 Ltd | Arts & recreation | 2026 |
| Thornaby Green Holdings Ltd | Real estate | 2025 |
| Thornaby Training & Consultancy Limited | Information & communication | 2024 |
| Urban Elite Builders Ltd | Construction | 2025 |
| Vixen Properties Limited | Real estate | 2009 |
| Vixen Surface Treatments Limited | Manufacturing | 2009 |
| W.D. Vulcanisers Limited | | 1984 |
| Waller Wear Ltd | Wholesale & retail | 2026 |
| Wetherill Limited | Wholesale & retail | 2025 |
| Wilson Drummond Bespoke Kitchens & Bedrooms Limited | Construction | 2002 |
| Wooco Ltd | Real estate | 2026 |
| Woods Bros Cleaning Contractors Ltd | Administrative & support | 2015 |