| TDN Structural Limited | Professional & scientific | 2012 |
| Teak Garden Furniture Ltd | Manufacturing | 2021 |
| Teak Solutions Limited | Manufacturing | 2017 |
| Team Green Energy Services Ltd | Professional & scientific | 2022 |
| Team Tilly Leisure Ltd | Hospitality | 2023 |
| Teamfield Limited | Administrative & support | 1998 |
| TEC BIM Solutions Ltd | Professional & scientific | 2024 |
| TEC Property Letting Ltd | Real estate | 2024 |
| Tech and Games Europe Ltd | Manufacturing | 2024 |
| Tech Pool Recruitment Limited | Administrative & support | 2021 |
| Techbyte IT Solutions Ltd. | Information & communication | 2025 |
| Technical EX Services Limited | Construction | 2011 |
| Techsofthub Ltd | Wholesale & retail | 2024 |
| Teckgate Ltd | Information & communication | 2023 |
| TEE Pee's Properties Ltd | Real estate | 2018 |
| Tees Dents Ltd | Wholesale & retail | 2024 |
| Tees Electrical Limited | Construction | 2018 |
| Tees Lock Conversion Limited | Manufacturing | 2009 |
| Tees Mechanical Services Ltd | Professional & scientific | 2023 |
| Tees Property Services Group Ltd | Construction | 2026 |
| Tees Valley Props Ltd | Administrative & support | 2026 |
| Tees Valley Swim School LLP | | 2016 |
| Teeside Building Services Limited | Construction | 2025 |
| Teesside CAD Solutions Limited | Professional & scientific | 2016 |
| Teesside ENG Ltd | Professional & scientific | 2023 |
| Teesside Engineering Ltd | Manufacturing | 2025 |
| Teesside Groundworks Ltd | Construction | 2016 |
| Teesside Gynaecology Limited | Health & social care | 2019 |
| Teesside Inspection Services Ltd | Professional & scientific | 2008 |
| Teesside Mobility Ltd | Construction | 2022 |
| Teesside Plant Training Limited | Administrative & support | 2023 |
| Teesside Plastering Services Ltd | Construction | 2021 |
| Teesside Property Investments Ltd | Construction | 2020 |
| Teesside Property Solutions Ltd | Real estate | 2009 |
| Teesside Skip Hire & Waste Management Limited | Other services | 2016 |
| Teesside Stairlifts Ltd | Manufacturing | 2022 |
| Teesside Stays Ltd | Real estate | 2024 |
| Teesside Wardrobes Ltd | Construction | 2026 |
| Telerad Ltd | Health & social care | 2016 |
| Tendril Ventures Ltd | Real estate | 2025 |
| Tennis Outlaws Limited | Arts & recreation | 2014 |
| Terraursa Limited | Professional & scientific | 2020 |
| TES Total Energy Solutions Limited | Professional & scientific | 2013 |
| TFL Electrical Limited | Construction | 2026 |
| Tghospitality Limited | Hospitality | 2023 |
| TH Employ Hire Ltd | Administrative & support | 2019 |
| TH Equipment Hire Limited | Administrative & support | 2018 |
| THE 2 Stroke Barn Ltd | Real estate | 2017 |
| THE Ampersand Foundation | Other services | 2015 |
| THE AMY Brand X Limited | Professional & scientific | 2025 |
| THE Baker's Court (Hartlepool) Management Company Limited | Real estate | 2007 |
| THE Beauty Depot Ltd | Wholesale & retail | 2025 |
| THE Blinds Guru Ltd | Other services | 2025 |
| THE Castle Eden Masonic Hall Company, Limited | Other services | 1924 |
| THE Cleveland Dwellings Limited | Construction | 1935 |
| THE Coach Inn Company Limited | Hospitality | 1998 |
| THE Comfort Zone Hartlepool Limited | Other services | 2022 |
| THE Corner Photography Ltd | Professional & scientific | 2026 |
| THE Cracknell Family LLP | | 2025 |
| THE Craft Container Catering Ltd | Hospitality | 2022 |
| THE Cubhouse Outdoor Nursery Ltd | Education | 2026 |
| THE Drunken Duck Seaton Ltd | Hospitality | 2026 |
| THE Eight Acre Farm Investment Limited | Financial services | 2023 |
| THE Expanded Metal Company Limited | Manufacturing | 2005 |
| THE Extra Yard Community Project CIC | Education | 2023 |
| THE Extra Yard Group Ltd | Information & communication | 2023 |
| THE Fens PUB Limited | Hospitality | 2023 |
| THE Fireplace Hartlepool Limited | Hospitality | 2026 |
| THE Fishing Syndicate Ltd | Wholesale & retail | 2025 |
| THE Gifting Knot Ltd | Professional & scientific | 2022 |
| THE Glam LAB X Ltd | Other services | 2024 |
| THE Golden Crumbs Ltd | Hospitality | 2025 |
| THE Goyle Partnership Limited | Information & communication | 2015 |
| THE Greatham Foundation Ltd | Health & social care | 2008 |
| THE Hanging Monkey Limited | Hospitality | 2019 |
| THE Happy RAT Co Ltd | Information & communication | 2000 |
| THE Head of Steam Limited | Hospitality | 1979 |
| THE Headland Clinic Ltd | Health & social care | 2004 |
| THE Headland Inn Limited | Hospitality | 2022 |
| THE Herbal Centre Ltd | Wholesale & retail | 2019 |
| THE Hideaway Cocktail Bar & Eatery Ltd | Hospitality | 2024 |
| THE Hideaway NE Limited | Other services | 2022 |
| THE Holiday Home Estate Agency Limited | Real estate | 2019 |
| THE House of Cat Creations Ltd | Manufacturing | 2024 |
| THE Hype Hartlepool Ltd | Other services | 2025 |
| THE Independent Agent Ltd | Real estate | 2020 |
| THE INK Doctor Ltd | Other services | 2017 |
| THE Joinery and Carpentry Co Limited | Manufacturing | 2026 |
| THE Label Mboro Ltd | Wholesale & retail | 2019 |
| THE Laser Room North East Limited | Health & social care | 2023 |
| THE Leeds Brewery Holding Company Limited | Professional & scientific | 2011 |
| THE Loaves & Fishes Company 1960 Limited | Wholesale & retail | 2012 |
| THE Lost Tower Tattoo Ltd | Arts & recreation | 2023 |
| THE Lucy Patterson Ltd | Administrative & support | 2023 |
| THE Mindful Project C.I.C. | Information & communication | 2024 |
| THE Mucky PUB Company Limited | Hospitality | 2020 |
| THE New Alma Inn Ltd | Hospitality | 2025 |
| THE Northern Studios (Hartlepool) Limited | Information & communication | 2020 |
| THE Optimum Group Limited | Manufacturing | 2009 |
| THE Original Mortgage Company Ltd | Financial services | 2010 |