| Taith Consulting Limited | Information & communication | 2019 |
| TAL Y Foel Limited | Professional & scientific | 1998 |
| TAL Y Foel Training Limited | Administrative & support | 1998 |
| Taldrwst CYF | Mining & quarrying | 2019 |
| Talents Outreach Associates CIC | Arts & recreation | 2026 |
| Tarmaster Design Limited | Professional & scientific | 2002 |
| Tarquin Shipley Limited | Professional & scientific | 2016 |
| Tarrabourne Limited | Real estate | 1975 |
| TASSEE2 Ltd. | Wholesale & retail | 2017 |
| Tavistock Protect Limited | Financial services | 2012 |
| Tawa Online CYF. | Information & communication | 2023 |
| Tax Enquiry Solutions Limited | Financial services | 2012 |
| Tay's 1 Ltd | Hospitality | 2025 |
| Taylor Ferran Ltd | Information & communication | 2024 |
| Taylor Mcdowell Limited | Professional & scientific | 2019 |
| Tbarton Electrical Ltd | Construction | 2025 |
| TC 4 HGV Ltd | Education | 2021 |
| TDL Event Services Limited | Extraterritorial | 2013 |
| Teal Farms (NI) Ltd | Construction | 2025 |
| Tec-Band Innovations Ltd | Manufacturing | 2025 |
| Tech Fone Ltd | Wholesale & retail | 2021 |
| Teddy's Bar & Grill Limited | Hospitality | 2022 |
| Teejac Property Group Ltd | Real estate | 2017 |
| Teejac Sports Ltd | Manufacturing | 1997 |
| Tempest Developments Ltd | Construction | 2023 |
| Tempest Engineering Solutions Ltd | Information & communication | 2021 |
| TEN Acres Estates Limited | Real estate | 2024 |
| Terahss CIC | Professional & scientific | 2024 |
| Terimar Management Limited | Administrative & support | 2026 |
| Terrestrial Software Ltd | Information & communication | 2021 |
| Terry Bradley Art Limited | Professional & scientific | 2015 |
| Terry Owen Plastering Limited | Construction | 2025 |
| TG Southall Limited | Construction | 2021 |
| TH Hydro Ltd | Professional & scientific | 2026 |
| Thalassa Management Limited | Extraterritorial | 2003 |
| That PPF GUY Ltd | Wholesale & retail | 2025 |
| That Prize GUY Ltd | Information & communication | 2020 |
| THE Abbey Climbing Centre Limited | Arts & recreation | 2012 |
| THE Bearded Goat Industries Ltd | Hospitality | 2021 |
| THE Best International Services Co Ltd | Financial services | 2025 |
| THE Big Boss Media Ltd | Information & communication | 2025 |
| THE Boat Cottage Limited | Hospitality | 2025 |
| THE Bookkeeping & Consultancy Company (NI) Ltd | Professional & scientific | 2023 |
| THE Change Trust C.I.C. | Education | 2025 |
| THE Chaos Academy Ltd | Arts & recreation | 2025 |
| THE Character Co. NI Ltd | Hospitality | 2025 |
| THE Clandeboye Lakes (1) Limited | Construction | 2020 |
| THE Clandeboye Lakes (2) Limited | Construction | 2020 |
| THE Clandeboye Lakes (3) Limited | Construction | 2020 |
| THE Club Bangor Ltd | Arts & recreation | 2025 |
| THE Community Vault Ltd | Arts & recreation | 2026 |
| THE Cornmill Service Company Limited | Households | 2006 |
| THE Dentman Car Body & Paint Ltd | Wholesale & retail | 2024 |
| THE Dog Field (N.I.) Limited | Other services | 2021 |
| THE Dog Field Groom Room (N.I.) Limited | Wholesale & retail | 2024 |
| THE Donkey Shop Ltd | Wholesale & retail | 2021 |
| THE Dressmaker's Apprentice Ltd | Professional & scientific | 2020 |
| THE Flat Pack MAN NI Ltd | Construction | 2022 |
| THE Flat Pack MAN Scotland Ltd | Construction | 2025 |
| THE Flooring Studio (North Wales) Ltd | Wholesale & retail | 2024 |
| THE Flower Box Limited | Other services | 2025 |
| THE Friends of Treborth Botanic Garden | Professional & scientific | 2007 |
| THE Gill Corporation Europe Limited | Manufacturing | 1997 |
| THE Gray Bear Company Ltd | Wholesale & retail | 2022 |
| THE Happy Health Coaches Ltd | Professional & scientific | 2020 |
| THE Hole in the Hedge Cafe Ltd | Hospitality | 2018 |
| THE Lawn Wizard Ltd | Administrative & support | 2011 |
| THE Lore School Ltd | Education | 2024 |
| THE MAD Hatter Studio Ltd | Manufacturing | 2017 |
| THE Magician's Niece Limited | Information & communication | 2013 |
| THE Management Consulting Bureau Limited | Professional & scientific | 2020 |
| THE Medical Rooms Ltd | Health & social care | 2023 |
| THE Menai Seafood Company Limited | Wholesale & retail | 2020 |
| THE Menai Strait Fishery Order Management Association | Other services | 2010 |
| THE Mortgage and Financial Advice Place Ltd | Financial services | 2013 |
| THE Motor Gym Limited | Wholesale & retail | 2010 |
| THE NI Magic Maker Ltd | Administrative & support | 2025 |
| THE Old Boat House (Anglesey) Ltd | Hospitality | 2005 |
| THE Outdoor Agency Ireland Limited | Wholesale & retail | 2021 |
| THE Panoramic Wheel Company Limited | Arts & recreation | 2017 |
| THE Pirates DEN Cyfyngedig | Hospitality | 2023 |
| THE Property People Group Limited | Professional & scientific | 2001 |
| THE Rabbit Rooms Limited | Hospitality | 2010 |
| THE Real Car Company Limited | Wholesale & retail | 1999 |
| THE Regent Tea Rooms Ltd | Hospitality | 2022 |
| THE Singing Kettle Bakery Ltd | Wholesale & retail | 2015 |
| THE Sneaky Kitchen Co Limited | Hospitality | 2020 |
| THE Sofaman Interiors Ltd | Wholesale & retail | 2021 |
| THE ST Mary's and ST Giles' Centre | Education | 2010 |
| THE Stables (RP) Ltd | Real estate | 2020 |
| THE TAI Pont TWR Residents Association Limited | Extraterritorial | 2006 |
| THE Travel Guys Ltd | Administrative & support | 2023 |
| THE Vape Store Bangor Ltd | Wholesale & retail | 2023 |
| THE Vaults (Bangor) Ltd | Hospitality | 2024 |
| THE Waterside Consortium Limited | Manufacturing | 2023 |
| THE Web Theatre Ltd | Arts & recreation | 2010 |
| Theclimbingastronaut Ltd | Wholesale & retail | 2022 |
| Thella Films Ltd | Information & communication | 2025 |
| Thetreehole Ltd | Real estate | 2026 |
| Thip Therapy & Sport Massage Limited | Health & social care | 2023 |