| Thalassa Management (NO.2) Limited | Households | 2008 |
| Thames Trader Limited | Construction | 2020 |
| THE Apron Hospitality Ltd | Hospitality | 2026 |
| THE Autodock Ltd | Administrative & support | 2015 |
| THE Ballyclare High School Foundation Ltd | Other services | 2022 |
| THE Blak Sheep Ltd | Manufacturing | 2025 |
| THE Brackens Land Management Ltd | Households | 2017 |
| THE Cairn Management Limited | Extraterritorial | 2010 |
| THE Clinic Ballyclare Ltd | Other services | 2025 |
| THE Collop Management Company Limited | Households | 2022 |
| THE Courtyard at Broomhill Limited | Households | 2010 |
| THE Crib Entertainment Ltd | Arts & recreation | 2022 |
| THE Design Yard Ltd | Manufacturing | 2025 |
| THE Elms Land Management Ltd | Extraterritorial | 2014 |
| THE Honest Harvest Ltd | Hospitality | 2026 |
| THE Human Kind Foundation | Education | 2020 |
| THE Mill Pond Management Company Limited | Extraterritorial | 2005 |
| THE Old Mill Management Company (Newtownabbey) Limited | Real estate | 2016 |
| THE Olde Nursery Management Co Ltd | Extraterritorial | 2010 |
| THE Original Used Clothing Co Limited | Wholesale & retail | 2012 |
| THE Plant Label Company Limited | Wholesale & retail | 2022 |
| THE Poplars Land Management Ltd | Real estate | 2002 |
| THE Quiet Crumb Ltd | Manufacturing | 2025 |
| THE RDG Spot Limited | Hospitality | 2025 |
| THE Rental Partnership Ballyclare Ltd | Real estate | 2013 |
| THE Rose Garden (Derriaghy) Management Ltd | Extraterritorial | 2006 |
| THE Rowans Ballynure Management Limited | Households | 2016 |
| THE Spires Land Management Ltd | Real estate | 2002 |
| THE Steadings (Newtownards) Management Limited | Households | 2019 |
| THE Wardrobe Limited | Wholesale & retail | 2002 |
| THE WEE Village Ltd | Education | 2020 |
| THE Willows (Crumlin) Management Ltd | Households | 2016 |
| Thermal Impact Group Ltd. | Manufacturing | 2018 |
| Thompson Hearing Services Ltd | Health & social care | 2016 |
| Thornberry (Ballyclare) Land Management Ltd | Households | 2023 |
| Thornberry Property Management Ltd | Extraterritorial | 2004 |
| Thornhill Caravan & Motorhome Services Ltd | Wholesale & retail | 2022 |
| Thralcot Lane Management Limited | Real estate | 2015 |
| Throatlake Consulting Limited | Professional & scientific | 2010 |
| Throatlake Ltd | Wholesale & retail | 2004 |
| Throne View Management Company Limited | Extraterritorial | 2007 |
| Tiliston Ltd | Real estate | 2023 |
| Time Coffee House Limited | Hospitality | 2022 |
| Titan Automation Group Ltd | Information & communication | 2025 |
| Titan One Limited | Manufacturing | 2025 |
| TMC Vehicle Solutions Ltd | Manufacturing | 2025 |
| TMP Tyres Ltd | Wholesale & retail | 2025 |
| Tolvin Contractors Limited | Construction | 2006 |
| Tornado Wind Systems N.I. Limited | Energy | 2013 |
| Totallyhot NI Limited | Manufacturing | 2016 |
| Trade Printing Group Ltd | Manufacturing | 2015 |
| Trainedbyaj Limited | Arts & recreation | 2025 |
| Travel Affiliation Ltd | Administrative & support | 2011 |
| TRIANGL8 Ltd | Information & communication | 2025 |
| Triverity Laboratories Limited | Professional & scientific | 2020 |
| TSW Automotive Limited | Wholesale & retail | 2019 |
| TVS Property Ltd | Real estate | 2019 |
| TWB Firewood Ltd | Wholesale & retail | 2022 |
| Tweedies Inn Ltd | Hospitality | 2026 |
| Tyrereader Ltd | Manufacturing | 2017 |
| UDL115 Land Management Ltd | Households | 2022 |
| Ulster Estates Limited | Real estate | 1964 |
| Ulster Vintage Commercial Vehicle Club Limited | Other services | 2007 |
| Under the Drum Events CIC | Arts & recreation | 2026 |
| Under the Drum Ltd | Administrative & support | 2024 |
| Upper Gateside Grove Management Company Limited | Households | 2014 |
| Upton Court Apartments (Templepatrick) Limited | Households | 1987 |
| Vaeh Vanna Ltd | Wholesale & retail | 2024 |
| Valetta Falcon Limited | Professional & scientific | 2012 |
| Vapis (NI) Limited | Manufacturing | 2021 |
| Vaxt Hire Ltd | Administrative & support | 2019 |
| Venn Heating Plumbing & Building Services (NI) Limited | Construction | 2019 |
| Victoria Road Land Management Ltd | Extraterritorial | 2002 |
| Village Green Residents Limited | Extraterritorial | 1988 |
| Viscount Lane Apartments Management Ltd | Extraterritorial | 2013 |
| Volunteer East Africa Limited | Administrative & support | 2016 |
| VW Audi Auto Centre Ltd | Wholesale & retail | 2016 |
| VW Audi Auto Sales Ltd | Wholesale & retail | 2024 |
| W D Buckley Associates Limited | Professional & scientific | 2011 |
| W J Scarlett & SON Limited | Wholesale & retail | 2018 |
| W.A.Ross & Sons Limited | Manufacturing | 2019 |
| W.J. Blair Accident Repairs Ltd | Wholesale & retail | 2014 |
| Walker Real Estate Ltd | Real estate | 2024 |
| Walker Transport (Ireland) Limited | Transport & logistics | 2010 |
| Wallace Avenue Apartment Management Company Limited | Households | 2012 |
| Warwick Construction Company Limited | Extraterritorial | 1997 |
| Waste Collection Services Limited | Water & waste | 1973 |
| WCC Developments Limited | Construction | 2017 |
| WCC Rents Ltd | Extraterritorial | 2017 |
| Wearesurge Limited | Professional & scientific | 2025 |
| WEE Maisie's Ltd | Wholesale & retail | 2020 |
| Welcome Nest Properties Ltd | Real estate | 2025 |
| Westbury Apartments Ltd | Extraterritorial | 2004 |
| Westbury Land Management Limited | Extraterritorial | 2001 |
| Westbury Townhouse Management Ltd | Extraterritorial | 2004 |
| Westfort Management Company Limited | Extraterritorial | 2006 |
| Westingmouse Signalling Limited | Professional & scientific | 2024 |
| Weztranz Storage Ltd | Transport & logistics | 2024 |
| Weztranz Ltd | Transport & logistics | 2011 |
| WGH Consultants Ltd | Professional & scientific | 2024 |