• TE Connectivity
• TIBCO Software
• TUI Group
• Tableau Software
• Takeda - Takeda Pharmaceutical Company Limited
• Talbot Group (Redwood Extended Care Facility)
• Tankardstown House
• Tata Consultancy Services
• Taylor Hopkinson
• Teckro
• Teleflex Medical Europe
• Temple Street Children's University Hospital
• Test Triangle
• The Abbey Group
• The Brehon Hotel
• The Butler's Pantry
• The Coca-cola Company
• The Connacht Hotel
• The Croke Park Hotel
• The Dean Hotel
• The Europe Hotel & Resort
• The Fitzwilton Hotel
• The Fruit People
• The Kingsley Hotel
• The Lake Hotel Killarney
• The Maritime Hotel
• The Metropole Hotel Cork
• The Montenotte Hotel
• The Morgan Hotel
• The National Maternity Hospital
• The National Orthopaedic Hospital Cappagh Designated Activity Company
• The Old Orchard Pub
• The Park Academy Childcare
• The Q Cafe Company
• The Recruitment Company
• The River Lee Hotel
• The Rose Hotel
• The SpitJack
• The Stars Group
• The Westbury Hotel
• The Works Stores
• Therapie Clinic
• Thorntons Recycling
• Three Q PERMS & TEMPS
• Three Steps Residential Assessment & Intervention
• Top Security Ireland
• Traditional Meat Company Ireland
• Tricel Ireland
• Trinity Care Nursing Homes
• Trinity City Hotel
• Tritech Engineering
• Twilio