Byrne ya shiga Westlife tare da Kian Egan, Mark Feehily, Shane Filan da Brian McFadden. Byrne ya bayyana a cikin Westlife: Labarinmu cewa yana so ya canza sunan ƙungiyar zuwa West High; amma sauran sun fi son Westlife. Tare da Westlife, Byrne yana da 25 saman goma UK singles, 14 daga cikinsu, sun kasance lamba daya, 7 lamba daya albums kuma sun sayar da sama da miliyan 55 a duniya. An tabbatar da cewa Westlife sun sayar da miliyan 20.2 da bidiyo a Birtaniya a tsawon shekaru 14 da suka yi aiki <unk> miliyan 6.8 na waƙa, miliyan 11.9 da miliyan 1.5 na bidiyo. Byrne kuma yana da lambar ɗaya a Ireland a shekara ta 2002, tare da 'yan wasan kwallon kafa na Jamhuriyar Ireland da kuma Dustin Byrne wanda ya shiga gasar cin kofin duniya na 2002 na FIFA. "Ya zo tare da Westlife: Ya rubuta tambayoyin da yawa na Jamus da Ireland".
Kian Egan, Mark Feehily, Shane Filan da kuma Brian McFadden