 His first cap for the Republic of Ireland national B team came on 20 November 2007 against Scotland.Whelan made his debut for the senior team against Serbia in May 2008 and scored his first international goal against Georgia in Mainz, Germany on 6 September 2008.Since the appointment of Giovanni Trapattoni, Whelan became a key member of the squad and made 11 straight appearances despite previously being considered an "also-ran".