Mignolet first represented the Belgian under-21 side in 2008, and went on to make ten appearances for the side. On 1 September 2010, he won his first call up to the Belgian senior squad after a good run of form for Sunderland. He made his full international debut in a 2–0 victory over Austria on 25 March 2011 in a UEFA Euro 2012 qualifying match. He remained in the starting line-up for each of the four remaining qualifying matches, in addition to playing in three friendly matches during the qualifying campaign. However, he was unable to help Belgium qualify for the Euro 2012 finals, as a 3–1 defeat against Germany saw them finish third in their qualifying group.