Ilsanker began his career in the youth squad of 1. Halleiner SK as goalkeeper but soon switched into the midfield. In 2005, he signed with Red Bull Salzburg, where he played in the Red Bull Juniors team.
On 4 April 2009, Ilsanker was called up to the first team bench for a league game. His first game for Red Bull Salzburg was a national cup match on 15 August 2009.[2] On 25 August 2009, he played his first international game for Red Bull Salzburg in the UEFA Champions League qualifier versus Maccabi Haifa.
At the end of the 2009–10 season Ilsanker signed with SV Mattersburg.[3] In 2012, he came back to Red Bull Salzburg. In the meantime, he was a regular of the starting team of the club. On 26 February, the club announced, that his contract was extended till 2018.
Stefan Ilsanker was sent-off on 19 December 2018 against Bayern Munich.[4]
On 31 January 2020, Ilsanker joined Eintracht Frankfurt on a deal lasting until 2022.[5][6] On 3 June 2020, Ilsanker came off the bench against Werder Bremen and scored twice in the final 10 minutes of the match to secure a 3–0 victory.[7]
On 23 June 2022, Ilsanker joined Italian club Genoa.[8]
He announced his retirement from football on 6 January 2024, after being without a club for six months following his release from Genoa.[9]
International career
Stefan Ilsanker with the Austria national football team, 2014
Ilsanker has won over 40 caps for Austria since his debut in 2014. Ilsanker represented his country at Euro 2016, where Austria finished last in Group F.[10] Ilsanker played in two matches for Austria at the tournament, their 0–0 draw with eventual champions Portugal[11] and 2–1 loss to Iceland.[12]
^"Erste Neuverpflichtungen bei Mattersburg" [First signings at Mattersburg]. UEFA.com (in German). Union of European Football Associations. 20 May 2010. Retrieved 9 May 2020.