From 2000 to 2008, Stefán competed in nine international competitions for Iceland: five times at the Chess Olympiad (2000, 2nd reserve board; 2002, reserve board; 2004, 2nd reserve board; 2006, reserve board; 2008, board 4) and four times at the European Team Chess Championship (2001, board 4; 2003, board 3; 2005, board 2; 2007, board 4). His overall Olympiad score was 23/41 (+18–13=10), and his overall European Team Championship score was 16½/32 (+11–10=11). Iceland's best Olympiad result with Stefán on the team was 22nd in 2002, and their best European Team Championship result was 20th in 2001 and 2007.