As a 15-year-old Eichel represented the United States at the 2012 Winter Youth Olympics. He won a bronze medal with Team USA at the 2013 World U-17 Hockey Challenge and a silver medal at the 2013 IIHF World U18 Championships. The following season he helped the USA squad capture the gold medal at the 2014 IIHF World U18 Championships, and he competed as a 17-year-old as Team USA's youngest player at the 2014 World Junior Ice Hockey Championships. Eichel represented Team USA in the 2015 World Junior Ice Hockey Championship.