Abdullahi Ahmed Abdullahi, 37, of Edmonton, Alberta, was extradited from Canada to San Diego in 2019, the Justice Department said in a statement.
Abdullahi pleaded guilty in a federal court in San Diego to all charges in December 2021, it said.
He was accused of aiding six North American nationals to travel to Syria, where they joined IS.
To help raise funds, Abdullahi admitted carrying out an armed robbery of an Edmonton jewelry store in 2014.
The six included three of his cousins from Edmonton, an 18-year-old cousin from Minneapolis and a San Diego resident, Douglas McAuthur McCain.
All six were subsequently killed fighting for IS, the Justice Department said.
Voice of America