Suresh Sriskandarajah, who pleaded guilty in July to conspiring to provide material support to the Tamil Tigers, has already been in custody for about 10 months.
Prosecutors in Brooklyn, N.Y., had wanted Sriskandarajah, known as "Waterloo Suresh," to serve the maximum sentence of 15 years, while he had argued for time served.
The 32-year-old, who earned university degrees in Waterloo, Ont., was arrested in 2006 along with Piratheepan Nadarajah, of Brampton, Ont., and freed on bail three years later before his extradition to the U.S. in 2012.
While in Canada, Sriskandarajah helped research and acquire aviation equipment, submarine and warship design software, night vision equipment and communications technology for the Tamil Tigers.
Nadarajah is to be sentenced on Jan. 31, 2014, after admitting earlier this month to conspiring to acquire anti-aircraft missiles and attempting to provide material support to a foreign terrorist organization.
Several co-conspirators have also been convicted of terrorism offences.
Last year an Ontario man was sentenced to time served for his role in the group. Ramanan Mylvaganam — a computer engineering student at the University of Waterloo — pleaded guilty in the U.S. to conspiring to provide material support to a foreign terrorist organization.
The arrests followed a joint investigation by the FBI and the RCMP into an alleged plot to buy weapons, launder money through front charities and smuggle equipment to the rebel group.
The Tamil Tigers, notorious for suicide bombings and political assassinations in their fight for an independent homeland in Sri Lanka, were declared a terrorist organization by the U.S. in 1997 and by Canada in 2006.