This deferment is available in all three loan programs, FFEL, Direct and Perkins. It is available to military service members on active duty during a war, other military operation or national emergency, members of the National Guard called to active duty during a war, military operation or national emergency and reserve or retired members of the Armed Forces called to active duty during a war, military operation or national emergency.

This deferment may be granted based on a request from the borrower or the borrower’s representative. Borrowers or their representatives must submit a deferment form signed by an authorized official. Alternatively, the borrower may submit a copy of military orders or a statement from a commanding or personnel officer proving that the borrower is serving on active duty during a war, military mobilization, or national emergency.

There is no time limit on the military deferment. (The previous three year time limit was eliminated in 2007). The eligibility period ends 180 days after the borrower is demobilized from active duty service.

Some borrowers called to active duty will not be eligible for military deferments.  To help address this gap, there is a mandatory forbearance available to National Guard members who qualify for the post-active duty deferment (see below) , but do not qualify for a military or other deferment.

 

from: http://www.studentloanborrowerassistance.org/repayment/programs-for-military/