The government authorized the "special pay" in 2009 following criticism from some troops and Congress who said the "stop loss" policy that extended enlistments amounted to a "back door draft." Most of the troops fought in Iraq and Afghanistan.
The Army has paid $245 million in bonuses for 84,000 soldiers since the law passed, said Army Maj. Roy Whitley, who is managing Army efforts to provide the special pay.
The Army has yet to pay up to $160 million to 57,000 current or former soldiers, or to families of those who have died or were killed while on stop-loss. That includes 22,000 requests that are currently under review and about 35,000 people the Army cannot yet locate.
The Army used stop-loss extensively to maintain troop levels as fighting in Iraq ramped up. Other services also used the program, but less frequently.
There are about 15,000 unpaid cases among other services, the Pentagon says.
The military has ended the practice of stop-loss.
Congress passed a law in 2009 to compensate the troops with retroactive bonuses of $500 for every month served beyond enlistment. The average payout is about $3,800.