There had been talk for some time now that Roberts was likely to be cut loose at some point, especially after they used they used their first-round pick on Josh Doctson.
Roberts, 28, was in the third year of his four-year, $16 million contract that includes $8 million guaranteed and set make a base salary of $4 million for the 2016 season.
According to OverTheCap.com, releasing Roberts will free up $3 million in available cap space while creating $2 million in dead money.
In 2015, Roberts appeared in nine games for the Redskins and catching 11 passes for 135 yards receiving and no touchdowns. He also contributed 231 kick return yards and a touchdown.