DeMelo, 26, was a part of the trade package Ottawa received from the San Jose Sharks in the Erik Karlsson deal. The pending UFA carries a cap hit of $900K this season.
The blue-liner has played well with the Senators, chipping in 10 assists in 49 games while averaging 19:55 of ice time. In his first season in Ottawa last year, he managed four goals and 22 points in 77 games.
Ottawa now owns two first-round picks, three second-round picks, and two third-round picks in the upcoming draft.