The Eagles are bringing back one of their fixtures at safety of recent seasons.
Allen, 26, has recorded 262 tackles and six interceptions in four NFL seasons. He has made 54 regular season starts in that span.
Malcolm Jenkins, whom the Eagles signed early in free agency from New Orleans, is likely to start at free safety next season. Allen, Earl Wolff (six starts in 2013), Chris Maragos and Keelan Johnson are the other safeties currently on the roster.