The 24-year-old defenseman had eight points (two goals, six assists) in 60 games with the Panthers last season. He was a restricted free agent who had an arbitration hearing scheduled for July 30.
"[MacKenzie] is a versatile, young two-way defender who made big strides in his development during his rookie season," Panthers general manager Dale Tallon said. "We're excited about keeping our group of talented young players together after their contributions to our strong finish last season. We look forward to watching our club build from that success this coming season and for years to come."
Selected by Florida in the seventh round (No. 206) of the 2013 NHL Draft, Weegar has eight points in 63 regular-season games.
