The 38-year-old signal caller released a statement through his agent saying that he still has the desire to play, but is no longer willing to commit to the preparation needed to do so.
Collins was selected fifth overall in the NFL draft by the Panthers in 1995 after playing at Penn State.
In just his second season with the team, he led them to the NFC Championship game, where they lost to the Green Bay Packers.
He maintained a 55.8 completion percentage throwing for 40,441 yards, and 206 touchdowns in 195 career games.
Along with playing for the Panthers, Collins also spent time with the New Orleans Saints, New York Giants, Oakland Raiders, and for the last five years the Tennessee Titans.