Supernatural Season 5

Season Five is rumored to be the last season due to Eric Kripke's statement that he planned for the show to run for five seasons. Jensen Ackles has mentioned in an interview that at the time Season 4 would be the last but due to higher ratings they were signed on for a subsequent season. Despite this, Jared and Jensen have contracts for a Season 6, if the CW picks up the show for another season. The CW has since announced it's premiere schedule, setting Season five of Supernatural for release on September 10th. - Wiki Source