User blog comment:RoyallyBella/Official Season 6 discussion blog/@comment-5875378-20150828202736

Winx Club is going to resume airing on Nick Jr. on September 9, 2015 at 6:00 pm EST with season 6 episode 18 "The Magic Totem".

Source: http://tvschedule.zap2it.com/tvlistings/ZCSGrid.do?fromTimeInMillis=1441598400000&stnNum=19211&channel=82&sgt=grid&aid=tvschedule

LocateTV does not have it listed yet but they do a poor job of updating it.