"I've made the very difficult decision not to return for another season," Spears said in a statement Friday. "I had an incredible time doing the show and I love the other judges and I am so proud of my teens but it's time for me to get back in the studio. Watching them all do their thing up on that stage every week made me miss performing so much! I can't wait to get back out there and do what I love most."
EW.com said Fox confirmed Spears' departure. Rumors have been swirling for weeks saying she would not return as a panelist on the show.
Reid, who has been a judge on the series since Season 1, has also said he does not plan to return next season.
No replacements for Reid or Spears have been announced yet.