Clarkson is currently a mentor on the singing competition series. Hudson coached contestants in Season 13 and also appeared in two seasons of the British version The Voice.
"We are so excited to welcome back Kelly and Jennifer, two dynamic forces who bring undeniable soul, passion and inspiration as coaches," Paul Telegdy, president of NBC Entertainmnet's alternative and reality group, said in a statement Thursday. "They each have a unique understanding of what it's like to be in the artists' shoes. Bringing these two voices together with Blake and Adam for Season 15 is sure to make this one of our best seasons yet!"
Hudson also posted a video of Clarkson enthusiastically announcing their returns.
"Girls against the boys, y'all," Clarkson said in the clip. "Team J. Hud. Team KC. We're coming after you, Adam and Blake. We're friends, but we're future frenemies."