The singer says she needs to get her health back on track.
Ke$ha has postponed her tour to spend longer in rehab.
The singer, who is being treated for an eating disorder, said that although she had been looking forward to touring, she needed to get her health back on track.
Initially, the singer had planned to stay for 30 days at a facility in Chicago. However, her tour dates for March and April have all now been postponed.
“I was so looking forward to performing at these dates but I need to follow my doctor’s advice and get my health back on track,” she said in a statement.
“All of your support during this time has been so amazing. I couldn’t have done this without you all. I look forward to coming back stronger than ever on the next tour.”