This depends on the size of your baby. If you are questioning, give it a try! To test, see our video on how to change from narrow seat to wide seat here. Fit check: baby's legs should be supported from knee to knee and legs should be able to bend freely at the knee joint. Ensure your child's legs are bent at a 90 degree angle once in the wide seat setting. If baby's legs are still extended (even slightly!) at the knee once in the wide seat, baby is not quite ready. Wait another few weeks to a month for baby to grow a bit more and try again!