When is the royal baby due? New role: If the baby's due in April, that means it was probably conceived in August (Image: Getty) The royal baby is expected towards the end of April 2015 - reportedly on the 25th. At the end of last year, a full statement from the Royal Family read: Their Royal Highnesses The Duke and Duchess of Cambridge are delighted to confirm they are expecting a baby in April 2015. The Duchess of Cambridge continues to be affected by Hyperemisis Gravidarum, but her condition is steadily improving..