She donned a demure pale yellow coat-dress by Alexander McQueen as she arrived at St George’s Chapel earlier this morning.
A Kensington Palace statement said: “Her Royal Highness, The Duchess of Cambridge will be wearing a primrose yellow wool silk tailored coat by Alexander McQueen.
“The Duchess of Cambridge is wearing a hat designed by Philip Treacy and shoes by Jimmy Choo.”
This is the first appearance the 36-year-old has made since welcoming Prince Louis on April 23 at St Mary’s Hospital in London.
The Duke and Duchess’s third child, who is just under a month old, did not attend the Royal Wedding.
It is believed the tot remained behind at Kensington Palace.