While the rest of his family celebrated at Sandringham, Norfolk, William, wearing a suit, and Kate, in a burgundy winter coat, were at church 150 miles away.
The couple are staying with Kate’s family for Christmas Day. They turned up for the service at St. Mark’s Church with Kate’s sister Pippa and brother James.
At Sandringham, Queen Elizabeth was joined by most of her family, including Prince Charles and his wife Camilla, and Princesses Beatrice and Eugenie. Apache helicopter pilot Prince Harry is away, serving in Afghanistan.
The Queen, greeted by about 1,000 well-wishers, wore a turquoise coat and matching hat for the service.