Prince Harry will wed US actress Meghan Markle on May 19 next year, Kensington Palace says.
The royal institution announced the news on Twitter.
The wedding will be held at St George's Chapel at Windsor Castle.
The couple announced their engagement last month after dating for 16 months.
The nuptials will take place on a Saturday, which is unusual for the royals. Prince Harry's brother, William, was married on a Friday.
The choice of day will quash hopes of many workers in Britain that an extra public holiday would be declared for the wedding day next Spring. The date is also the same as FA Cup Final day, arguably the UK's biggest football match of the year.
The date of the wedding comes only a month after Prince Harry's sister in law, Kate Middleton, is due to give birth to her third child with Prince William.
Other likely guests include Harry's dad Prince Charles and the Duchess of Cornwall.
The Queen hosts a traditional gathering every year at her Norfolk retreat, which includes presents and games on Christmas Eve.
On Christmas morning, they all go to a service at St Mary Magdalene Church on the estate.
The Queen often drives while other members of the family walk the short distance from the house to the church where a crowd of well wishers wait to greet them outside.
Last year Harry was at Sandringham along with Charles and Camilla and Wills and Kate.
His uncles Prince Andrew and Prince Edward and cousins Princess Beatrice and Princess Eugenie were also among the large family party.
- additional reporting news.com.au