Experts from Genesreunited.co.uk have trawled the royal family's birth and marriage records for the past 100 years, and reckon The Duke and Duchess of Cambridge will welcome a son or daughter on 27th August 2013.
The team at Genesreunited.co.uk calculated that 852 days is the average period between a royal wedding and the arrival of a couple's first baby.
If these calculations are correct, we'd be expecting an announcement around March next year.
"There's certainly been a lot of speculation about when the arrival of a royal baby might be - the bookies are even taking bets on names,' said Rhoda Breakell, head of Genesreunited.co.uk.
The research team also reckon they have worked out possible name choices for Kate and Wills' first baby. Carole, Elizabeth, Mary, Philippa or Victoria for a little girl, and George, Henry, Charles, Michael or James for a boy.
What do you think? An August baby for Kate and Wills, or will Zara and Mike beat them to it?