Kate will give birth – if all goes to plan – naturally in the Lindo wing of St Mary's Hospital in Paddington. It is the same private wing where Prince William was born 31 years ago.
It had been rumoured the Palace would release a statement, or even tweet the news, but the Royal Baby's arrival will be announced on a formal notice placed on an easel in the forecourt of Buckingham Palace.
It will be the same easel used to announce William's birth on June 21, 1982.
The announcement will be written on paper which will be carried by car from the hospital to Buckingham Palace with a police escort.
Following the formal announcement outside the Palace, a second announcement will reveal the baby's gender and weight.
The baby will be delivered by obstetrician Marcus Setchell, who has been gynaecologist to the Queen since 1990.
William is expected to take two weeks paternity leave from his job in the RAF, before returning to work.
A 24-hour 'normal delivery' at the Lindo wing costs a minimum of £4,965, and there are additional charges for more than one overnight stay.
Where Kate, Wills and the new arrival will stay immediately after their baby's birth remains unclear. Kate is said to want to head home to her mum and dad's house, while the Queen has invited the new family to stay at Balmoral.
Kate's due date is reported to be July 15. The couple do not know the sex of their baby, and will not find out until he or she makes their arrival.
Good luck Kate and Wills!