Cape Town - Prince William and Kate’s baby will be called Prince George Alexander Louis of Cambridge.
The new British prince, who made his first public appearance on Tuesday, was born at St Mary’s Hospital on Monday.
Prince George follows his father as the third in line to the throne.
George has been the name of six British kings. The last, George VI, was the father of Queen Elizabeth and reigned from 1936 to 1952.
The name was a favourite of British bookmakers in the run-up to the announcement.
After his release from hospital images of the prince, his little hand peeking above a white crocheted wrap, blanketed the front pages of newspapers on Wednesday.
The Daily Mail offered a photo album image with the headline "Baby's first royal wave".