A statement by Kensington Palace reads: "The following guests will attend Prince George's Christening today at the Chapel Royal, St James's Palace," followed by a very short guest list.
Prince George's great-grandmother the Queen and her husband Prince Philip will be in attendance, as will the baby's grandfather Prince Charles, his wife the Duchess of Cornwall, and baby George's uncle, Prince Harry.
CLICK ON PHOTOS FOR FULL GALLERY
Other immediate family to attend the intimate gathering includes Kate's parents Carole and Michael Middleton, and her brother and sister James and Pippa.
The only other guests at the christening of Great Britain's future King are, according to the statement, "Prince George's Godparents and their spouses."
Prince William's cousin Zara Tindall has been given the privilege of being Prince George's godparent, as has Julia Samuel, who was a close friend of William's mother Princess Diana.
The Duke and Duchess of Cambridge also opted for their trusted former private secretary who continues to serve part-time as principal private secretary and equerry, Jamie Lowther-Pinkterton and Earl Grosvenor, the son of the Duke of Westminster.
Close friends make up the rest of the six godparents, including William's childhood friend William van Cutsem, Kate's school friend Emilia Jardine-Paterson, and Oliver Baker, who went to university with both William and Kate.
Prince George's christening – a break in tradition by his parents in both choice of place and the limited number of guests – will be the first time the baby is snapped in official royal photographs.
For the occasion, the royal baby will wear a handmade replica of the royal christening robe, made by dressmaker to the Queen, Angela Kelly.
The Chapel Royal's lily font and water from the River Jordan will be used during the baptism.