The King’s official birthday is taking place on the third Saturday in June, with the Trooping the Colour marking the British sovereign's special day.
His late mother Queen Elizabeth II’s official birthday usually took place on the second Saturday in June, in a tradition that has gone on for over 260 years.
Over 1400 parading soldiers, 200 horses, and 400 musicians come together each June in a great display of military precision, horsemanship and fanfare, with royal fanatics camping out for the occasion.
70 aircraft, including the Red Arrows, will fly through the skies over Buckingham Palace at around 13:00 BST, as senior royals watch on from the iconic balcony.
The Prince and Princess of Wales and their children will likely look on alongside the King and Queen.
However, Prince Harry and wife Meghan will not be in attendance.
This is King Charles III's first Trooping the Colour, just weeks after his coronation.
