The Duke and Duchess of Sussex and Duke and Duchess of Cambridge will be among the guests at a celebration to mark the 50th anniversary of the Investiture of the Prince of Wales.
Charles' commitment to his Welsh patronages and charities will be honoured at the Buckingham Palace event hosted by the Queen, which will feature guests representing the charitable organisations he has supported over the decades.
The Welsh band the Stereophonics, who were supported by the Prince's Trust in their early days, will also be at the event as will Games Of Throne star Owen Teale.
Also among the guests will be the Duchess of Cornwall, the Princess Royal - and Justin Welby, the Archbishop of Canterbury, will give a speech.
Charles became the Prince of Wales aged nine, on July 26, 1958 and was formally invested with the title by the Queen on July 1, 1969 at Caernarfon Castle.
The investiture regalia worn by the heir to the throne will be on display, including the investiture coronet, sword, ring and rod, as well as the Letters Patent for the creation of Charles as Prince of Wales in 1958.
The reception will culminate with a musical performance in the palace ballroom by students from the Royal Welsh College of Music and Drama, which Charles supports as patron.
The performance will include a new piece written for the anniversary by Welsh composer Paul Mealor, inspired by the legend of the Lady of Llyn y Fan Fach, a mountain lake near the prince's Welsh home, Llwynywermod in Carmarthenshire.