In the coronation message, Charles called the nation’s support throughout the historic celebrations “the greatest possible coronation gift”.
He promised that alongside his wife Camilla, they would rededicate their lives to serving the people of Great Britain and wider Commonwealth.
He said: “As the coronation weekend draws to a close, my wife and I just wanted to share our most sincere and heartfelt thanks to all those who have helped to make this such a special occasion.
“We pay particular tribute to the countless people who have given their time and dedication to ensuring that the celebrations in London, Windsor and further afield were as happy, safe and enjoyable as possible.
“To those who joined in the celebrations - whether at home, at street parties and lunches, or by volunteering in communities - we thank you, each and every one,” the King continued.
“To know that we have your support and encouragement, and to witness your kindness expressed in so many different ways, has been the greatest possible coronation gift, as we now rededicate our lives to serving the people of the United Kingdom, the realms and Commonwealth.”
In the newly released official photographs, Charles was captured in his full regalia - wearing the Imperial State Crown, holding the Orb and Sceptre with Cross, and dressed in his regal purple tunic and Robe of Estate, seated in the Throne Room.
Camilla was pictured alongside the King, and also in a solo portrait, wearing Queen Mary’s Crown, with the train of her lengthy embroidered Robe of Estate spread in front of her.
The working royal family - the Prince and Princess of Wales, the Edinburghs, the Princess Royal and Vice Admiral Sir Tim Laurence, the Duke of Kent, the Gloucesters and Princess Alexandra - were also photographed stood with the King and Queen in the images by Hugo Burnand.
It comes after new figures show the Coronation Concert on Sunday night was watched by an average of 10.1 million, overnight figures from the BBC show. The event had a peak audience of 12.3 million, the corporation said.
Kate Phillips, BBC Director of Unscripted, said: “Last night’s Coronation Concert was an unforgettable evening of spectacular performances that brought us all together in celebration.
“Against the stunning backdrop of Windsor Castle, the concert reflected many of the King’s passions and highlighted the outstanding talent we have in the UK and beyond.”
At the star-studded event on Sunday evening, Prince William paid tribute to the King’s coronation “pledge of service” as the newly crowned monarch’s life was celebrated.
William took to the stage during the Coronation Concert to speak about the pride he felt for his father, highlight Charles’ recognition of “people of all faiths, all backgrounds” and fondly remember his grandmother Queen Elizabeth II.
During a night of music staged in the grounds of Windsor Castle, actors, singers and entertainers came forward to praise the nation’s King - and Kermit the Frog managed to gatecrash the royal box.
William told the 20,000 spectators: “Pa, we are all so proud of you.” When he took to the stage he delighted his daughter Princess Charlotte, who could be seen pointing out her father to brother Prince George.
The future King made a poignant reference to his late grandmother Queen Elizabeth II, adding: “I know she’s up there, fondly keeping an eye on us.” He told Charles: “She would be a very proud mother.”
On Monday, William’s son Louis stole the show as he got stuck into a spot of painting, digging and decorating when he volunteered with his family helping renovate a Scout hut site in Slough, Berkshire, as part of the Big Help Out.
The five-year-old royal tried his hand at archery, making hand prints on a mural, and ended the day splashed with paint but got his reward - a smore, a marshmallow and chocolate sandwiched between two biscuits.
Kensington Palace said it was the youngster’s first royal engagement.
Although Louis has been at numerous big royal events from Trooping the Colour to the coronation, it is thought to be the first time he has actively participated in an official visit face to face with the public.
Meanwhile, the King and Queen had a quiet day away from the public eye after Sunday evening’s concert.