The coronation service lasted about two hours and involved various stages, including recognition, oath, anointing, investiture and crowning, followed by enthronement and homage.
At 12:02 p.m. (1102 GMT), Charles III was formally crowned as the Archbishop of Canterbury Justin Welby placed St Edward's Crown onto the head of the monarch. The congregation sang a hymn; bells at the historic church rang; trumpets sounded, and gun salutes were fired across the country to mark the moment.
King Charles III, 74, ascended to the throne in September last year following the death of his mother, Queen Elizabeth II.
Queen Camilla was also coronated on Saturday in a much simpler ceremony, as she was anointed and crowned with Queen Mary's Crown.
King Charles III and Queen Camilla will return to Buckingham Palace in procession after the service at Westminster Abbey, using the same route they took this morning in reverse, with thousands of spectators lining the streets.
The ceremonial events will conclude with the royal couple and members of the royal family watching a large formation fly-past on the balcony of Buckingham Palace in the afternoon.
