The King has knocked the Princess Royal off the top spot as the hardest working royal of the year, despite still undergoing cancer treatment.
Charles, 77, clocked up a total of 532 engagements over the last 12 months, 50 more than his sister, Princess Anne, who often takes the hardest-working title, according to research conducted by royal expert Patricia Treble for The Mirror, which included engagements up until 18 December.
As well as engagements across the UK, the King has also travelled abroad to Poland, Canada, Italy and Vatican City.
While Anne, 75, took second place with 478 engagements, the Duke of Edinburgh, 61, was third with 313 and his wife, the Duchess of Edinburgh, 60, with 235.
The King's siblings have travelled all around the world this year, with the Princess Royal visiting South Africa, Ukraine where she met President Zelensky, Australia where she celebrated the 100th anniversary of the Royal Australian Corps of Signals as its Colonel-in-Chief and Singapore to mark to 60 years of relations with the UK.
Among their many solo trips, Prince Edward and Sophie have visited Nepal and Japan together.
Queen Camilla, 78, is the fifth hardest-working royal with 228 engagements, followed by the late Queen's cousin, the Duke of Gloucester, 81, who has notched up 212.
According to the research, the Prince of Wales, 43, carried out 202 engagements in 2025, with the future King visiting troops in Estonia in March and travelling to Vatican City for Pope Francis' funeral in April.
In June, Prince William flew to Monaco to attend the Blue Economy and Finance Forum, and in July, he attended the Lionesses' matches during the Women's Euro 2025 in Switzerland, with the royal accompanied by his ten-year-old daughter, Princess Charlotte, for the final against Spain.
William's final overseas visit of the year was to Rio de Janeiro in Brazil for his annual Earthshot Prize Awards ceremony, which aims to find solutions to repair the planet.
Meanwhile, the Duchess of Gloucester, 79, carried out 113 engagements this year, followed by the Duke of Kent, 90, who racked up 77, and finally, the Princess of Wales, 43, with 69 engagements.
Kate announced at the beginning of the year that she is in remission from cancer and has made a gradual return to her public duties. While she has not travelled overseas this year, she has played major roles at all three state visits for the French, US and German Presidents.
The Prince and Princess of Wales were deployed to greet each of the three leaders first during their respective state visits, showcasing their growing responsibilities on the world stage.