- Charles, Prince of Wales
- United Kingdom ()
As of 14 January 2021, Charles, Prince of Wales (Charles Philip Arthur George) had been heir apparent to the British throne for 68 years 343 days.
The previous holder of this record was Charles's great-great-grandfather Edward VII, who finally took to the throne upon the death of Queen Victoria on 22 January 1901. Charles exceeded Edward's term as first in line of succession on 20 April 2011, when he had been heir-apparent for 59 years 2 months 14 days.
Prince Charles became heir apparent at the age of three when his mother, Princess Elizabeth, acceded to the throne on 6 February 1952. Edward VII became the heir apparent at birth on 9 November 1841 as his mother, Queen Victoria, was already on the throne.