List of British monarchs by longevity
This is a list of British monarchs by longevity since the Union of the Crowns of England, Scotland and Ireland in 1603.
To maintain consistency within the table, the dates of birth and death for each monarch are given in New Style.
Two measures of the longevity are given—this is to allow for the differing number of leap days occurring within the life of each monarch. The first column is the number of days between date of birth and date of death, allowing for leap days; the second column breaks this number down into years, and days, with the years being the number of whole years the monarch lived, and then days after his or her last birthday.
Queen Elizabeth II, the present British monarch (born 21 April 1926; Queen since 6 February 1952), is the longest lived British sovereign, at the age of 90 years, 300 days.
* As of 15 February 2017.
While Queen Victoria lived for only 4 days more than George III in terms of years and days format, she actually lived for five days more because there were 20 leap days during Victoria's life and only 19 leap days during the life of George III.
If Charles, Prince of Wales, were to accede to the throne, he would immediately be ranked 9th with an age of 68 years, 93 days. If his son, William, Duke of Cambridge, were to accede any time before September 2030, he would be ranked 18th.
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