List of monarchs in Britain by length of reign

The following is a list, ordered by length of reign, of the monarchs of the United Kingdom of Great Britain and Northern Ireland (1927–present), the United Kingdom of Great Britain and Ireland (1801–1927), the Kingdom of Great Britain (1707–1800), the Kingdom of England (871–1707), the Kingdom of Scotland (878–1707), the Kingdom of Ireland (1542–1800), and the Principality of Wales (1216–1542).

Queen Elizabeth II became the longest-reigning monarch in British history on 9 September 2015 when she surpassed the reign of her great-great-grandmother Queen Victoria.^[1][2] On 6 February 2017, she became the first British monarch to celebrate a Sapphire Jubilee, commemorating 65 years on the throne. On 6 February 2022, Elizabeth II became the first British monarch to reign for 70 years, and large-scale celebrations for her Platinum Jubilee occurred on 2 to 5 June. Later that year, Elizabeth II died at the age of 96, after reigning for 70 years and 214 days.^[3]