Current reigning monarchs by length of reign

This is a list of currently enthroned monarchs sorted by length of service. It includes monarchs who do not reign over entire nations, such as Nazrin Shah of Perak, but does not include former monarchs and pretenders, such as Michael of Romania, ex officio monarchs such as François Hollande who in his capacity as President of France is also Co-Prince of Andorra, constituent monarchs such as the traditional African rulers, or monarchs whose position is unofficial, such as Tenzin Gyatso, 14th Dalai Lama.

Elizabeth II is the current longest-reigning monarch, having been Queen of Australia, Canada, New Zealand, and the United Kingdom since 6 February 1952. She is also the monarch of 12 other Commonwealth realms which have become independent states since 1952 and is therefore listed multiple times in the table below.

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