Prime Minister of the United Kingdom

The prime minister of the United Kingdom is the head of government of the United Kingdom. The prime minister advises the sovereign on the exercise of much of the royal prerogative, chairs the Cabinet, and selects its ministers. Modern prime ministers hold office by virtue of their ability to command the confidence of the House of Commons, so they are invariably members of Parliament. The office of prime minister is not established by any statute or constitutional document, but exists only by long-established convention, whereby the monarch appoints as prime minister the person most likely to command the confidence of the House of Commons. In practice, this is the leader of the political party that holds the largest number of seats in the Commons. The prime minister is ex officio also First Lord of the Treasury (an office often associated with the premiership between 1721 and 1895, after 1902 always united to it, and, after 1905, an official title of the position), Minister for the Civil Service, the minister responsible for national security, and Minister for the Union. The prime minister's official residence and office is 10 Downing Street in London. Early conceptions of the office of prime minister evolved as the primus inter pares ("first among equals"); however that does not differentiate on status and responsibility upon whoever is holding office. Historically, the prime minister was the first amongst equals, until 1868. Since then, that characterisation of the prime minister has changed to be reflective of the democratic nature of their position, but also their heightened importance. The power of the prime minister depends on the support of their respective party and on the popular mandate. The appointment of cabinet ministers and granting of honours are done through the prime minister's power of appointment. The prime minister alongside the cabinet proposes new legislation and decides on key policies that fit their agenda which are then passed by an act of parliament. The power of the office of prime minister has grown significantly since the first prime minister, Robert Walpole in 1721. Prime ministerial power evolved gradually alongside the office itself which have played an increasingly prominent role in British politics since the early 20th century. During the premierships of Margaret Thatcher and Tony Blair, prime ministerial power expanded substantially, and their leaderships in the office were described as "presidential" due to their personal wielding of power and tight control over the cabinet. The prime minister is one of the world's most powerful political leaders in modern times. As the leader of the world's fifth largest economy, the prime minister holds significant domestic and international leadership, being the leader of a prominent member state of NATO, the G7 and G20. As of 2025, 58 people (55 men and 3 women) have served as prime minister, with the first, Walpole, taking office on 3 April 1721. The longest-serving prime minister was also Walpole, who served over 20 years, and the shortest-serving was Liz Truss, who served seven weeks. Keir Starmer succeeded Rishi Sunak as prime minister on 5 July 2024, following the 2024 general election.