Confidence motions in the United Kingdom in the context of "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.

The Fixed-term Parliaments Act 2011 (c. 14) (FTPA) was an act of the Parliament of the United Kingdom which, for the first time, set in legislation a default fixed election date for general elections in the United Kingdom. It remained in force until 2022, when it was repealed by the Dissolution and Calling of Parliament Act 2022. Since then, as before its passage, elections are required by law to be held at least once every five years, but can be called earlier if the prime minister advises the monarch to exercise the royal prerogative to do so. Prime ministers have often employed this mechanism to call an election before the end of their five-year term, sometimes fairly early in it. Critics have said this gives an unfair advantage to the incumbent prime minister, allowing them to call a general election at a time that suits them electorally. While it was in force, the FTPA removed this longstanding power of the prime minister.

Under the FTPA, general elections were automatically scheduled for the first Thursday in May of the fifth year after the previous general election, or the fourth year if the date of the previous election was before the first Thursday in May. However, the FTPA also provided two ways to call an election earlier. One was a Commons vote of no confidence in the government, which still required only a simple majority of voters. The other was a vote explicitly in favour of an earlier election, which required a qualified majority of two-thirds of the total membership of the Commons. The first election under the FTPA was held on 7 May 2015. An early election was held in 2017, after Prime Minister Theresa May received approval to call it by a two-thirds majority.