2019 Conservative Party leadership election

The 2019 Conservative Party leadership election was triggered when Theresa May announced on 24 May 2019 that she would resign as leader of the Conservative Party on 7 June and as Prime Minister of the United Kingdom once a successor had been elected. Nominations opened on 10 June; 10 candidates were nominated. The first ballot of members of Parliament (MPs) took place on 13 June, with exhaustive ballots of MPs also taking place on 18, 19 and 20 June, reducing the candidates to two. The general membership of the party elected the leader by postal ballot; the result was announced on 23 July, with Boris Johnson being elected with almost twice as many votes as his opponent Jeremy Hunt.

Speculation about a leadership election first arose following the party's performance at the 2017 snap general election. May had called it in hope of increasing her parliamentary majority for Brexit negotiations. However, the Conservatives lost their overall majority in the House of Commons. Subsequent speculation arose from the difficulties May had in obtaining a Brexit deal acceptable to the Conservative Party. These increased in November 2018, with members of the Eurosceptic European Research Group pushing for a vote of no confidence in May; the forty-eight letter threshold to force a confidence vote was met in December 2018; however, May won the vote and remained in office. In early 2019, Parliament repeatedly voted against May's proposed deal, leading to her resignation.

The first members' vote leadership election of the Conservative Party was held in 2001, but since then the party had been in opposition during all leadership elections except in 2016, which concluded with Andrea Leadsom withdrawing before the members' vote. Johnson became the first Conservative Party leader elected by members to immediately assume the role of prime minister.