The winner of the Conservative leadership race will also become prime minister, since the party has a majority of seats in the House of Commons. The next general election is due to be held in May 2020, unless exceptional circumstances lead to an early election.
Here is everything you need to know about the candidates.
Theresa May, 59, is from Eastbourne, Sussex. Educated at Oxford University, she became a member of Parliament (MP) in 1997 and was home secretary for six years. She is perceived as experienced and serious, but her support for the campaign to remain in the E.U. could damage her chances with those who voted for the UK to leave. She has been backed by a number of senior MPs and is widely seen as the frontrunner.
Michael Gove, 48, was born in Edinburgh and grew up in Aberdeen, Scotland. Educated at Oxford University, he was a journalist and became an MP in 2005. He was also a controversial, arguably unpopular, education secretary, due to of a number of reforms he sought. In 2015, Gove was promoted to serve as Lord Chancellor and Secretary of State for Justice. He was a leader of the campaign to leave the E.E. and has said several times he would did not think he is prime minister material. Gove has presented himself as the "candidate for change."
Andrea Leadsom, 53, is from Aylesbury, Buckinghamshire. Educated at Warwick University, she was elected in 2010 after a long career in banking and finance. The energy minister was a strong Leave campaigner in the referendum on whether to remain in or leave the E.U. In presenting her bid to become prime minister, the former businesswoman, who has the support of a number of senior MPs, said she knows how to overcome prejudice in a male-dominated world. Referencing the vote to leave the E.U., Leadsom said the country had not as some people may claim "lost our senses, we have just rediscovered our freedom."
Liam Fox, 53, from East Kilbride, studied at Glasgow University. He was a general practitioner doctor and army medical officer before he was elected to Parliament in 1992. While he has vast experience in Parliament and is a known E.U. opponent, he is also seen as the disgraced former defense secretary whose career was cut short due to a row over lobbying in 2011. Fox, who was pro-Brexit in the referendum campaign, previously ran for the party leadership in 2005 and came in third. In launching his campaign, Fox said the leadership contest was not "Britain's Got Talent" and played up his experience.
Stephen Crabb, 43, was born in Inverness and grew up in Pembrokeshire, Wales. He studied at Bristol University and London Business School before being elected MP in 2005. While he is perceived as an advocate for remaining in the E.U., he is appreciated for his background and ability to connect to poorer communities. He was promoted to the position of work and pensions secretary in March. He has spoken of the need to bring the UK together, promising to heal the "bad blood" in his party. Crabb launched his bid for prime minister on a joint ticket with Secretary of State for Business, Innovation and Skills Sajid Javid, who would become his chancellor. The pair have pledged a Growing Britain Fund of £100 billion ($133 billion), expected to finance projects such as flood defenses and national fiber-optic broadband networks.
To select their leader, 330 MPs will be voting in a series of secret ballots every Tuesday and Thursday starting this week, until the list of candidates is down to two. The winner is expected to be announced on September 9 after a vote between the two final candidates by the party's 1922 Conservative Party members.