The Conservative leadership contest is under way, with nominations now open.

Rishi Sunak officially stood down after leading the Tories to their worst performance at a general election, but is staying on as acting leader until his replacement is chosen.

That person will be the sixth Tory leader in less than eight and a half years.

Each candidate needs the support of at least 10 MPs to get on to the ballot, including a proposer and seconder. MPs can nominate only one candidate per voting round.

This is a much lower bar than during the last leadership election in 2022, when hopefuls needed the backing of 100 MPs. Mr Sunak was the only one to enter the race with that level of support, and so became the party leader.

There are currently 121 Tory MPs but those who are also whips, or sit on the executive of the backbench 1922 committee, cannot nominate a candidate.

Therefore a maximum of 10 candidates could meet the threshold, though the eventual number is likely to be lower.

A three-month campaign will begin when nominations close on 29 July.

When Parliament returns from summer recess in early September, a number of rounds of voting among Conservative MPs will reduce the field to an expected four leadership hopefuls.

In each round, the candidate who finishes last will be eliminated.

‘Beauty parade’

The final four will be given a chance to speak directly to Conservative members at the party’s conference between 29 September and 2 October.

Precise details of this “beauty parade” have yet to be announced.

After the conference, the remaining candidates will be reduced to two in a final round of voting by MPs and those two will be put to a ballot of party members.

Party members’ vote

If two candidates remain at the end of these ballots of MPs , members of the Conservative Party will choose the next leader in a vote in the days leading up to 31 October.

Party members will make their choice via secure online voting, though this system has previously been criticised for its susceptibility to hackers and rogue state interference.

In recent years, party members have tended to pick the more right-wing candidate of the final two. In the first of the 2022 leadership elections, Mr Sunak consistently won more support from MPs than Liz Truss during each round until party members had their say.

To be eligible to vote, party members must have been active for 90 days before the ballot closes and must have been party members when nominations opened.

New leader chosen

The new leader of the Conservative Party will be announced on 2 November – at which point Mr Sunak will hand over the reins.

The winner will become the official leader of the opposition and the figurehead of the Conservatives’ efforts to rebuild the party.

So far, five MPs have announced they will run: shadow home secretary James Cleverly, former Home Secretary Dame Priti Patel, shadow security minister Tom Tugendhat, ex-Housing Secretary and immigration minister Robert Jenrick, and shadow work and pensions secretary Mel Stride.

Other potential candidates include former Home Secretary Suella Braverman and shadow housing, communities and local government secretary Kemi Badenoch.

Shadow health secretary Victoria Atkins ruled herself out of the race. Announcing her decision in a social media post, she said she wanted to help the next leader “rebuild and renew our party”.