“When the curtain falls, it’s time to get off the stage.” So said John Major the morning after the 1997 election, announcing his resignation as Tory leader. But he actually remained leader for another 6 weeks. This was typical of Tory leaders, who have universally remained in post while their leader is chosen.

This has remained the case after the change to include the final members ballot, stretching the timetable. Even Liz Truss waiting for Sunak to be chosen by MPs, extending her leadership by 11% in doing so. It is unknown for a Tory leader to quit and leave a caretaker in charge for the replacement process.

So how long will that process take? Probably a good couple of months, history suggests.

Since the members ballot was added to the process by William Hague, the Tories have only completed a contested leadership election in under a month once – when May’s opponents all dropped out one after another in 2016.

Departing Leader and Year	Contested Election?	Duration of Election
Hague, 1997	Yes	98 days
Iain Duncan Smith, 2003	No	1 day
Howard, 2005	Yes	61 days
Cameron, 2016	Yes, but no member’s ballot	13 days
May, 2019	Yes	47 days
Johnson, 2022	Yes	55 days
Truss, 2022	No	1 day

Assuming the party is out of office post-election, there will be no reason or pressure to expedite the process and I suspect candidates will go all the way to the members. If so, the process is likely to take at least 50 days or so. The question of Sunak’s departure date then simply becomes when will the election be.

Counting backwards from New Year’s Eve, any election after 12 November would leave less than 50 days until 2025. Coincidentally, the date recently rumoured by many journalists as being pencilled in is 14 November. The betting on Sunak’s departure therefore boils down to if you think he will call the election before mid-November or not, with a bit of wiggle-room in those numbers for the process being slower over Christmas or conversely the party deciding to speed it up on this occasion.

I suspect he will wait until near winter to go to the polls and not be replaced until 2025. While an earlier election is possible, history tells us that parties well behind in the polls tend to wait to the very last minute to call elections. The timing does seem close, however, and while I have recently been backing a 2025 departure I might switch to 2024 if the odds move too much further. It could easily be a matter of days either side.

Regarding edge cases, a few other things to note:

• If Sunak somehow wins the election, most bookies are offering odds on his departure being ‘2025 or later’, so those bets should still win;
• If Sunak does buck the trend and resign immediately as leader, most bookies are offering odds on him being ‘Permanently replaced’ as leader. But make sure you read the market name/terms carefully; and
• If you backed my tips last year there is a possibility of covering both angles, since bookies have largely moved from ‘Departure Date as PM’ markets to ‘Departure Date as Leader’. If you backed 2024 in the PM option and now back 2025 in the Leader option (if you can get evens or close both times) you would have a low risk book with a very plausible prospect of winning both sets of wagers.

For now, I’ve been loading up on ‘2025 or later’ bets but wouldn’t go much lower than evens on it (Ladbrokes at 5/6 is the best price I’m aware of right now). Ultimately the election date is in the gift of one man, and the timing based on likely election dates is pretty tight for the new year.

Pip Moss posts on Political Betting as Quincel. He has bets on Rishi Sunak leaving office as PM in 2024 at average odds of just over evens and bets on Rishi Sunak being replaced as Tory leader in 2025 or later at average odds of evens. You can follow him on Twitter at @PipsFunFacts or BlueSky at @Quincel.Bsky.Social

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