The current polls suggest that many voters who backed the Conservatives in 2019 will switch to Labour in the next election, leaving seats previously won comfortably by the Tories at risk. Combining constituency results from 2019 with current polls, Guardian analysis can estimate which Conservative seats are the most vulnerable and which household names might lose their seats.
Many Conservative MPs have already said they are not standing in the next election, including Kwasi Kwarteng, Dominic Raab, Matt Hancock and Sajid Javid. But if current polling holds true some big names could be set to leave parliament, such as Iain Duncan Smith in Chingford and Woodford Green, who has a majority of three points. Some Tories are in safe seats: a massive swing of 24.5 percentage points would be required to flip Priti Patel’s majority of 49 percentage points in her Essex seat of Witham, for example. Suella Braverman in Fareham and Waterlooville is also currently safe, with a swing of 21 percentage points needed to overcome her majority of 42 points. To understand the connection between swing and majority, it is important to remember that a swing from the Conservatives to Labour has a powerful double effect: Labour win votes, and the Conservatives lose them. That is why swing can overturn a majority of double its size. The table below shows the Conservative-held seats that are most at risk with the direct swing to Labour that the polls are currently indicating. This Guardian analysis assumes that direct swing will be applied uniformly across the country, regardless of local or other factors that would influence voting behaviour on election day, and excludes the impact of third parties.
These seats are the new constituencies in which the new general election will be fought, after the latest constituency boundary review. Labour has a steep hill to climb from its 2019 result if it wants to win the election and this analysis demonstrates how crucial it is for the party to persuade people who voted Tory in the last election to back Labour. Convincing voters to switch allegiance from the Conservatives directly to Labour can be more effective than focusing on winning votes from third parties. This interactive explains why that is.
Methodology Polling: Our poll numbers are taken from the Guardian’s poll tracker. This uses a unweighted 10-day rolling average of polls approved by the British Polling Council and where possible, excludes respondents who said they don’t know how they will vote. New constituency boundaries: UK constituency boundaries were changed in 2023, with constituencies changing size, name or ceasing to exist. To make the 2019 results a meaningful comparison for 2024, we are using the results of the 2019 election reprojected on to the new boundaries, giving an indication of the results as they would have been if that election had been run on the current boundaries. This piece explains the new constituency boundaries and allows you to find your new seat. Direct swing: For the purposes of this article we are assuming uniform national swing — that changes at a national level will be played out in the same way across all constituencies. This is a simplified model that does not account for variation in individual constituencies or the effects of other parties. The calculation behind direct swing, based on current polling numbers, is as follows: Find the change between Labour and the Conservatives’ vote share in 2019 and their predicted 2024 vote share, according to the latest polls. Add these two numbers together and divide them by two. If Labour went up 10 and Conservatives went down 15, that would be 10+15 / 2, indicating a swing of 12.5 points. We know the swing is in Labour’s favour because Labour is up and the Conservatives are down.