General election: Labour would need record swing to win

The Labour Party would need a record swing in votes at the next general election to win a majority in the House of Commons, according to analysis of the new electoral map.

The next election will be fought on new constituency boundaries, redrawn to reflect population changes and to try to even out voter numbers in each area.

An analysis of these changes for BBC News, ITV News, Sky News and the Press Association suggests Labour needs a national swing of 12.7% to win with just a small majority.

That’s considerably higher than the 10.2% achieved by Tony Blair in 1997 and higher even than the 12% achieved by Clement Attlee in 1945.

The swing from the Conservatives to Labour would need to be uniform, to follow the same pattern everywhere, with other parties seeing no change in performance since 2019.

In practice, the picture will be more complicated, so this is a rough guide. But a uniform national swing has been a reliable model for general elections in the UK over a long period of time.
Boundaries changed

Changes to the political map ahead of the next general election mean constituencies will be new or different from the last general election for millions of people.

The boundary changes could have an impact on who becomes the local MP and which party wins the UK’s election overall.

You can use our tool to find out which constituency you are now in.

It will also give you an estimate of what the result would have been had these new boundaries been in place at the last general election, in 2019.

The research – by election experts Colin Rallings and Michael Thrasher along with David Denver in Scotland and Nicholas Whyte in Northern Ireland – also reveals which seats are likely targets for the main parties at the next election.

Under the changes, some constituencies will become safer for the party that holds them; others will become more at risk.

For example, Labour’s shadow chancellor Rachel Reeves won her Leeds West constituency with a healthy majority of 10,564 over the Conservative candidate in 2019.

Next time that will be the newly-drawn Leeds West and Pudsey seat, with a slimmer “notional” majority of 2,963.

The seat of Ben Wallace, Conservative MP and former defence secretary, was abolished in the changes. He will stand down at the next election.

Chancellor Jeremy Hunt will contest the new constituency of Godalming & Ash after his old South West Surrey seat was split in two.

Notional figures are an estimate of what the result would have been if everyone voted in the same way as they did in 2019. The estimate draws on local election results in individual council wards over several years.

It is a rough guide – but it is all the parties have to go on when they are deciding where to focus campaigning. They have to identify the “target seats” where they have a realistic chance of making gains.