What is an exit poll and how do they work?

THE general election sees Brits head to polling stations or use postal votes to have a say in who they want in government.

A way of finding out who is likely to win the election before official results have been released is through an exit poll.

What is an exit poll?

Exit polls take place at around 133 polling stations across the country and those voting are asked to fill out a replica polling card after they have cast their real vote.

Tens of thousands of people are asked to fill out another polling card so these can be looked at before all votes have been counted.

This gives an indication as to how some people have voted, so may give an early indication as to which party is in the lead.

Fieldworkers from Ipsos Mori descend on the chosen polling stations to count up who could win.

Polling expert Sir John Curtice told the PA news agency: “Wherever possible we go back to the same places as last time. The method of the exit poll is that you compare the results in the selected polling stations this time, with the results of the exit poll last time.

How do exit polls work?

Identical ballots are used for exit polls, so it is like filling out your vote twice.

A replica ballot box is also used.

The reason for the same process is to encourage voters to carry out the exit poll as well as the main vote.

This is due to the process still feeling confidential rather than someone asking them who they have voted for.

What time are exit polls released?

Exit polls are released at 10pm which is also the latest time you can cast your vote and polling stations close.

This gives the current Prime Minister and other party leaders a snapshot as to how they are doing in the polls.

This is before the first results start to come in across the following hours.

Are exit polls accurate?

While a larger sample size and surveys at more ballot stations has improved the accuracy of the poll in the last few decades, it is still prone to making mistakes.

In 2015 it predicted a hung parliament, but David Cameron’s Conservatives squeezed over the line to a thin majority.

And in 1992 the poll famously predicted Labour leader Neil Kinnock would sweep into No.10 – yet John Major defied the odds to hold on to the keys for the Tories.

However, some have been way off the mark in the past.

For example, in 1974 the first British exit poll predicted a Labour majority of 132, but the actual majority was three.

But, in 2019, the exit poll predicted a Conservative majority of 86 seats, which was very close to the final 80-seat margin.

Sir John, professor of politics at Strathclyde University in Glasgow, said: “It’s tended to be relatively accurate, it’s not perfectly accurate, but there’s been a number of occasions in which it has ended up proving rather more accurate than what the opinion polls have been.