Three major television broadcasters have confirmed they will combine forces to release the same exit poll once voting ends on election night.
BBC News, ITV News and Sky News have announced that they will jointly publish the 2019 General Election exit poll at 10pm on Thursday.
It will be the fourth exit poll to be produced by the three broadcasters following similar exercises in 2010, 2015 and 2017.
Polling experts contracted to each channel will help to produce the results.
The poll will estimate the total number of Commons seats expected to be won by the Conservatives, Labour, the Liberal Democrats, the Green Party, the Brexit Party, SNP, Plaid Cymru, and others.
Professor Sir John Curtice, political commentator for BBC News, said: “The principal aim of the exit poll is to help viewers and listeners to navigate the initial hours of election night as the first results come in.
“By comparing the actual results with the forecast of the exit poll, we will be able to point to the political direction in which Britain is now apparently headed.”
Exit polls, based on interviews with people as they come out of polling stations, have in the past successfully predicted the exact outcome of general elections, even correctly working out the number of seats the major parties will win.
In 2017, audiences were shocked by the exit poll when it predicted a hung parliament, despite Theresa May’s Tories being ahead in the opinion polls throughout the campaign.
But the result bore out, with the Tories taking 317 seats – only three more than the exit poll predicted – and Labour taking 262, four fewer than estimated.
There have been mishaps with exit polls in the past, however.
In 1992, the exit poll indicated that a hung parliament was on the cards when Tory prime minister John Major had in fact won a slim majority.
Similarly, another hung parliament was considered the likely outcome by those behind the 2015 exit poll, with the Tories as the largest party.
Yet David Cameron ended up producing the first outright Tory majority in more than 20 years.
Fieldwork for 2019’s result will be conducted by opinion research specialists Ipsos Mori, with tens of thousands of interviews conducted at 144 polling stations across the country.
On leaving one of these stations, voters will be asked throughout polling day to indicate, using a mock ballot paper, how they had just voted.
Plymouth University’s Professor Colin Rallings, elections analyst for ITV News, said: “A volatile electorate, views on Brexit which cut across traditional party lines, and an election in the depths of winter all pose particular challenges for this year’s exit poll.
“But as ever, our experienced team will be working to ensure that another politician has to ‘eat their hat’ for doubting the story the poll foretells at ten o’clock on December 12.”
Sky News election guru Professor Michael Thrasher said: “In pubs and clubs, in homes around the country, people are watching and waiting for the ‘exit poll moment’, as the broadcasters time the declaration for the stroke of ten o’clock.
“Shock, disbelief, denial and disappointment for some. A pleasant surprise for others as the forecast exceeds expectations.”
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