Election 2024: what happens on the big day – and at what time

After an eventful election campaign, voters across the UK are making their final decision. Polls have indicated for some time that the Conservatives, led by Rishi Sunak, are on course to lose to Labour and that Keir Starmer will become the first Labour prime minister in 14 years.

Many electors have already exercised their democratic duty by voting by post. At the last election, 21% of votes in Great Britain were cast this way.

The percentage of people voting by post has soared in recent decades, now that anyone who wants one can get one – rather than having to give a specific reasons to qualify for one.

Read more: Election 2024: how many seats every party in Westminster is defending – and what they are aiming for on July 4

The last time a reason was still required was the 1997 election – and back then, only 2% cast their vote by post. A reason is still needed in Northern Ireland – and in 2019 only 2% of the electorate voted by post. Even there though, applications for postal votes have doubled (to 25,000) for this contest. School terms have already ended in Northern Ireland and Scotland, so many voters may be on holiday and will have wanted a postal vote.

10pm: the exit poll lands

Whether with excitement or trepidation, everyone is anticipating the broadcasters’ 10pm exit poll. Previous erroneous exit poll forecasts, of a slim Conservative majority of 26 in 1987 (actual 102) and hung parliament of 1992 (Conservative majority 21) are distant memories. The exit poll is now very accurate.

Indeed, the last time Labour won an election, in 2005, the exit poll predicted an overall majority of 66, absolutely spot on. In 2019, the exit poll put the Conservatives on 368 seats and they ended up with 365.

The Broadcasters’ Exit Poll (GB-wide parties) since 2010

Given this accuracy, it is little wonder that broadcasters devote much of the opening hour (and beyond) of their election night programmes to analysis of the exit poll and its potential implications.

10pm-midnight: early declarations

That focus on the exit poll also reflects the dearth of constituency results before midnight. Only three constituencies were declared in the first two hours after the polls closed in 2019 – and these early calls are now a competitive sport between election officials.

Newcastle-upon-Tyne Central’s 11.27pm verdict pipped Houghton and Sunderland South by two minutes in 2019. One of Sunderland’s constituencies was the first to declare at all six elections from 1992 to 2015, with Newcastle pipping its local rival at the two contests since.

Indeed, the first hours of election night coverage owe much to north-east England as well as the exit poll. The first first six declarations in 2019 all came from the region. Hard work, rapid transport, lots of counters and the use of small vote bundles – so no-one loses count – explain the region’s counting prowess.

Midnight-4.30am: the big results

The story of the 2019 election was effectively told just before midnight, when Blyth Valley (now absorbed into the new constituency of Cramlington and Killingworth) became a Conservative seat for the first time ever.

The second Conservative victory in 2019 was Swindon North, 30 minutes into Friday morning. The same seat will offer an important early indication of whether the predicted Labour landslide is reality.

Labour needs to overturn a majority of just over 16,000 to take Swindon North, which would be a sure sign of a Labour government with an overall majority. If Labour wins big here, the Conservative meltdown forecast by many polls looks likely.

Read more: Election 2024: these are the races to watch

Success in Scotland would enhance a Labour landslide. The first Scottish declaration in 2019 was an SNP gain from Labour, in Rutherglen and Hamilton West (now Rutherglen following boundary changes). Labour recaptured the seat in a byelection last year and will look for a substantial majority to confirm it will become Scotland’s largest party for the first time since 2010.

The period from 2am until 4.30am is results peak, with an average of three declarations per minute. Landslide-watchers should look out early in those hours for seats such as Southport, and later Macclesfield, turning red for the first time.

Former Labour party leader and now independent candidate Jeremy Corbyn’s result in Islington North should offer an interesting sideshow soon after 3am.

Chancellor Jeremy Hunt, in his new constituency of Godalming and Ash, along with education secretary Gillian Keegan in Chichester, will hear around 4am whether they have succumbed to a Liberal Democrat insurgency.

Although the game might be long up, unless the polls are spectacularly wrong, Rishi Sunak may hold off any concession speech until his own count.

The last time the Conservatives were losing power, John Major conceded the election publicly at his Huntingdon constituency declaration, even though he had phoned congratulations privately to Tony Blair an hour earlier.

We might be waiting a while. Sunak’s Richmond (now Richmond and Northallerton) seat did not declare until 4.14am in 2019. That might be good timing, though. Keir Starmer’s Holborn and St Pancras result followed six minutes later at the last election.

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Last to declare in 2019 was St Ives. With ballot boxes transferred from the Isles of Scilly, its result, at nearly 3pm on a Friday afternoon, came nearly seven hours after the penultimate declaration.

By then, events will have moved apace. Assuming an overall majority government, the King will have seen the new prime minister and a cabinet will be formed within 48 hours. New MPs will be sworn into parliament next week and the King’s speech, outlining the new government’s programme will be read to parliament on July 17.

Jonathan Tonge does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.