The full 2015 general election result will not be be known until 2.30pm on the day after polling day.
Polls close at 10pm on Thursday 7 May – but the result will take a while to come through.
Data released by the Electoral Commission on Tuesday shows that at least seven constituencies, including three key marginal seats, don't expect to declare their results until late on the morning of Friday 8 May – by which point most politicians, journalists, and viewers will be tired, grumpy, and losing the will to continue.
With polls predicting a hung parliament, the exact balance of power could depend on results in seats that are only expected to finish counting at least 12 hours after polls close.
Most of the UK's 650 constituencies will have declared by 4am, but returning offices in the Northumberland seats of Berwick-upon-Tweed, Blyth Valley, Hexham, and Wansbeck say they only expect to declare their results at 9.30am on Friday 8 May.
The two Warwickshire seats of Kenilworth and Southam, plus Warwick and Leamington, are expected to have their results by 10am.
St Ives in west Cornwall is expected to be the final result of the 2015 general election at around 2.30pm.
Although delayed results in a handful of seats would not normally be noteworthy, three of these constituencies are marginal seats and could be crucial in the event of a hung parliament.
Instead, the political audience will have to pull an all-nighter while watching the likes of BBC presenter David Dimbleby, who BuzzFeed News understands makes it through election nights on a diet of honey and bananas – but no coffee.
Jim Waterson is a politics editor for BuzzFeed News and is based in London.
Contact Jim Waterson at firstname.lastname@example.org.
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