Planning on pulling an all-nighter? Here's every question you'll have during coverage, answered.
What time do the polls close?
Polls close at 10pm, very shortly after which the first exit poll, conducted by the BBC, will come out. In the past, they've been pretty accurate - predicted the outcomes of the 2005 and 2010 General Elections. This time, though, seven-party politics mean forecasting is more complicated.
Why is no one reporting polls until 10.00pm?
Guidelines from Ofcom say to avoid influencing voters, broadcasters must not report any polls until voting finishes at 10pm
Which is the first constituency to declare?
The counters of Houghton and Sunderland are famously speedy - they're expected to declare at 11.08pm, according to SportingIndex. At 1.00pm on Friday, St Ives in Cornwall will finally declare its figures - although by that time, the nation is likely to have decided (or not).
How do I know who's standing in my constituency?
Interesting you asked. Find out everything you need to know about your constituency here.
When will we know who's won?
By 6.00am or 7.00am, the majority of constituencies will have declared and we'll have an idea of who's in the majority - albeit a narrow majority. In the very likely event there's a hung parliament, negotiations could go on for days - although it has been suggested that if the country is left hanging for more than two weeks, another election is likely to be called.
How many seats are needed to win the election?
A party needs to win 326 seats to win a majority. It's unlikely that will happen tonight.
Where can I watch it?
If you're abroad, BBC World and CNN International are both broadcasting versions.
How long do I need to stay up?
It's going to be a long night.
There's been a lot of talk about key marginals, but the most interesting seats are the ones where big names are fighting for their jobs. East Renfrewshire is one such constituency - Scottish Labour leader Jim Murphy goes head-to-head with SNP rival Kirsten Oswald at 3.00am, while Lib Dem leader Nick Clegg finds out whether he's been dethroned in Sheffield Hallam at 4.30am, and Nigel Farage will discover whether South Thanet wants him at 5.00am.
Get the coffee in: you'll need it.