Polling stations have opened as voters decide whether Britain should stay in or leave the European Union.
Polls opened at 7am and will close at 10pm. In total, 46,499,537 people are registered to vote in the referendum — the biggest electorate in the history of British elections.
The final polls going into today’s historic vote have given the Remain camp a small lead, but the race remains too close to call.
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A YouGov survey put the In campaign slightly ahead on 51-49, still within the usual three-point margin of error for opinion polls.
Rival group Opinium gave Leave a 45-44 lead, with 11% of voters still to make up their minds, while a ComRes poll for the Daily Mail gave Remain a six-point lead, with a similar number of undecided voters.
In its latest pre-poll commentary, YouGov said the race was still impossible to predict, but the company noted there had been a late trend towards a Remain vote.
At the same time, they said they expected a number of voters to only make their mind up today.
With the race so finely balanced, some commentators have suggested factors such as the weather today could play a crucial role, with inclement conditions likely to mean a lower turnout.
Politicians on both sides of the argument spent yesterday making their final pitches to voters.
David Cameron and former prime ministers Tony Blair, Gordon Brown and Sir John Major issued a joint plea last night for Britons to cast their vote for Remain.
Cameron drilled home his message that there was “no going back” in the case of a Leave vote, and said Remain had the “biggest coalition of support in history — from businesses, to trade unions to expert economists and across political parties - for a vote to remain”.
Leading Brexit campaigner Michael Gove, meanwhile, told the Daily Mail this was “D-Day… democracy day”.
The justice secretary compared the UK leaving the EU to the US fighting for independence from the British Empire.
“The decision the American Revolutionaries had to make in the 1770s about whether or not to continue to be ruled by someone who was distant and unaccountable, who imposed taxes without listening to their voices or whether to break free.
“They decided to break free then and America has never looked back and the world had cause to be grateful.”