It's decision time for millions of people in the UK, including over 330 thousand Irish people.
Polling stations in the British EU Referendum have opened with a high turnout expected.
If Britain does decide to LEAVE the EU it could take at least two years.
A result is likely tomorrow morning.
There are around 330 thousand Irish people living in the UK that are eligible to vote.
Most opinion polls put the “Leave” and “Remain” camps neck-and-neck at the end of a campaign that was dominated by immigration and the economy and shaken by the murder of a pro-EU MP, though late polls last night two showed a swing to “Remain”.
The “Leave” campaign says Britain's economy would benefit from a Brexit, or British exit. Mr Cameron says it would cause financial chaos.
Traders, investors and companies are preparing for volatility on financial markets whatever the outcome of a vote that both reflects, and has fuelled, an anti-establishment mood also seen in the United States and elsewhere in Europe.
