Brexit referendum: What happens once voting stops?

Thursday night will see one of the most important stock market and political questions of the year - whether the U.K. will remain part of the European Union - finally answered. How will the results unfold?

Polls will close around the U.K. in the referendum. While there won't be traditional exit polls from U.K. national broadcasters in the manner of a general election, the results of some alternative exit polls, including one by YouGov, may be available.

Early results from around the country are expected to start arriving .While it is only the overall share of the vote gained by either Leave or Remain which really matters, these results should give a flavor of which way the country is turning.

There are 382 counting areas in total, varying in size from 1,700 to 700,000 eligible voters. Sunderland, in the North of England, Wandsworth in London and Foyle in Northern Ireland are expected to be the first to report. Watch out Sunderland, with its Labour-voting, blue collar demographic,as it is expected to be a key indicator of whether the Leave campaign has swayed this demographic, according to Open Europe, the think tank.

A flurry of results are expected during this period, and areas representing around 75 percent of the U.K. population should have declared by now.

Key areas to watch for include Conservative Party strongholds like Cheltenham, according to Open Europe.

The final results are expected to come in, with a declaration of the result made in Manchester. If U.K. voters have opted for Leave, the political fallout of the campaign, particularly the divisions exposed in the ruling Conservative Party, is expected to escalate quickly.

London's stock markets are due to open. In the event of a Leave vote, trading may be suspended, according to a warning from U.K. Chancellor of the Exchequer George Osborne. If the Leave campaign has triumphed, this is likely to be one of the year's busiest trading days as market participants digest the result.