The polling stations have closed in Britains big decision on whether to leave or remain in the European Union. Heres what you need to know about the count now taking place. Conversation editors are updating this article through the night of June 23 and morning of June 24.

When might we expect a result?

If the vote is as close as opinion polls suggest, well be unlikely to get an official result before 8am UK time on Friday. Counting is taking place overnight. The first results were from 11pm onwards but around half will not be declared until after 4am. If counting proceeds efficiently and one side has built up a clear lead, it may be possible to project the outcome accurately by around 5am.

Will there be an exit poll?

There is no official exit poll. Polling companies have conducted referendum day polling but these are not exit polls. It is understood exit polls have been commissioned by hedge funds looking to make financial gains in international currency markets. These exit polls will not be published and their likely reliability has been questioned. Attempts to infer the results from movements in foreign exchange trading may be misleading.

Exit polls at general elections are based on measuring changes in support for parties from the previous election in a large number of carefully chosen polling districts. It is impossible to replicate this approach for a one-off electoral event such as a referendum.

Is counting the same as in a UK general election?

There are a few differences to how counts take place at a British general election. Counting is happening in 382 counting area (380 local authorities in England, Wales and Scotland, plus Northern Ireland as a whole, and also Gibraltar) rather than in 650 parliamentary constituencies.

Unlike a general election, what matters is not so much who wins in each counting area but how many votes are secured by the rival campaigns along the way. The totals for Leave and Remain will be aggregated at a regional level and declarations made by regional counting officers. Once all the regional counts are complete, the UK result will be announced from Manchester by Jenny Watson, chair of the Electoral Commission.

Will results be announced along the way?

Yes, each of the 382 counting areas are announcing their results. These local results will be relayed by the broadcasters but it will be difficult to keep up once they start to come in thick and fast at around 3am. It should also be possible to track local results via council websites and Twitter feeds. There will also be rumours and speculation about local outcomes circulating on social media. They should be treated with a degree of caution in advance of official declarations.

Could any areas give an indication of the result?

Early results will require careful interpretation. Metropolitan areas outside London with very large electorates, notably Birmingham and Leeds but also Sheffield, Liverpool and Manchester, could prove crucial and are expected to declare from 4am to 5am.

For Remain, low margins of victory or low turnouts in these cities could spell very bad news. If the totals remain close at 6am, when Cornwall (circa 400,000 electors) is due to declare, a clear lead for either side on a relatively high turnout may suggest which way the wind is blowing.

Key results to look out for?

Unlike a general election, there are no safe and marginal seats. However, the socio-demographic make-up of each counting area and past support for UKIP are expected to provide a strong indication of how individual areas will vote. On this basis, early results from Scotland and London could be seen as safe for Remain. Conversely, parts of the east coast such as Great Yarmouth, North Norfolk, Boston and South Holland should be safe territory for Leave.

Some counting areas come close to representing the socio-demographics of the country in microcosm. Swindon, often regarded as a barometer town in politics, is expected to declare at around 1am. A clear lead for either side here could be indicative of a wider pattern.

What amounts to a decisive victory?

Given how tight the polls have been, a ten-point margin of victory (for example, 55% to 45%) will almost certainly be interpreted as decisive. However, for the issue to be considered settled, at least in the short term, a margin of victory for Remain over Leave would have to be at least 60% to 40%. A narrow victory for Leave, for example 51% to 49%, could be one of the most problematic outcomes from a political perspective, particularly if secured on the back of a relatively low turnout.

What amounts to a close result?

Anything within the margins of 47:53 either way will probably be seen as close and the polls suggest that such an outcome is clearly possible. Ultimately, the vote can be won by a margin of just one vote. That is the nature of a referendum.

Recounts can be requested in individual counting areas but only prior to official declarations being made. There is no legal provision for a national recount. The only means of challenging the result will be via judicial review.

Should I stay up for the result or go to bed?

Staying up until breakfast time for the official result is possibly going to be the preserve of the political obsessive. Assuming the opinion polls are broadly correct (admittedly a big assumption after the last general election) and the vote is as close as expected, the real excitement is likely to be from 5am onwards, at which point it may be possible for broadcasters to project a winner.

Author: Stuart Wilks-Heeg | The Conversation