Thursday 23 June 2016 7:45 am

The definitive guide to EU referendum night: From what time local areas will declare results, to the most marginal areas and key moments to look out for

Ballot slips are being distributed, campaigning is about to end, and today, after the seemingly endless stream of televised debates, grandstanding speeches, claims, counter-claims and fact-checking, voting actually take place.

Many across the country are preparing for a sleepless night. The polls opened at 7am and will close at 10pm, but the first results won't arrive until after midnight.

As it stands, there won't be an official exit poll – with pollsters saying it is just too difficult to conduct and might not be accurate enough. That hasn't stopped hedge funds reportedly commissioning their own private ones to get a head-start on the markets.

Read more: How to trade referendum night

With the official result not expected until after 6am tomorrow morning, and the most crucial results landing between 3am and 5am, here's our guide of what to look out for on the night, the results you don't want to miss, and how to tell who has the upper hand in the early contests.

Scroll down to find out how every single counting area is expected to vote.

Chris Hanretty, an academic at the University of East Anglia, has used British Election Study (BES) data – the most comprehensive opinion poll going – to chart the likely support for both Remain and Leave in nearly every one of the 382 areas that will be announcing results on Friday morning.

Stripping out the don't knows from the data (assuming they will vote in the same way the rest of their area does, which is by no means a certainty), we have a rough estimate of what proportion of votes the Remain and Leave side should be scooping up across the country.

Combining that with data from the Electoral Commission on expected times of declaration along with the size of electorates in each counting area provides us with a good snapshot of where we should be paying attention throughout the night.

The first results

The early results will come through at around 12.30am, here's how the BES suggests they should break, along with the relative importance – in terms of registered voters in that area – to help show who might be outperforming in the first results.

AreaDeclarationRegistered votersSize ranking

Expected vote (Remain – Leave)

Expected winner
Sunderland12.30am207,00039th40 – 60Leave by 20 points
Wandsworth12.30am220,00032nd69 – 31Remain by 38 points
City of London12.45am5,000379th77 – 23Remain by 54 points
Newcastle1.00am191,00053rd57-43Remain by 15 points
Oadby & Wigston1.00am43,000363rd47-53Leave by 6 points
Swindon1.00am149,00089th41-59Leave by 18 points

These first six – the only constituencies expected by 1am – make up just 1.8 per cent of the total electorate, so it will be hard to read too much into what they mean. Moreover, with none of the races expected to be particularly close, it should be pretty cut cut-and-dry here.

Turnout could be crucial, with polling wisdom suggesting higher turnout will help the Remain camp. If turnout is high and the gap between Remain and Leave stretches, it should bode well for the Inners. Conversely, if Leave manage to close in on Remain in Newcastle and Wandsworth – two relatively large areas – we could be on course for Brexit.

The most important results

With the size of counting areas varying dramatically, there are some results which are a lot more important than others. For instance, Birmingham accounts for 1.5 per cent of all voters and is expected to be one of the closest-run races of the night. Its results will be out at 4am and could be one of the biggest events of the whole evening.

Here are how the top five areas – making up 5.5 per cent of all votes – are expected to split, and when we'll know the results.

AreaDeclarationRegistered votersSize ranking

Expected vote (Remain – Leave)

Expected winner
Birmingham4.00am707,001st48 – 52Remain by four points
Leeds5.00am543,0002nd54 – 46Remain by eight points
Glasgow5.00am450,0003rd72 – 28Remain by 44 points
Cornwall6.00am420,0004th43 – 57Leave by 14 points
Sheffield4.30am393,0005th52 – 48Remain by 4 points

These five results are preceded by Durham, the sixth biggest area, at 3.30am, which is expected to be a 50-50 split between Remain and Leave. Therefore, the 3.30am-4.30am window where marginal powerhouses of Birmingham, Sheffield, Durham, Edinburgh, Wakefield and Croydon all declare results is where the action will be.

The most marginal results

Even though every vote counts and there are no "swing" seats as in a General Election, there are still some important bellwethers to look out for.

As we know, people are split by age, region, profession and party as to how they will vote. Nevertheless, there are some curious pockets across the country where areas are very finely divided.

AreaDeclarationRegistered votersSize ranking

Expected vote (Remain – Leave)

Expected winner
Lancaster3.00am100,554176th50.0 – 50.0Dead heat
Eden4.30am41,872364th50.0 – 50.0Dead heat
Broxtowe4.30am83,576242nd49.9 – 50.1Leave by 0.2 points
Craven4.00am44,320359th50.1 – 49.9Remain by 0.2 points
Stratford-on-Avon3.00am98,000187th49.8 – 50.2

Leave by 0.2 points

How the campaigns perform in these seats is vitally important to giving some clues about how successful they have been at shifting the don't knows and undecided voters to their side.

Both campaigns will be hoping the result is wrapped up by the time it gets to Chester East – the sixth most marginal, which Leave could take by 0.4 percentage points and holds 286,000 registered voters. It doesn't declare until 7am.

Remain strongholds

Both campaigns will also have their eyes on the results of their strongholds throughout the evening as a sign of how successful their "get-out-the-vote" operations have been.

The Remain side will get an early idea of this in some crucial constituencies, including metropolitan areas like Edinburgh, Cambridge, Lambeth and Camden – all expected to be at least 70 per cent for Remain and post results by 3.30am. 

AreaDeclarationRegistered votersSize ranking

Expected vote (Remain – Leave)

Expected winner
City of London12.45am6,000379th77 – 23Remain by 54 points
Edinburgh3.30am346,0568th76 – 24Remain by 52 points
Cambridge3.00am81,000257th75 – 35Remain by 50 points
Islington2.30am145,00093rd74 – 26Remain by 48 points
Oxford4.00am97,000188th73 – 27

Remain by 46 points

Leave fortresses

Brexit doesn't typically have resounding support in the largest urban areas, though a chunk of the larger areas (more than 100,000 registered voters) are where Brexiteers will keep eyes peeled to check those who want to leave the EU made the trip to the polling station.

Early results to look out for include Castle Point (2.30am), where Ukip came second in 2015, Basildon (2.00am) and Hartlepool (1.00am).

AreaDeclarationRegistered votersSize ranking

Expected vote

(Remain – Leave)

Expected winner
Fenland5.30am71,000290th27 – 73Leave by 46 points
Boston3.00am39,000366th28 – 72Leave by 44 points
South Holland5.00am66,000318th28 – 72Leave by 44 points
Castle Point2.30am69,000304th29 – 71Leave by 42 points
Great Yarmouth4.30am73,000285th30 – 70

Leave by 40 points

When will we know the result?

Not sure you've got it in you to stay up all night waiting? Or just want to be prepared for when the verdict will come down?

The official declaration of the final vote tally will be made around "breakfast time" from Manchester Town Hall. However, it's safe to assume we should have an idea of the outcome a few hours before then.

It'll likely be later than a General Election, however. With less than two per cent of results in by 1am, it's looking like it will be more like 3.30am-5am when the winner will emerge. The closer the vote, however, the later the result.

The chart shows what proportion of votes will have been announced, according to the half-hour time slot they are expected, along with the running total for the whole evening

Around 3am is where the action will really begin. The results in areas making up 19 per cent of the entire eligible electorate are expected around this time, with another 12 per cent estimated to arrive around 3.30am.

By 3.45am, we should have half of all the results. If either side has a decent lead – or has outperformed compared to how they are expected to go on the night.

As the chart below shows, after losing in the first few declarations, Remain will take the early lead once results start coming through in more significant numbers. Leave will want to peg it back, as their victories will chalk up later on in the early morning hours.

The Remain side's expected poll lead as a percentage of all potential votes cast.  After the first few results show the Leave side in front, Remain will take the lead.  After half the results have been counted, the Remain side will want to be up by around four points to be in with a shot of running home.

Here is where turnout is crucial. If votes go according to schedule, then Remain should edge into a lead in the first few hours of the night. The benchmark is a Remain lead of about four points by 3am. More than this and they'll be happy, anything less and Leave are ahead.

Every result

Of course, the result won't be won or lost just in these seats – they are simply useful bellwethers and matter a lot less than the 100-odd swing seats that decide the winner in a general election. 

Check here to see the expected result of every single counting area, along with the time they are estimated to make the announcement, and keep track of the two sides throughout the evening. 

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