By RNZ reporter Nik Dirga

After one of the most unpredictable election years in American history, the country is finally nearly ready to choose its next president. Here's what you need to know about when to expect results.

Election Day is Tuesday, 5 November US time, and will decide whether Republican Donald Trump or Democrat Vice-President Kamala Harris will lead the country.

Trump would be the first former president to win a non-consecutive term since Grover Cleveland back in the 1890s, while Harris would be the first woman president.

When are results going to start rolling in?

For us watching in Aotearoa, voting will begin overnight New Zealand time on the evening of 5 November, and will close for the final state in the early evening Wednesday, 6 November.

Unlike New Zealand, Election Day is held during the work week, always on the first Tuesday after the first Monday in November. Federal law does not require people to get time off work to vote, although many states do allow people to take time off.

Here's the times polling begins to close in each of the 50 states. Some poll times may vary slightly due to local time zones. Daylight Savings Time begins 3 November in the US so time differences may not be accurate until after then.

6pm EST / 12pm NZ Time 6 November

Partial closures in Indiana, Kentucky

7pm EST / 1pm NZ Time

Florida, Georgia, New Hampshire, South Carolina, Vermont, Virginia

7.30pm EST / 1.30pm NZT

North Carolina, Ohio, West Virginia

8pm EST / 2pm NZT

Alabama, Connecticut, Delaware, District of Columbia (Washington DC), Kansas, Maine, Maryland, Massachusetts, Michigan, Mississippi, Missouri, New Jersey, North Dakota, Oklahoma, Pennsylvania, Rhode Island, South Dakota, Tennessee, Texas

8.30pm EST / 2.30pm NZT

Arkansas

9pm EST / 3pm NZT

Arizona, Colorado, Iowa, Louisiana, Minnesota, Nebraska, New Mexico, New York, Wisconsin, Wyoming

10pm EST / 4pm NZT

Montana, Nevada, Utah, Idaho

11pm EST / 5pm NZT

California, Oregon, Washington state

12 midnight EST / 6pm NZT

Hawaii, parts of Alaska

1am EST / 7pm NZT

The rest of Alaska

Some states will have the winners named almost instantly due to exit polling by organisations such as the Associated Press, while others may take some time to tally.

About 66 percent of eligible US voters, or 158 million people, turned up in 2020, the highest in decades.

What might hold the results up?

There are an unprecedented number of legal challenges already being thrown around in the race this year, such as in Georgia, where the courts have been arguing over a Republican-led challenge that would require poll workers to hand-count ballots, a change that voting rights groups warned could cause chaos.

Other last-minute court actions could end up delaying results in some states on Election Night. There are also concerns about possible violence at the polls due to the extremely heated rhetoric and conspiracy theories all floating around out there.

Aren't people voting already?

Yes. Since the Covid-19 pandemic, early voting has become much more popular in America and has seen a record turnout in many states this year.

Almost every state allows early voting, although some require an eligible reason to vote by mail.

Absentee ballots for US residents living overseas or military personnel went out a while back and sometimes take extra time to factor into the final results.

Image RNZ

What are the big states to look out for?

The seven swing states that may decide this year's election due to the vagaries of the Electoral College are considered to be Arizona, Nevada, Pennsylvania, North Carolina, Wisconsin, Georgia and Michigan. All but two of them - Arizona and Nevada - are on the eastern side of the US, which means we may know most of their results earlier.

Read more:

• What you need to know: The Electoral College explained

An awful lot of the most populated states are pretty much guaranteed to go solidly for one candidate or another - California and New York are certain for Harris, while Texas and Florida are quite likely for Trump. It's the ones on the tipping point that will decide the election.

So when do we usually know a winner?

It's not uncommon for the presidential winner not to be named on Election Night. Joe Biden's victory in the 2020 election wasn't officially declared until 7 November - four days after the 3 November vote.

Sometimes a winner becomes clear earlier, as when Republican John McCain conceded in 2008 on Election Day shortly before 11pm in the eastern US, before polls in the last few states had closed. On the other hand in 2000, the tight battle between Democrat Al Gore and Republican George W. Bush was only settled by the US Supreme Court on 12 December.

If there is a landslide towards one candidate or another - say, if Trump or Harris sweep east coast states like Pennsylvania, North Carolina and Georgia - it's possible the picture may become clear by late afternoon NZT on 6 November.

But at this point, anyone who says they know for certain exactly what time America's next president will be decided is taking a shot in the dark.

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