On election night 2020, then-President Donald Trump prematurely declared hours after polls had closed: “We already have won.”

He hadn’t, and we rated that “Pants on Fire”. When Trump began to speak in the early morning of November 4, at 2:21am ET, states were still following normal procedures to count ballots. It was not until Saturday, November 7, that The Associated Press had sufficient unofficial results available to call the race for Joe Biden.

In the past, when polls closed, politicians and social media influencers spread falsehoods about voting and the ballot-counting process. It’s likely that as the votes are being counted this year, we will see falsehoods similar to those in 2020.

Voters who are seeking credible sources for election results information can follow reports from state election officials nationwide, compiled by the National Association of State Election Directors. The AP is among the news outlets that will call projected winners based on unofficial results, but in many states that will not take place on election night.

Here are some falsehoods that might surface after the polls close.

Claims about thousands of dead voters

It’s a zombie claim we see during every election cycle: huge numbers of dead people are voting! And they are all Democrats! Neither is true.

As ballot counting was under way in November 2020, X posts falsely said that more than 14,000 dead people voted in Wayne County, Michigan.

Typically when voters die, it’s rare that their relatives contact local elections offices to ask that their names be removed from voter rolls. But election offices routinely receive death records from state and federal sources and then remove dead voters’ names from voter rolls. Some still end up on the rolls.

Occasionally, people illegally cast mail ballots in dead relatives’ names, as a Republican did in 2020 in Nevada. That voter was charged with felonies.

Claims that ballot errors and election site mishaps equal fraud

Although election officials spend years preparing for presidential elections, errors sometimes occur.

They are not a sign of fraud.

So far this year, we have seen a limited number of ballots with errors, such as a typo in some ballots in Palm Beach County, Florida. County officials said 257 overseas voters opened an email with a ballot that said “Tom” Walz instead of Tim Walz, Democratic presidential nominee Vice President Kamala Harris’s running mate.

Some election sites have mishaps, such as a 6am water leak on Election Day in 2020 at Atlanta’s State Farm Arena, where election workers were counting absentee ballots. Arena staff repaired the leak in about two hours and no ballots or machines were damaged. State and county election officials debunked the claim that election officials used the event to circumvent processes and pull out ballots stored in “suitcases” that were “all for Biden”.

Claims of thousands of fake votes in Pennsylvania

Lancaster County, Pennsylvania, officials said in an initial October 25 statement that they were investigating 2,500 “ballots”, but a county spokesperson later said that word was a mistake and the investigation was into voter registration applications.

Days later, Trump falsely said at an Allentown, Pennsylvania, rally: “We caught them with 2,600 votes. … And every vote was written by the same person.” He made similar comments on X about “fake ballots and forms” in Pennsylvania.

Pennsylvania Attorney General Michelle Henry, a Democrat, said in an October 31 statement: “The investigations regard voter registration forms, not ballots” and were under way in four counties.

Officials do not place people on voter rolls if their registration is suspect, so that means that there were not thousands of fake votes.

Claims about machines flipping votes

As Kentucky’s Republican Secretary of State Michael Adams wrote on November 2 on X: “Gentle reminder that vote-switching is fiction.” He linked to a 2008 video of Homer Simpson trying to vote for Barack Obama but repeatedly voting for former Senator John McCain, R-Ariz.

Election officials facing reports of “flipped” or “switched” votes have said that sometimes that is user error and, when voters bring it to their attention, officials make sure voters can cast ballots with their desired choices.

That is what happened in Tarrant County, Texas, when one person out of more than 100,000 voters reported having a vote for Trump changed to Harris when the ballot was printed. Local election officials said the voting machines were not flipping candidates and suggested the voter made a mistake when selecting preferred candidates. That ballot was destroyed and the voter was allowed to vote again.

An October Instagram post said voting machines in Shelby County, Tennessee, were swapping votes from Harris to Trump. Election officials said there were no voting machine malfunctions. Voters had inadvertently touched the wrong area of the ballot when using the touchscreen voting machines.

Rampant non-citizen voting does not occur

Trump and his supporters have falsely claimed that Democrats are behind a scheme to lure non-citizens to the US to vote in federal elections. That’s not happening.

Federal law bans non-citizens from voting in federal elections.

Non-citizens sometimes land on voter rolls, often by accident when getting driver’s licences. However, voting by non-citizens in federal elections is rare. The largest case with convictions we found was in 2020 in North Carolina, when federal prosecutors charged 19 people with voter fraud after they cast ballots, mostly in the 2016 election. For context, more than 4.5 million people in North Carolina voted in the 2016 presidential election.

Claims that election officials rip up or trash ballots

If you’re an election worker committing election fraud, you probably wouldn’t film yourself opening mail ballot envelopes, calling out the votes in those ballots, cursing against one candidate and ripping up ballots marked for that candidate.

But that’s what one ridiculous viral video appears to show, leading X users to claim that mail ballots with votes for Trump are being destroyed in Bucks County, Pennsylvania. Federal officials said Russian actors manufactured and amplified the video.

Claims in 2020 about large numbers of ballots found in the rubbish were either made up or were about spoiled ballots that were legally destroyed.

Claims that election officials sneak in ‘ballot dumps’ late at night

It is common for one candidate to take the lead in early results but not be the winner as more ballots are counted. For example, in Pennsylvania, if it takes longer to count votes in left-leaning Philadelphia than in a more right-leaning part of the state, it’s possible that Trump could lead the state early in the night but see the margins shift later.

Trump tweeted the claim on November 4 2020: “Last night I was leading, often solidly, in many key states, in almost all instances Democrat run and controlled. Then, one by one, they started to magically disappear as surprise ballot dumps were counted.”

In some states, Trump did initially lead, only to see Biden eventually take the lead. But in other states, Biden led and Trump came back to take the lead.

There is nothing nefarious about local election officials updating results in the hours and days after polls close. In fact, it means they are counting all legitimate ballots. State laws dictate the process, including when officials can start opening mail ballots. That means it takes time to finish the count. Some states, such as Pennsylvania, do not allow election workers to begin processing mail ballots until Election Day, while other states allow that to begin weeks earlier.

Claims that mass voter fraud in 2020 affected the election’s outcome

After the polls closed in 2020, a cascade of social media images and photos claimed to show poll workers and others committing voter fraud. But the posts mostly showed election officials doing their jobs.

The election system in our country makes such a heist both unlikely and impossibly elaborate.

“We should call this what it is: Trump laying the groundwork so he can cast doubt on the 2024 results if he does not win,” Joanna Lydgate, CEO of the nonpartisan States United Democracy Center, told PolitiFact in early October.

To build a sufficient Electoral College margin, bad actors would have to collaborate across battleground states in a coordinated but secret way, with hundreds of people risking felonies for the same goal.

Pulling this off would require thousands of illegal votes. A database maintained by the conservative Heritage Foundation shows about 1,300 convictions for voter fraud over decades. During that period, billions of votes were cast.

Claims of early victory

Speaking at the White House hours after the polls closed in 2020, Trump said: “We want all voting to stop. We do not want them to find any ballots at 4 o’clock in the morning and add them to the list, OK? It’s a very sad moment. … And we will win this.”

There is no state or federal law that says vote counting must stop a few hours after the polls close. Election officials would have violated laws if they simply stopped counting legitimate ballots.

State laws set the certification deadline in November or December, so the official results will not be known for weeks after Election Day. However, media outlets are likely to project a winner far earlier than that.