The race for the White House is coming down to who wins the few remaining battleground states – Georgia, Pennsylvania, Nevada and Arizona.
A win in just Pennsylvania or two of the other four remaining states would be enough to confirm Mr Biden as president-elect, barring any legal challenge.
Mr Trump, meanwhile, needs to win Pennsylvania and three of the remaining four states.
Here’s the state of play in the states at play.
GEORGIA – 16 electoral votes
Where things stand: The BBC’s results system is showing a Biden lead in Georgia of just over 1,500.
How many votes are still to be counted: Georgia Secretary of State Brad Raffensberger said on Friday that 4,169 votes remain to be counted, and that some 8,000 military absentee ballots are still in the mail and will only be counted if they arrive by the end of the day.
Where are these votes? The votes being counted are postal ballots mostly from Atlanta and Savannah, which have skewed heavily toward Biden.
When will we learn more? Raffensberger announced on Friday that the state’s presidential contest will go to a recount, so we could be waiting a while.
PENNSYLVANIA – 20 electoral votes
Where things stand: Biden is now leading Trump by 9,027 votes, according to the BBC’s election system.
How many votes are still be counted: Just over 163,000 votes remain.
Where are these votes? In counties won by Hillary Clinton in 2016, so mostly Democratic votes.
When will we learn more? State officials said they hoped to count the “overwhelming majority” of the outstanding votes by the end of Thursday. That raises the possibility of a projection on Friday morning. Let’s see.
ARIZONA – 11 electoral votes
Where things stand: Biden still has a lead of about 43,000 – but Trump has been gaining steadily throughout the day.
How many votes are still be counted: As of Thursday night, there were approximately 300,000 ballots outstanding.
Where are these votes? They’re from all over this diverse state, but most are in the area around Phoenix.
When will we learn more? We’re expecting another batch of results at 09:00 local time on Friday (16:00GMT) – we don’t know how many or if they’ll prove decisive.
NEVADA – 6 electoral votes
Where things stand: Biden is holding his lead over Trump by around 20,000 votes, according to the latest results.
How many votes are still to be counted: Officials say there are about 190,000 ballots remaining.
Where are these votes? About 90% of the votes are from Clark County which includes Las Vegas, and the majority of them are postal ballots.
When will we know more? An additional 51,000 ballots will be reported on Friday, according to Joe Gloria, an official in Clark County. A clearer result will likely come by the weekend.
BBC