A New York jury has decided Donald Trump should pay $83.3m (£65m) for defaming columnist E Jean Carroll in 2019 while he was US president, reports BBC.
Mr Trump was previously found to have defamed Ms Carroll and to have sexually assaulted her in the 1990s.
The jury's penalty in the civil trial is made up of $18.3m for compensatory damages and $65m in punitive damages.
Mr Trump vowed to appeal, calling the case a witch hunt and the verdict "Absolutely ridiculous!"
The compensatory damages are meant to account for the harm his comments did to her reputation and emotional wellbeing.
The panel also had to come up with a punitive penalty intended to stop Mr Trump from continuing to speak out against her.
It took the jury of seven men and two women less than three hours to reach a verdict on Friday afternoon.
"This is a great victory for every woman who stands up when she's been knocked down, and a huge defeat for every bully who has tried to keep a woman down," Ms Carroll said in a statement.
Her attorney, Robbie Kaplan, said in a statement: "Today's verdict proves that the law applies to everyone in our country, even the rich, even the famous, even former presidents."
Earlier in the trial Judge Lewis Kaplan advised jurors not to use their real names with each other due to the sensitive nature of the case.
As it concluded, he advised them that they were free to discuss their experience. But he added that in his opinion they should not tell anyone they worked on this case.
Mr Trump has repeatedly denied any wrongdoing, or even that he has ever met Ms Carroll, including on Friday morning.
But following the verdict he refrained from attacking her directly when he slammed the outcome of the case in a post on his social media platform, Truth Social.
"I fully disagree with both verdicts," he wrote, "and will be appealing this whole Biden Directed Witch Hunt focused on me and the Republican Party.
"Our Legal System is out of control, and being used as a Political Weapon. They have taken away all First Amendment Rights. THIS IS NOT AMERICA!"
A civil trial last year found he sexually assaulted Ms Carroll, a magazine columnist, in a Bergdorf Goodman department store dressing room in the 1990s.
That jury also found him liable of defamation for calling her accusations a lie - and he was ordered to pay her about $5m in damages.
The case that ended on Friday focused on different defamatory comments by Mr Trump in 2019.
Mr Trump, who abruptly left court earlier in the day with his Secret Service security detail, was not present to hear the verdict.
His departure came moments after Judge Kaplan threatened to jail Mr Trump's lawyer, Alina Habba, for continuing to speak after he had told her to be quiet.
"You are on the verge of spending some time in the lockup. Now sit down," he told Ms Habba.
The judge had threatened to eject Mr Trump earlier after he muttered about the case being a "con job" and a "witch hunt" in court. Before the verdict was read, the judge warned: "We will have no outbursts."
During closing arguments earlier on Friday, a lawyer for Ms Carroll told the court her reputation had been severely harmed by the former president's comments denying he sexually assaulted her.
"This case is also about punishing Donald Trump... This trial is about getting him to stop once and for all," she said.
Ms Carroll's attorneys previously told the court that Mr Trump's statements unleashed a torrent of death threats, rape threats, and online vitriol towards her.
Mr Trump's lawyer had argued that he should pay no further damages to Ms Carroll as her claims have "more holes than Swiss cheese".
Ms Habba said that her client was not to blame for the threats that Ms Carroll received.
Mr Trump faces four criminal cases for a total of 91 felony counts, and is the first president in US history to be charged with a crime.
He has repeatedly claimed the various legal cases he faces are being orchestrated by allies of US President Joe Biden, a Democrat.
As the Republican party's White House frontrunner, Mr Trump looks set for a rematch against Mr Biden in the November 2024 general election.
Dmitriy Shakhnevich, a professor at John Jay College of Criminal Justice, told the BBC that Ms Carroll's lawyers had successfully argued only a significant amount of damages could compel Mr Trump to stop defaming her.
"What the jury is saying is this is a wealthy man who's not stopping, and the only way to stop him is to hurt him" financially, he said, calling the penalty "a very, very large sum".
University of Richmond law professor Carol Tobias told the BBC that "the lack of respect which Trump exhibited for the judge, the jurors, the opposing counsel, and especially Carroll" may have served to strengthen her case, and led them to determine that "a large damages award was appropriate and warranted".