The FBI director said a fresh inquiry into the democratic candidate’s communications found nothing to change the Bureau’s conclusion this summer.
Mr. Trump said Hillary Clinton is guilty. She knows it and he said the FBI knows it.
The Clinton campaign said it was “glad” the lingering issue had been resolved.
The dramatic twist lifted a cloud from her campaign as the final day of the marathon US election race loomed.
The latest opinion polls on Sunday, before news broke of the FBI announcement, gave Mrs. Clinton a four- to five-point lead over Mr. Trump.
Mrs. Clinton used a private email server when she was Secretary of State from 2008 to 2012 in the Obama administration.