O'Reilly had been scheduled to return from a vacation next Monday.
Of course, many claims of sexual harassment in the workplace are fabricated for whatever reason (though five cases is a lot).
Earlier this month authorities with the European Commission cleared 21st Century Fox to acquire the remaining 61% of Sky that it does not yet own. But "I'm not closing the door" on O'Reilly "just because there were allegations that were not confirmed", he said.
O'Reilly's departure is the second sex scandal to rock the network in less than a year.
It added that the network was committed to "fostering a work environment built on the values of trust and respect".
"The real subtext to all this is that Roger Ailes, the founding chairman, the creative drive behind the success of Fox, was forced out last summer for sexual harassment".
"But it is the unfortunate reality that man in the public eye must live with today", O'Reilly said.
O'Reilly was a ratings magnet at Fox - but it's hard to know how much of his audience would follow him to another network. "But the cost became too high when advertisers pulled out in droves and Fox's credibility took another major hit".
Fox News' Dana Perino sat in on Wednesday night.
Scott Baio clarifies blaming Erin Moran's death on drug use
The department says Moran died Saturday in the rural community of New Salisbury, about 20 miles northwest of Louisville, Kentucky. Moran followed that up with another post . "They've gone through their struggles and came out on top".
NY magazine reported Wednesday that executives were preparing to announce O'Reilly's departure before his return from Italy and were holding emergency meetings to discuss how to sever the relationship without damaging the network. Its leading female star, Megyn Kelly, also decamped for NBC in January.
Following the memo, Fox announced "Tucker Carlson Tonight" will begin airing an hour earlier to fill the time slot vacated byO'Reilly. On May 1, Eric Bolling, a co-host of "The Five", will debut an hourlong show in the 5 p.m. slot. On Tuesday, attorney Lisa Bloom said she was representing a former clerical worker at Fox who complained that day to a hotline established at Fox about O'Reilly's behavior during her six months working there in 2008.
Then, she said, she complained to Ailes, who resigned from the network a year ago amid allegations of sexual harassment.
The National Geographic channel says it has made no decision about its development of Bill O'Reilly's book "Killing Patton" following O'Reilly's exit from Fox News.
Some of O'Reilly's critics were happy with the news.
"I said, "Look, I am willing to give this another try, ' and he said, 'Sure" and I came on the show", Powers said.
Welcome to Fox News in the Donald Trump era.
Longtime Fox critics don't see it. Fox News has a "culture of harassment that did not start and does not end with Bill O'Reilly", said Rashad Robinson, executive director of the activist group Color of Change, which pressured advertisers to leave his show.
The risk for Fox News would have also intensified during the upfront advertising market, already in play, when companies decide where to make their advance commitments for commercial time that runs during the 2017-18 season. The controversy at Fox News led to speculation that it could threaten British approval of the company's proposed $22.9 billion purchase of British pay-TV provider Sky.