According to a CNN report citing two sources, the payout is the result of O'Reilly's newly signed contract with FNC parent company 21st Century Fox in late March.
One source described the amount as "staggering," though neither sources would specify an amount. CNN put it at "tens of millions."
The sources told CNN that O'Reilly was to be paid $25 million a year under the contract, which covered him through 2020 0r 2021, which would include the next presidential election. Previous reports had it between $18 million to $20 million.
But O'Reilly won't be getting the full amount of his remaining contract. The company may have learned something from its recent ousting of former Fox News CEO Roger Ailes after he was accused of sexual harassment in July by multiple women. In that case, Ailes was paid the remainder of his contract, a sum reportedly more than $40 million.
According to CNN's sources, Fox placed some exit clauses in O'Reilly's contract in case his employment ended before it expired.
21st Century Fox didn't immediately respond to Business Insider's request for comment. CNN reports that both O'Reilly and Fox are banned from speaking about the payout by confidentiality agreements.
O'Reilly's exit comes after an explosive report by The New York Times, which found that Fox and O'Reilly had paid $13 million in settlements to women who accused the host of unwanted sexual advances, new sexual-harassment accusations, and an exodus of more than 20 advertisers from "The O'Reilly Factor."
The host left the top-rated show on cable news after the Times report, claiming that he was taking a previously planned vacation. But on Wednesday, Fox issued a statement confirming that he "will not be returning to the Fox News Channel."