The rep added that Sony supports the decision, which was made by the film's director, Ridley Scott.
News of the replacement comes on the heels of the film being pulled from the American Film Institute (AFI) film festival, after multiple sexual misconduct allegations have emerged against Spacey.
The upcoming thriller, co-starring Michelle Williams and Mark Wahlberg, was set to be released on Dec. 22. Despite replacing one of the lead actors, Scott is intending to keep the film's release date next month, according to The Associated Press.
TriStar Pictures, a division of Sony, said previously that the film was being withdrawn from the AFI festival "out of respect for those impacted" by the actor.
"'All the Money in the World' is a superb film and more than worthy of its place of honor in the AFI Fest. But given the current allegations surrounding one of its actors and out of respect for those impacted, it would be inappropriate to celebrate at a gala at this difficult time," Tristar Pictures said in a statement.
Spacey, 58, was accused Wednesday by Heather Unruh, a former TV news anchor, of sexually assaulting her son when he was 18. A rep for Spacey did not respond immediately to ABC News' request for comment on Wednesday.
The actor has also been accused of making an unwanted sexual advance toward actor Anthony Rapp in the 1980s when he was just 14 years old, and groping Richard Dreyfuss' son, Harry, among other allegations. His publicist has not responded to ABC News' requests for comment, though People magazine reported last week that a representative for the actor said that Spacey "is taking the time necessary to seek evaluation and treatment."
Spacey issued an apology in the wake of Rapp's accusations, saying, "I honestly do not remember the encounter, it would have been over 30 years ago. But if I did behave then as he describes, I owe him the sincerest apology for what would have been deeply inappropriate drunken behavior."
After the allegations surfaced, Netflix and Media Rights Capital, the companies behind Spacey's show, "House of Cards," announced that production on the series had been suspended. Last week, Netflix also stated that it had severed ties with the actor.
ABC News' Michael Del Moro, Lesley Messer and Luchina Fisher contributed to this report