The outlet reported Peters popped the question over the holidays in New York City, proposing with a "pink gold diamond ring."
People Magazine adds that, post-engagement, they headed to London to celebrate New Year's Eve.
The pair have been dating since 2012. They first met on the set of the independent film "Adult World" with John Cusack. (Via IFC Films)
The pair kept their romantic life pretty private, though, until last summer. (Via Instagram)
In July, Roberts was arrested in Montreal after a fight with Peters in their hotel room. There was apparently evidence she had bitten him, but Peters did not press charges. (Via TMZ)
The two released a statement saying it was all a misunderstanding, and they stayed together throughout the ordeal. And now, seems they'll be together forever, though neither has officially confirmed the engagement.