Citing a source, the magazine said the couple and "Twilight" actors broke up after Pattinson bailed on his 27th birthday plans, which Stewart had arranged.
The source said it was still possible the couple might reunite.
They separated for two months, during which Stewart penned an open-letter apology to Pattinson and professed her love for the actor publicly for the first time.
Since then, the couple had been spotted holding hands at the Coachella festival, and spending time together after the Met Gala, the annual ball celebrating the Metropolitan Museum of Art's annual fashion exhibit, May 8 in New York, People said Saturday.
