According to E!, the pair, who first met as love interests for their respective characters on Entourage, have decided to end their two-year relationship.
The news comes just two months after they were househunting together in Los Angeles.
Sigler was recently spotted walking in New York City with former 'N Sync member Lance Bass. Ferrara has been seen partying in LA with co-star Kevin Connolly.
Sigler's rep did not comment. However, a spokesperson for Ferrara said: "I don't know anything about that. It's news to me if it's true."