Amanda Seyfried has confirmed that Mamma Mia! 3 is officially in development. During a recent interview at the Toronto International Film Festival, she told Deadline, “It is, yes… I think,” adding that the cast is on board and that big movies like this are all about studio timing. Producer Judy Craymer has also confirmed that a script is complete and that the project is in its earliest stages. While no filming has begun, the film is expected to reunite the original cast, including Meryl Streep, Christine Baranski, and Pierce Brosnan, and may introduce new characters, potentially played by Sabrina Carpenter. The film is anticipated to be set in Greece, with filming ideally commencing in summer 2026.