John Lithgow, Paapa Essiedu, Janet McTeer, and Nick Frost have been cast as Dumbledore, Severus Snape, Minerva McGonagall, and Rubeus Hagrid, respectively.

HBO has also announced new high-profile cast members: Rory Wilmot as Neville Longbottom, Amos Kitson as Dudley Dursley, Louise Brealey as Madam Hooch, and Anton Lesser as Garrick Ollivander.
It was previously announced that Lox Pratt will play Draco Malfoy, with Johnny Flynn as his father, Lucius Malfoy. Bel Powley and Daniel Rigby will portray Petunia and Vernon Dursley, and Katherine Parkinson will take on the role of Molly Weasley.
The series is written and executive produced by Francesca Gardiner, with Mark Mylod directing multiple episodes and serving as executive producer.