Bill Istvan Günther Skarsgård was born in Stockholm on August 9, 1990. The son of renowned actor Stellan Skarsgård grew up with five siblings, and his elder brothers Alexander, Gustaf and Valter also pursued acting careers. At age nine, Bill made his screen debut alongside his brother Alexander in the Swedish thriller "Järngänget" ("Reißende Wasser", 2000). Since then, he has appeared in several Swedish film and TV productions, for instance with his father and brother Gustaf in the period drama "Arn – Riket vid vägens slut" ("Arn: The Kingdom at Road's End", 2008).
For his portrayal of an autistic person in the tragicomedy "I rymden finns inga känslor" ("Im Weltraum gibt es keine Gefühle", 2010), he received a nomination for the Swedish Film Award. In 2011, he starred in the titular role of the Swedish-German co-production "Simon", which is set in Sweden during the Second World War. The next year, he was named one of the "European Shooting Stars" at the Berlin IFF.