Natasia Charlotte Demetriou is an English-Cypriot comedian, actress and screenwriter. She is best known for her roles as Nadja in the FX comedy horror series What We Do in the Shadows (2019–2024) and Sophie in the Channel 4 sitcom Stath Lets Flats (2018–2021).

In 2022, Demetriou co-wrote and starred in the BBC sketch show Ellie & Natasia, alongside her comedy partner Ellie White. The show was renewed for a second series in 2023. Natasia Charlotte Demetriou was born in London, the daughter of an English mother and Greek-Cypriot father. She was raised in North London. Her younger brother, Jamie Demetriou, is a comedian and actor with whom she often collaborates. She studied acting at the University of Leeds. Prior to becoming a professional comedian, Demetriou worked as a makeup artist, notably working on music videos for Boy Better Know.