Sonia, Sonja or Sonya, a name of Greek origin meaning wisdom, may refer to:
People
- Sonia (name), a feminine given name (lists people named, Sonia, Sonja and Sonya)
- Sonia (actress), Indian film actress in Malayalam and Tamil films
- Sonia (singer), British pop star Sonia Evans
- Sonia, code-name of Ursula Kuczynski, also known as Beurton, a spy for the USSR
- Queen Sonja of Norway
- Sonia Ben Ammar, French fashion model, actress and singer known mononymously as SONIA
- Sonia people, an ethnic group on the Great Papuan Plateau of Papua New Guinea
Other
- Sonia, the allied code name for the Mitsubishi Ki-51, Japanese WW2 era bomber
- SONIA, Sterling OverNight Index Average, a financial market rate
- Sonia (album), a 1991 album by Sonia Evans
- Sonia (film), a 1921 British silent film
- Sonia (genus), a genus of moths
- M/V Sonia, a passenger ferry