Hostiaz was commune in the Auvergne-Rhône-Alpes region in the Ain department in east France. On 1 January 2019, it became part of a new commune called Plateau d'Hauteville.
Hostiaz was commune in the Auvergne-Rhône-Alpes region in the Ain department in east France. On 1 January 2019, it became part of a new commune called Plateau d'Hauteville.