Cortanze is a comune (municipality) in the Province of Asti in the Italian region Piedmont, located about east of Turin and about northwest of Asti. As of 31 january 2024, it had a population of 258 and an area of .
The municipality of Cortanze contains the frazioni (subdivisions, mainly villages and hamlets) Roera and San Rocco.
Cortanze borders the following municipalities: Cunico, Montechiaro dâÂÂAsti, Piea, Soglio, and Viale.