Valmacca is a comune, or municipality, located in the Piedmont region of northern Italy. It falls within the Province of Alessandria and is situated in a plain area on the right bank of the Po River.
The town is positioned at the confluence of the Rotaldo and Gattola rivers. Geographically, it lies approximately 70 kilometres east of Turin and about 20 kilometres north of the city of Alessandria.