Coordinates: 47°46′59″N 7°20′55″E / 47.7831°N 7.3486°E / 47.7831; 7.3486
Illzach is a commune in the Haut-Rhin department in Alsace in north-eastern France.
It is located in the north side of the Mulhouse metropolitan area, and forms part of the Mulhouse Alsace Agglomération, the inter-communal local government body for that area.