Wattrelos is a commune in the Nord department in the Hauts-de-France region of northern France. It is located on the border with Belgium, northeast of the city of Lille. The fifth-largest component of the Métropole Européenne de Lille, Wattrelos borders the communes of Roubaix, Tourcoing and Leers in France and the communes of Mouscron and Estaimpuis in Belgium.