The Deux-Montagnes / Ste-Marthe-sur-le-lac Fire Service is part of a 11 service mutual aid. The following is a list of departments that are in the mutual aid system.

• Deux-Montagnes/Ste-Marthe-sur-le-lac
• St-Eustache
• Mirabel
• Boisbriand
• Ste-Thérèse
• Rosemere
• Blainville
• Ste-Anne-Des-Plaines
• St-Antoine
• Bellefeuille
• St-Jerôme