diff --git a/addons/sale_coupon/models/sale_coupon.py b/addons/sale_coupon/models/sale_coupon.py
index 522ce8362a2..934c1367e2f 100644
--- a/addons/sale_coupon/models/sale_coupon.py
+++ b/addons/sale_coupon/models/sale_coupon.py
@@ -46,6 +46,7 @@ class SaleCoupon(models.Model):
     ]
 
     def _compute_expiration_date(self):
+        self.expiration_date = 0
         for coupon in self.filtered(lambda x: x.program_id.validity_duration > 0):
             coupon.expiration_date = (coupon.create_date + relativedelta(days=coupon.program_id.validity_duration)).date()