diff --git a/ext/custom-addons/dp_custom/models/sale.py b/ext/custom-addons/dp_custom/models/sale.py
index 7c5760cb..e2167a5a 100644
--- a/ext/custom-addons/dp_custom/models/sale.py
+++ b/ext/custom-addons/dp_custom/models/sale.py
@@ -442,7 +442,7 @@ class SaleOrderLine(models.Model):
     @api.multi
     def calc_discount(self):
         discount = 0.0
-        context_partner = dict(self.env.context, partner_id=self.order_id.partner_id.id, date=self.order_id.date_order)
+        context_partner = dict(self.env.context, partner_id=self.order_id.partner_invoice_id.id, date=self.order_id.date_order)
         pricelist_context = dict(context_partner, uom=self.product_uom.id)
 
         price, rule_id = self.order_id.pricelist_id.with_context(pricelist_context).get_product_price_rule(