diff --git a/models/sale.py b/models/sale.py
index 10e0ce653c82f2c2348bb1344ad847e4d0274d89..c2f562da2af7843b7f11acafc3f9333a30b6f07a 100644
--- a/models/sale.py
+++ b/models/sale.py
@@ -17,11 +17,14 @@ class SaleOrder(models.Model):
         Compute the amount (untaxed) that remains to be invoiced from sale order
         """
         for order in self:
-            line_to_invoice = [line for line in order.order_line if line.invoice_status == 'to invoice' or line.invoice_status == 'invoiced']
+            if order.invoice_status == ('to invoice'):
+                line_to_invoice = [line for line in order.order_line if line.invoice_status != 'no']
 
-            untaxed_amount_to_invoice = order.amount_untaxed 
-            for line in line_to_invoice:
-                untaxed_amount_to_invoice -= line.qty_invoiced * line.price_unit
+                untaxed_amount_to_invoice = order.amount_untaxed 
+                for line in line_to_invoice:
+                    untaxed_amount_to_invoice -= line.qty_invoiced * line.price_unit
+            else:
+                untaxed_amount_to_invoice = 0.0
 
             order.update({
                 'untaxed_amount_to_invoice': untaxed_amount_to_invoice