diff --git a/addons/sale/models/sale.py b/addons/sale/models/sale.py
index 6c698a35169..9a6b63a7d13 100644
--- a/addons/sale/models/sale.py
+++ b/addons/sale/models/sale.py
@@ -1578,7 +1578,7 @@ class SaleOrderLine(models.Model):
             if currency_id.id == product_currency.id:
                 cur_factor = 1.0
             else:
-                cur_factor = currency_id._get_conversion_rate(product_currency, currency_id, self.company_id, self.order_id.date_order)
+                cur_factor = currency_id._get_conversion_rate(product_currency, currency_id, self.company_id or self.env.user.company_id, self.order_id.date_order or fields.Date.today())
 
         product_uom = self.env.context.get('uom') or product.uom_id.id
         if uom and uom.id != product_uom: