diff --git a/modules/product_kit/purchase.py b/modules/product_kit/purchase.py
index ad83343e66..295f4bebf5 100644
--- a/modules/product_kit/purchase.py
+++ b/modules/product_kit/purchase.py
@@ -1,5 +1,8 @@
 # This file is part of Tryton.  The COPYRIGHT file at the top level of
 # this repository contains the full copyright notices and license terms.
+
+from decimal import Decimal
+
 from trytond.i18n import gettext
 from trytond.model import ModelSQL, ModelView, fields
 from trytond.modules.product import round_price
@@ -59,7 +62,10 @@ class Line(order_line_mixin('purchase'), metaclass=PoolMeta):
     def get_component_order_line(self, component, **values):
         values = values.copy()
         values['purchase'] = self.purchase
-        return super().get_component_order_line(component, **values)
+        line = super().get_component_order_line(component, **values)
+        if line.unit_price is None:
+            line.unit_price = round_price(Decimal(0))
+        return line
 
     @classmethod
     def get_move_product_types(cls):
diff --git a/modules/product_kit/tests/scenario_product_kit_purchase.rst b/modules/product_kit/tests/scenario_product_kit_purchase.rst
index de61196bc7..665583ea22 100644
--- a/modules/product_kit/tests/scenario_product_kit_purchase.rst
+++ b/modules/product_kit/tests/scenario_product_kit_purchase.rst
@@ -259,7 +259,7 @@ Check unit price of moves::
     >>> shipment.reload()
     >>> invoice.reload()
     >>> sorted([m.unit_price for m in shipment.incoming_moves])
-    [Decimal('5.0000'), Decimal('5.0000'), Decimal('9.4545'), Decimal('14.1818')]
+    [Decimal('0.0000'), Decimal('5.0000'), Decimal('9.4545'), Decimal('14.1818')]
 
 Check backorder moves::
 
diff --git a/modules/production_outsourcing/production.py b/modules/production_outsourcing/production.py
index c59bbb050d..6fccb8b9e6 100644
--- a/modules/production_outsourcing/production.py
+++ b/modules/production_outsourcing/production.py
@@ -1,5 +1,7 @@
 # This file is part of Tryton.  The COPYRIGHT file at the top level of
 # this repository contains the full copyright notices and license terms.
+
+from decimal import Decimal
 from itertools import groupby
 
 from trytond.i18n import gettext
@@ -215,6 +217,8 @@ class Production(metaclass=PoolMeta):
             factor * self.routing.supplier_quantity)
         line.purchase = purchase
         line.on_change_product()
+        if line.unit_price is None:
+            line.unit_price = round_price(Decimal(0))
         return line
 
     @classmethod