diff --git a/models/res_partner.py b/models/res_partner.py
index c9d43f4ebf626a1d501b35ada18f220c27eec5d4..e78c129fb16a2f407a05f0f48409c6adabbf49b7 100644
--- a/models/res_partner.py
+++ b/models/res_partner.py
@@ -503,7 +503,8 @@ class ScopPartner(models.Model):
 
     @api.onchange('parent_id')
     def _onchange_parent_id(self):
-        self.ur_id = self.parent_id.ur_id
+        if self.parent_id.ur_id:
+            self.ur_id = self.parent_id.ur_id
 
     @api.onchange('ur_id')
     def _onchange_ur_id(self):