diff --git a/contract/models/contract_line.py b/contract/models/contract_line.py
index 40c4d657..3178f240 100644
--- a/contract/models/contract_line.py
+++ b/contract/models/contract_line.py
@@ -24,6 +24,7 @@ class ContractLine(models.Model):
         string='Contract',
         required=True,
         index=True,
+        auto_join=True,
         ondelete='cascade',
     )
     analytic_account_id = fields.Many2one(