diff --git a/addons/point_of_sale/models/pos_order.py b/addons/point_of_sale/models/pos_order.py
index 7a662a7d722..061e381438e 100644
--- a/addons/point_of_sale/models/pos_order.py
+++ b/addons/point_of_sale/models/pos_order.py
@@ -1228,7 +1228,7 @@ class PosOrder(models.Model):
             'partner_id': order.partner_id.id,
             'user_id': order.user_id.id,
             'sequence_number': order.sequence_number,
-            'creation_date': order.date_order.astimezone(timezone),
+            'creation_date': str(order.date_order.astimezone(timezone)),
             'fiscal_position_id': order.fiscal_position_id.id,
             'to_invoice': order.to_invoice,
             'shipping_date': order.shipping_date,