diff --git a/account_payment_order/models/account_payment_order.py b/account_payment_order/models/account_payment_order.py
index c241951c1..00d0ed03b 100644
--- a/account_payment_order/models/account_payment_order.py
+++ b/account_payment_order/models/account_payment_order.py
@@ -23,6 +23,7 @@ class AccountPaymentOrder(models.Model):
         required=True,
         ondelete="restrict",
         tracking=True,
+        readonly=True,
         states={"draft": [("readonly", False)]},
         check_company=True,
     )