diff --git a/releasenotes/notes/deprecate-and-enable-identity-application_credentials-1d4eaef4c3c9dcba.yaml b/releasenotes/notes/deprecate-and-enable-identity-application_credentials-1d4eaef4c3c9dcba.yaml
new file mode 100644
index 0000000..4b31ff8
--- /dev/null
+++ b/releasenotes/notes/deprecate-and-enable-identity-application_credentials-1d4eaef4c3c9dcba.yaml
@@ -0,0 +1,17 @@
+---
+upgrade:
+  - |
+    Application credentials are supported by Keystone since Queens.
+    As Tempest currently supports only much newer OpenStack versions
+    (Ussuri or later), the configuration option which enables
+    application credentials testing
+    (``CONF.identity-feature-enabled.application_credentials``)
+    is now enabled by default.
+deprecations:
+  - |
+    Application credentials are supported by Keystone since Queens.
+    As Tempest currently supports only much newer OpenStack versions
+    (Ussuri or later), the configuration option which enables
+    application credentials testing
+    (``CONF.identity-feature-enabled.application_credentials``)
+    is now deprecated.