diff --git a/core/lib/Drupal/Core/Field/PluginSettingsInterface.php b/core/lib/Drupal/Core/Field/PluginSettingsInterface.php
index cc64850..e98e6c4c 100644
--- a/core/lib/Drupal/Core/Field/PluginSettingsInterface.php
+++ b/core/lib/Drupal/Core/Field/PluginSettingsInterface.php
@@ -11,6 +11,9 @@
 
 /**
  * Interface definition for plugin with settings.
+ *
+ * @deprecated Deprecated as of 8.0.0. Scheduled for removal in 9.0.0. Use
+ *   \Drupal\Component\Plugin\ConfigurablePluginInterface instead.
  */
 interface PluginSettingsInterface extends PluginInspectionInterface {