diff -u b/core/modules/migrate/src/Plugin/Migration.php b/core/modules/migrate/src/Plugin/Migration.php
--- b/core/modules/migrate/src/Plugin/Migration.php
+++ b/core/modules/migrate/src/Plugin/Migration.php
@@ -16,11 +16,6 @@
  * The migration process plugin represents one single migration and acts like a
  * container for the information about a single migration such as the source,
  * process and destination plugins.
- *
- * Configuration options:
- * - audit: If set to TRUE, the migration's IDs will be audited. This means
- *   that if the highest destination ID is greater than the highest source ID,
- *   a warning will be displayed that entities might be overwritten.
  */
 class Migration extends PluginBase implements MigrationInterface, RequirementsInterface, ContainerFactoryPluginInterface {
 
@@ -160,6 +155,17 @@
   protected $migration_tags = [];
 
   /**
+   * Whether the migration is auditable.
+   *
+   * If set to TRUE, the migration's IDs will be audited. This means that, if
+   * the highest destination ID is greater than the highest source ID, a warning
+   * will be displayed that entities might be overwritten.
+   *
+   * @var bool
+   */
+  protected $audit = FALSE;
+
+  /**
    * These migrations, if run, must be executed before this migration.
    *
    * These are different from the configuration dependencies. Migration