diff --git a/Controller.php b/Controller.php
index 9e7b8c5..0e1d5e1 100644
--- a/Controller.php
+++ b/Controller.php
@@ -60,6 +60,14 @@ class Controller extends ModuleAbstract implements WebInterface
      */
     /* public */ const MODULE_NAME = 'Billing';
 
+    /**
+     * Module id.
+     *
+     * @var int
+     * @since 1.0.0
+     */
+    /* public */ const MODULE_ID = 1005100000;
+
     /**
      * Providing.
      *