diff --git a/lib/utils/place-outdial.js b/lib/utils/place-outdial.js
index c26e9394..0e08b3bc 100644
--- a/lib/utils/place-outdial.js
+++ b/lib/utils/place-outdial.js
@@ -325,7 +325,7 @@ class SingleDialer extends Emitter {
       this.logger.debug('SingleDialer:kill hanging up called party');
       this.emit('callStatusChange', {callStatus: CallStatus.Completed, duration});
       const headers = {
-        ...(Reason && {Reason})
+        ...(Reason && {'X-Reason': Reason})
       };
       this.dlg.destroy({
         headers