diff --git a/appstore/notification.go b/appstore/notification.go
index 939909a..f629ee4 100644
--- a/appstore/notification.go
+++ b/appstore/notification.go
@@ -21,6 +21,9 @@ const (
 	NotificationTypeDidChangeRenewalStatus NotificationType = "DID_CHANGE_RENEWAL_STATUS"
 	// Subscription failed to renew due to a billing issue.
 	NotificationTypeDidFailToRenew NotificationType = "DID_FAIL_TO_RENEW"
+	// Indicates that App Store successfully refunded a transaction
+	NotificationTypeRefund NotificationType = "REFUND"
+
 )
 
 type NotificationEnvironment string