diff --git a/bbp-includes/common/functions.php b/bbp-includes/common/functions.php
index 6a28e80..7e648bf 100644
--- a/bbp-includes/common/functions.php
+++ b/bbp-includes/common/functions.php
@@ -970,6 +970,9 @@
 	if ( !bbp_is_subscriptions_active() )
 		return false;
 
+	/** Headers ***************************************************************/
+	$headers = apply_filters( 'bbp_mail_headers', $headers );
+
 	/** Validation ************************************************************/
 
 	$reply_id = bbp_get_reply_id( $reply_id );
@@ -1051,7 +1054,7 @@
 		$user = get_userdata( $user_id );
 
 		// Send notification email
-		wp_mail( $user->user_email, $subject, $message );
+		wp_mail( $user->user_email, $subject, $message, $headers );
 	}
 
 	do_action( 'bbp_post_notify_subscribers', $reply_id, $topic_id, $user_ids );