diff --git a/moment-timezone/moment-timezone-tests.ts b/moment-timezone/moment-timezone-tests.ts
index d2cee664d..d01ea027c 100644
--- a/moment-timezone/moment-timezone-tests.ts
+++ b/moment-timezone/moment-timezone-tests.ts
@@ -77,3 +77,5 @@ moment.tz.load({
 moment.tz.names();
 
 moment.tz.setDefault('America/Los_Angeles');
+
+moment.tz.guess();