diff --git a/mobile/android/base/NotificationHelper.java b/mobile/android/base/NotificationHelper.java
index d833f43862a..5d65792dafb 100644
--- a/mobile/android/base/NotificationHelper.java
+++ b/mobile/android/base/NotificationHelper.java
@@ -237,7 +237,7 @@ public final class NotificationHelper implements GeckoEventListener {
         builder.setOngoing(ongoing);
 
         if (message.has(WHEN_ATTR)) {
-            int when = message.optInt(WHEN_ATTR);
+            long when = message.optLong(WHEN_ATTR);
             builder.setWhen(when);
         }