diff --git a/homeassistant/components/sonos/speaker.py b/homeassistant/components/sonos/speaker.py
index 0d7efae1877..3932b6d3364 100644
--- a/homeassistant/components/sonos/speaker.py
+++ b/homeassistant/components/sonos/speaker.py
@@ -372,7 +372,8 @@ class SonosSpeaker:
     @callback
     def async_dispatch_alarms(self, event: SonosEvent) -> None:
         """Create a task to update alarms from an event."""
-        update_id = event.variables["alarm_list_version"]
+        if not (update_id := event.variables.get("alarm_list_version")):
+            return
         if update_id in self.processed_alarm_events:
             return
         self.processed_alarm_events.append(update_id)