diff --git a/homeassistant/components/sensor/tellduslive.py b/homeassistant/components/sensor/tellduslive.py
index 7d67dcfb38f..1d662cd8e84 100644
--- a/homeassistant/components/sensor/tellduslive.py
+++ b/homeassistant/components/sensor/tellduslive.py
@@ -146,4 +146,4 @@ class TelldusLiveSensor(TelldusLiveEntity):
     @property
     def unique_id(self) -> str:
         """Return a unique ID."""
-        return "-".join(self._id[0:2])
+        return "-".join(map(str, self._id))