diff --git a/homeassistant/components/zestimate/sensor.py b/homeassistant/components/zestimate/sensor.py
index 036422d6800f5f..cb823dab0de7ae 100644
--- a/homeassistant/components/zestimate/sensor.py
+++ b/homeassistant/components/zestimate/sensor.py
@@ -66,6 +66,11 @@ def __init__(self, name, params):
         self.data = None
         self.address = None
         self._state = None
+ 
+    @property
+    def unique_id(self):
+        """Return the ZPID."""
+        return self.params['zpid']
 
     @property
     def name(self):