diff --git a/homeassistant/components/sensor/postnl.py b/homeassistant/components/sensor/postnl.py
index 0e296fa56bd..9b35c1fdc7e 100644
--- a/homeassistant/components/sensor/postnl.py
+++ b/homeassistant/components/sensor/postnl.py
@@ -76,7 +76,7 @@ class PostNLSensor(Entity):
     @property
     def unit_of_measurement(self):
         """Return the unit of measurement of this entity, if any."""
-        return 'package(s)'
+        return 'packages'
 
     @property
     def device_state_attributes(self):