diff --git a/app/broadcast_areas/models.py b/app/broadcast_areas/models.py
index 271da834f..8d364e3c5 100644
--- a/app/broadcast_areas/models.py
+++ b/app/broadcast_areas/models.py
@@ -86,6 +86,14 @@ class BroadcastArea(BaseBroadcastArea, SortableMixin):
     def __init__(self, row):
         self.id, self.name, self._count_of_phones, self.library_id = row
 
+    @cached_property
+    def is_lower_tier_local_authority(self):
+        return self.id.startswith('lad20-') and self.parent
+
+    @cached_property
+    def is_electoral_ward(self):
+        return self.id.startswith('wd20-')
+
     @classmethod
     def from_row_with_simple_polygons(cls, row):
         instance = cls(row[:4])
diff --git a/app/broadcast_areas/utils.py b/app/broadcast_areas/utils.py
index fdcc1f83a..217bf028e 100644
--- a/app/broadcast_areas/utils.py
+++ b/app/broadcast_areas/utils.py
@@ -24,7 +24,7 @@ def _convert_custom_areas_to_wards(areas):
 
 def _aggregate_wards_by_local_authority(areas):
     return {
-        area.parent if area.id.startswith('wd20-')
+        area.parent if area.is_electoral_ward
         else area for area in areas
     }
 
@@ -56,7 +56,7 @@ def _cluster_lower_tier_authorities(areas):
 
     for area in areas:
         # group lower tier authorities by "county"
-        if area.id.startswith('lad20-') and area.parent:
+        if area.is_lower_tier_local_authority:
             result[area.parent] += [area]
         # leave countries, unitary authorities as-is
         else: