diff --git a/etl/transform/types.py b/etl/transform/types.py
index f8fe9e6..896fc4f 100644
--- a/etl/transform/types.py
+++ b/etl/transform/types.py
@@ -29,7 +29,7 @@ class SurverySummaryInfo(BaseModel):
     region: str
     address: str
     town: str
-    county: Optional[str] = None
+    county: Optional[str] = ""
     property_tenure: str
     transaction_type: str
     inspection_date: datetime