diff --git a/repositories/historic_epc/historic_epc_s3_repository.py b/repositories/historic_epc/historic_epc_s3_repository.py
index bc2d5dcca..ce735802e 100644
--- a/repositories/historic_epc/historic_epc_s3_repository.py
+++ b/repositories/historic_epc/historic_epc_s3_repository.py
@@ -10,7 +10,10 @@ from datatypes.epc.domain.historic_epc_matching import (
     _map_historic_epc_pandas_row_to_domain,
     _sanitise_postcode,
 )
-from repositories.historic_epc.historic_epc_repository import HistoricEpcRepository
+from repositories.historic_epc.historic_epc_repository import (
+    HistoricEpcRepository,
+    PostcodeNotFound,
+)
 from utils.s3 import parse_s3_uri, read_csv_gz_from_s3
 
 DEFAULT_S3_ROOT = "s3://retrofit-data-dev/historical_epc"
@@ -33,7 +36,10 @@ class HistoricEpcS3Repository(HistoricEpcRepository):
         self._s3_root = s3_root
 
     def get_for_postcode(self, postcode: str) -> list[HistoricEpc]:
-        pc = _sanitise_postcode(postcode)
+        try:
+            pc = _sanitise_postcode(postcode)
+        except ValueError as e:
+            raise PostcodeNotFound(str(e)) from e
         bucket, root_prefix = parse_s3_uri(self._s3_root)
         key = f"{root_prefix.rstrip('/')}/{pc}/data.csv.gz"
         try: