diff --git a/backend/condition/lookups/uprn_lookup_csv.py b/backend/condition/lookups/uprn_lookup_csv.py
new file mode 100644
index 00000000..5f84587a
--- /dev/null
+++ b/backend/condition/lookups/uprn_lookup_csv.py
@@ -0,0 +1,9 @@
+from typing import BinaryIO, Dict
+from backend.condition.lookups.uprn_lookup import UprnLookup
+
+
+class UprnLookupCsv(UprnLookup):
+    def get_location_ref_to_uprn_map(
+        self, lookup_file_stream: BinaryIO
+    ) -> Dict[str, int]:
+        raise NotImplementedError
diff --git a/backend/condition/lookups/uprn_lookup_local.py b/backend/condition/lookups/uprn_lookup_local.py
deleted file mode 100644
index 7bf7a575..00000000
--- a/backend/condition/lookups/uprn_lookup_local.py
+++ /dev/null
@@ -1,7 +0,0 @@
-from typing import Dict
-from backend.condition.lookups.uprn_lookup import UprnLookup
-
-
-class UprnLookupLocal(UprnLookup):
-    def get_location_ref_to_uprn_map(self, lookup_filepath: str) -> Dict[str, int]:
-        raise NotImplementedError
diff --git a/backend/condition/lookups/uprn_lookup_s3.py b/backend/condition/lookups/uprn_lookup_s3.py
deleted file mode 100644
index e73bffaf..00000000
--- a/backend/condition/lookups/uprn_lookup_s3.py
+++ /dev/null
@@ -1,7 +0,0 @@
-from typing import Dict
-from backend.condition.lookups.uprn_lookup import UprnLookup
-
-
-class UprnLookupS3(UprnLookup):
-    def get_location_ref_to_uprn_map(self, lookup_filepath: str) -> Dict[str, int]:
-        raise NotImplementedError
diff --git a/backend/condition/tests/lookups/test_uprn_lookup_csv.py b/backend/condition/tests/lookups/test_uprn_lookup_csv.py
new file mode 100644
index 00000000..67cb80b9
--- /dev/null
+++ b/backend/condition/tests/lookups/test_uprn_lookup_csv.py
@@ -0,0 +1,33 @@
+from typing import Any, Dict
+import pytest
+from io import BytesIO
+
+from backend.condition.lookups.uprn_lookup_csv import UprnLookupCsv
+
+
+@pytest.fixture
+def prop_ref_uprn_csv_bytes() -> BytesIO:
+    csv_bytes = b"""reference, out_uprn
+    ABC123,10000000001
+    DEF456,10000000002
+    GHI789,10000000003
+    """
+    return BytesIO(csv_bytes)
+
+
+def test_generate_prop_ref_uprn_from_csv_bytes(prop_ref_uprn_csv_bytes) -> None:
+    # arrange
+    uprn_lookup = UprnLookupCsv()
+    expected_map: Dict[str, int] = {
+        "ABC123": 10000000001,
+        "DEF456": 10000000002,
+        "GHI789": 10000000003,
+    }
+
+    # act
+    actual_map: Dict[str, int] = uprn_lookup.get_location_ref_to_uprn_map(
+        prop_ref_uprn_csv_bytes
+    )
+
+    # assert
+    assert actual_map == expected_map