diff --git a/tests/scripts/test_rename_sharepoint_files.py b/tests/scripts/test_rename_sharepoint_files.py
index b9d56562b..c732383c7 100644
--- a/tests/scripts/test_rename_sharepoint_files.py
+++ b/tests/scripts/test_rename_sharepoint_files.py
@@ -124,6 +124,33 @@ def test_run_renames_files_for_property_under_batch_root(tmp_path: Path) -> None
     sp.rename_file.assert_called_once_with("id-1", "100_1 High St AB1 2CD_Survey.pdf")
 
 
+def test_run_uprn_prefixed_address_yields_single_uprn_filename(
+    tmp_path: Path,
+) -> None:
+    # Arrange
+    csv_path = _write_csv(tmp_path, [("100", "100_1 High St", "AB1 2CD")])
+    batch_assessment = _assessment_path(
+        f"{BASE_PATH}/_Sero Batch 2", "100_1 High St", "AB1 2CD"
+    )
+
+    sp = MagicMock()
+
+    def fake_get(path: str) -> dict[str, Any]:
+        if path == BASE_PATH:
+            return {"value": [_make_folder("_Sero Batch 2")]}
+        if path == batch_assessment:
+            return {"value": [_make_file("Survey.pdf", "id-1")]}
+        raise ValueError("not found")
+
+    sp.get_folders_in_path.side_effect = fake_get
+
+    # Act
+    SharepointRenamerOrchestrator(sp, csv_path).run()
+
+    # Assert
+    sp.rename_file.assert_called_once_with("id-1", "100_1 High St AB1 2CD_Survey.pdf")
+
+
 # ---------------------------------------------------------------------------
 # _process_folder — files only at root level
 # ---------------------------------------------------------------------------