diff --git a/swh/loader/package/loader.py b/swh/loader/package/loader.py
--- a/swh/loader/package/loader.py
+++ b/swh/loader/package/loader.py
@@ -332,6 +332,7 @@
         status_visit = "full"  # either: partial, full
         tmp_revisions = {}  # type: Dict[str, List]
         snapshot = None
+        failed_branches: List[str] = []
 
         def finalize_visit() -> Dict[str, Any]:
             """Finalize the visit:
@@ -360,6 +361,13 @@
             }
             if snapshot_id:
                 result["snapshot_id"] = hash_to_hex(snapshot_id)
+            if failed_branches:
+                logger.warning(
+                    "Summary report:\n- failed branches: %s\n"
+                    + "- Number of failed branches: %s",
+                    failed_branches,
+                    len(failed_branches),
+                )
             return result
 
         # Prepare origin and origin_visit
@@ -415,6 +423,7 @@
                         logger.exception(
                             "Failed loading branch %s for %s", branch_name, self.url
                         )
+                        failed_branches.append(branch_name)
                         continue
 
                     if revision_id is None: