diff --git a/tosfs/core.py b/tosfs/core.py
index 1533f5f..21e1860 100644
--- a/tosfs/core.py
+++ b/tosfs/core.py
@@ -34,6 +34,7 @@
     ListObjectType2Output,
     ListObjectVersionsOutput,
     PartInfo,
+    UploadPartCopyOutput,
     UploadPartOutput,
 )
 
@@ -1203,8 +1204,8 @@ def _call_upload_part_copy(
                     i: int = i,
                     brange_first: int = brange_first,
                     brange_last: int = brange_last,
-                ) -> None:
-                    self.tos_client.upload_part_copy(
+                ) -> UploadPartCopyOutput:
+                    return self.tos_client.upload_part_copy(
                         bucket=bucket2,
                         key=key2,
                         part_number=i,
@@ -1279,8 +1280,8 @@ def _copy_managed(
 
             def _call_upload_part_copy(
                 i: int, brange_first: int, brange_last: int
-            ) -> None:
-                self.tos_client.upload_part_copy(
+            ) -> UploadPartCopyOutput:
+                return self.tos_client.upload_part_copy(
                     bucket=bucket2,
                     key=key2,
                     part_number=i + 1,