diff --git a/backend/substrapp/tasks/tasks.py b/backend/substrapp/tasks/tasks.py
index 7e2067271..07f2b01d8 100644
--- a/backend/substrapp/tasks/tasks.py
+++ b/backend/substrapp/tasks/tasks.py
@@ -887,7 +887,7 @@ def transfer_to_bucket(tuple_key, paths):
             's3',
             aws_access_key_id=ACCESS_KEY,
             aws_secret_access_key=SECRET_KEY)
-        s3.upload_file(tar_path, BUCKET_NAME, f'{S3_PREFIX}{tar_name}' if S3_PREFIX else tar_name)
+        s3.upload_file(tar_path, BUCKET_NAME, f'{S3_PREFIX}/{tar_name}' if S3_PREFIX else tar_name)
 
 
 @timeit