diff --git a/src/storage/src/storage3/_async/file_api.py b/src/storage/src/storage3/_async/file_api.py
index ca8aaab6..4993671a 100644
--- a/src/storage/src/storage3/_async/file_api.py
+++ b/src/storage/src/storage3/_async/file_api.py
@@ -111,7 +111,7 @@ async def create_signed_upload_url(
         )
         data = response.json()
         full_url: urllib.parse.ParseResult = urllib.parse.urlparse(
-            str(self._client.base_url) + cast(str, data["url"]).lstrip("/")
+            str(self._base_url) + cast(str, data["url"]).lstrip("/")
         )
         query_params = urllib.parse.parse_qs(full_url.query)
         if not query_params.get("token"):
diff --git a/src/storage/src/storage3/_sync/file_api.py b/src/storage/src/storage3/_sync/file_api.py
index 6864366e..b1be7bcc 100644
--- a/src/storage/src/storage3/_sync/file_api.py
+++ b/src/storage/src/storage3/_sync/file_api.py
@@ -111,7 +111,7 @@ def create_signed_upload_url(
         )
         data = response.json()
         full_url: urllib.parse.ParseResult = urllib.parse.urlparse(
-            str(self._client.base_url) + cast(str, data["url"]).lstrip("/")
+            str(self._base_url) + cast(str, data["url"]).lstrip("/")
         )
         query_params = urllib.parse.parse_qs(full_url.query)
         if not query_params.get("token"):
diff --git a/src/storage/tests/_async/test_client.py b/src/storage/tests/_async/test_client.py
index ed041a60..85abddc2 100644
--- a/src/storage/tests/_async/test_client.py
+++ b/src/storage/tests/_async/test_client.py
@@ -322,7 +322,7 @@ async def test_client_create_signed_upload_url(
     data = await storage_file_client.create_signed_upload_url(path)
     assert data["path"] == path
     assert data["token"]
-    expected_url = f"{storage_file_client._client.base_url}object/upload/sign/{storage_file_client.id}/{path.lstrip('/')}"
+    expected_url = f"{storage_file_client._base_url}object/upload/sign/{storage_file_client.id}/{path.lstrip('/')}"
     assert data["signed_url"].startswith(expected_url)
 
 
diff --git a/src/storage/tests/_sync/test_client.py b/src/storage/tests/_sync/test_client.py
index 51f09e76..b549db0f 100644
--- a/src/storage/tests/_sync/test_client.py
+++ b/src/storage/tests/_sync/test_client.py
@@ -322,7 +322,7 @@ def test_client_create_signed_upload_url(
     data = storage_file_client.create_signed_upload_url(path)
     assert data["path"] == path
     assert data["token"]
-    expected_url = f"{storage_file_client._client.base_url}object/upload/sign/{storage_file_client.id}/{path.lstrip('/')}"
+    expected_url = f"{storage_file_client._base_url}object/upload/sign/{storage_file_client.id}/{path.lstrip('/')}"
     assert data["signed_url"].startswith(expected_url)