diff --git a/prowler/providers/common/outputs.py b/prowler/providers/common/outputs.py
index 9b514999..8e6e994c 100644
--- a/prowler/providers/common/outputs.py
+++ b/prowler/providers/common/outputs.py
@@ -110,7 +110,7 @@ class Gcp_Output_Options(Provider_Output_Options):
             not hasattr(arguments, "output_filename")
             or arguments.output_filename is None
         ):
-            self.output_filename = f"prowler-output-{audit_info.default_project_id}-{output_file_timestamp}"
+            self.output_filename = f"prowler-output-{getattr(audit_info.credentials, '_service_account_email', 'default')}-{output_file_timestamp}"
         else:
             self.output_filename = arguments.output_filename
 
diff --git a/prowler/providers/gcp/gcp_provider.py b/prowler/providers/gcp/gcp_provider.py
index c75c599b..54a8f5f9 100644
--- a/prowler/providers/gcp/gcp_provider.py
+++ b/prowler/providers/gcp/gcp_provider.py
@@ -38,10 +38,6 @@ class GCP_Provider:
             # If not projects were input, all accessible projects are scanned by default
             self.project_ids = accessible_projects
 
-        # Set Default Project ID if not set in credentials
-        if not self.default_project_id:
-            self.default_project_id = self.project_ids[0]
-
     def __set_credentials__(self, credentials_file):
         try:
             if credentials_file: