diff --git a/lib/file_transfer_agent/gcs_util.js b/lib/file_transfer_agent/gcs_util.js
index b72d9ef91..3cf6a0e2b 100644
--- a/lib/file_transfer_agent/gcs_util.js
+++ b/lib/file_transfer_agent/gcs_util.js
@@ -178,7 +178,7 @@ function GCSUtil(httpclient, filestream) {
             encryptionMetadata
           );
         } catch (err) {
-          const errCode = err['code'] ? err['code'] : err.response.status;
+          const errCode = !isNaN(err['code']) && !isNaN(parseInt(err['code'])) ? err['code'] : err.response.status;
 
           if ([403, 408, 429, 500, 503].includes(errCode)) {
             meta['lastError'] = err;