diff --git a/src/storage/s3.js b/src/storage/s3.js
index 683a166a1..11d1b38ed 100644
--- a/src/storage/s3.js
+++ b/src/storage/s3.js
@@ -122,15 +122,6 @@ function upload(apiConfig, backupFilePath, sourceStream, callback) {
     assert.strictEqual(typeof sourceStream, 'object');
     assert.strictEqual(typeof callback, 'function');
 
-    function done(error) {
-        if (error) {
-            debug('[%s] upload: s3 upload error.', backupFilePath, error);
-            return callback(new BackupsError(BackupsError.EXTERNAL_ERROR, `Error uploading ${backupFilePath}. Message: ${error.message} HTTP Code: ${error.code}`));
-        }
-
-        callback(null);
-    }
-
     getS3Config(apiConfig, function (error, credentials) {
         if (error) return callback(error);
 
@@ -144,7 +135,14 @@ function upload(apiConfig, backupFilePath, sourceStream, callback) {
 
         // s3.upload automatically does a multi-part upload. we set queueSize to 1 to reduce memory usage
         // uploader will buffer at most queueSize * partSize bytes into memory at any given time.
-        return s3.upload(params, { partSize: 10 * 1024 * 1024, queueSize: 1 }, done);
+        return s3.upload(params, { partSize: 10 * 1024 * 1024, queueSize: 1 }, function (error) {
+            if (error) {
+                debug('[%s] upload: s3 upload error.', backupFilePath, error);
+                return callback(new BackupsError(BackupsError.EXTERNAL_ERROR, `Error uploading ${backupFilePath}. Message: ${error.message} HTTP Code: ${error.code}`));
+            }
+
+            callback(null);
+        });
     });
 }