diff --git a/cbuildbot/stages/sync_stages.py b/cbuildbot/stages/sync_stages.py
index 5e41b0b..2c68f06 100644
--- a/cbuildbot/stages/sync_stages.py
+++ b/cbuildbot/stages/sync_stages.py
@@ -1393,7 +1393,12 @@
       cmd += ['-g', cros_patch.AddPrefix(patch, patch.gerrit_number)]
       self._PrintPatchStatus(patch, 'testing')
 
+    use_buildbucket = False
     config_buildbucket_id_map = {}
+    if buildbucket_lib.GetServiceAccount(constants.CHROMEOS_SERVICE_ACCOUNT):
+      # use buildbucket to launch trybots.
+      cmd += ['--use-buildbucket']
+      use_buildbucket = True
 
     if self._run.options.debug:
       logging.debug('Would have launched tryjob with %s', cmd)
@@ -1402,8 +1407,9 @@
           cmd, cwd=self._build_root, capture_output=True)
       if result and result.output:
         logging.info('cbuildbot output: %s' % result.output)
-        config_buildbucket_id_map = self.GetConfigBuildbucketIdMap(
-            result.output)
+        if use_buildbucket:
+          config_buildbucket_id_map = self.GetConfigBuildbucketIdMap(
+              result.output)
 
     actions = []
     build_id, db = self._run.GetCIDBHandle()
diff --git a/scripts/cbuildbot.py b/scripts/cbuildbot.py
index c1b863a..9b11aa3 100644
--- a/scripts/cbuildbot.py
+++ b/scripts/cbuildbot.py
@@ -479,8 +479,7 @@
       parser,
       'Remote Trybot Options (--remote)')
 
-  group.add_option('--do-not-use-buildbucket', action='store_false',
-                   dest='use_buildbucket', default=True,
+  group.add_option('--use-buildbucket', action='store_true', default=False,
                    help='Use buildbucket instead of git to request'
                         'the tryjob(s).')