diff --git a/src/Elasticsearch/ClientBuilder.php b/src/Elasticsearch/ClientBuilder.php
index 1b09d6556..91a9e0a75 100644
--- a/src/Elasticsearch/ClientBuilder.php
+++ b/src/Elasticsearch/ClientBuilder.php
@@ -401,6 +401,7 @@ public function setSSLVerification($value = true)
     public function allowBadJSONSerialization()
     {
         $this->allowBadJSON = true;
+        return $this;
     }
 
     /**