diff --git a/src/TransactionBuilder.php b/src/TransactionBuilder.php
index ae78ab1..8777ed7 100644
--- a/src/TransactionBuilder.php
+++ b/src/TransactionBuilder.php
@@ -134,6 +134,18 @@ public function withBusinessIdentificationNo($no)
         return $this;
     }
 
+    /**
+     * Set a customer email
+     *
+     * @param   string              email
+     * @return  TransactionBuilder
+     */
+    public function withEmail($email)
+    {
+        $this->_model['email'] = $email;
+        return $this;
+    }
+
     /**
      * Set client application customer or usage type
      *