diff --git a/src/Bundle/ChillMainBundle/DependencyInjection/Configuration.php b/src/Bundle/ChillMainBundle/DependencyInjection/Configuration.php
index 8f70d2604..ad4c1929b 100644
--- a/src/Bundle/ChillMainBundle/DependencyInjection/Configuration.php
+++ b/src/Bundle/ChillMainBundle/DependencyInjection/Configuration.php
@@ -43,6 +43,7 @@ class Configuration implements ConfigurationInterface
             ->children()
             ->scalarNode('phonenumber_default_country_code')
             ->cannotBeEmpty()
+            ->isRequired()
             ->defaultValue('+32')
             ->end() // end of scalar 'phonenumber_default_country_code'
             ->scalarNode('installation_name')