diff --git a/app/config/env/platformsh.php b/app/config/env/platformsh.php
index 699dfef39f..35b7084d93 100644
--- a/app/config/env/platformsh.php
+++ b/app/config/env/platformsh.php
@@ -37,7 +37,7 @@
 }
 
 // If mailer_host has default value, then set it to platform.sh' default instead
-if ($container->getParameter('mailer_host') === '127.0.0.1') {
+if ($container->resolveEnvPlaceholders($container->getParameter('mailer_host'), true) === '127.0.0.1') {
     $container->setParameter('mailer_host', getenv('PLATFORM_SMTP_HOST'));
 }