diff --git a/lib/builder/webpack/client.config.js b/lib/builder/webpack/client.config.js
index b287a67aab..6f5db0d48c 100644
--- a/lib/builder/webpack/client.config.js
+++ b/lib/builder/webpack/client.config.js
@@ -48,7 +48,7 @@ export default function webpackClientConfig () {
         }
 
         // Total pages
-        const totalPages = _this.routes.length
+        const totalPages = _this.routes ? _this.routes.length : 0
 
         // A module is extracted into the vendor chunk when...
         return (