diff --git a/.changeset/smart-jeans-repeat.md b/.changeset/smart-jeans-repeat.md
new file mode 100644
index 000000000000..28f6e61dc853
--- /dev/null
+++ b/.changeset/smart-jeans-repeat.md
@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+fix: default route config to `{}` for feature checking
diff --git a/packages/kit/src/core/postbuild/analyse.js b/packages/kit/src/core/postbuild/analyse.js
index ea2c0637dd2d..1cc928680e9a 100644
--- a/packages/kit/src/core/postbuild/analyse.js
+++ b/packages/kit/src/core/postbuild/analyse.js
@@ -97,7 +97,7 @@ async function analyse({ manifest_path, manifest_data, server_manifest, tracked_
 			}
 		}
 
-		const route_config = page?.config ?? endpoint?.config;
+		const route_config = page?.config ?? endpoint?.config ?? {};
 		const prerender = page?.prerender ?? endpoint?.prerender;
 
 		if (prerender !== true) {