diff --git a/packages/next/src/build/webpack/plugins/next-types-plugin.ts b/packages/next/src/build/webpack/plugins/next-types-plugin.ts
index c10af295dd215..022e5e3e3aa17 100644
--- a/packages/next/src/build/webpack/plugins/next-types-plugin.ts
+++ b/packages/next/src/build/webpack/plugins/next-types-plugin.ts
@@ -371,6 +371,11 @@ export class NextTypesPlugin {
     if (!this.typedRoutes) return
 
     const isApp = filePath.startsWith(this.appDir + path.sep)
+    const isPages = !isApp && filePath.startsWith(this.pagesDir + path.sep)
+
+    if (!isApp && !isPages) {
+      return
+    }
 
     // Filter out non-page files in app dir
     if (isApp && !/[/\\]page\.[^.]+$/.test(filePath)) {
@@ -379,7 +384,7 @@ export class NextTypesPlugin {
 
     // Filter out non-page files in pages dir
     if (
-      !isApp &&
+      isPages &&
       /[/\\](?:_app|_document|_error|404|500)\.[^.]+$/.test(filePath)
     ) {
       return