diff --git a/apps/pigment-css-next-app/next.config.mjs b/apps/pigment-css-next-app/next.config.mjs
index 07d6db2035c912..86ce5e7e966b74 100644
--- a/apps/pigment-css-next-app/next.config.mjs
+++ b/apps/pigment-css-next-app/next.config.mjs
@@ -1,5 +1,4 @@
 /* eslint-env node */
-// eslint-ignore-next-line import/no-unresolved
 import { withPigment } from '@pigment-css/nextjs-plugin';
 import { extendTheme } from '@mui/material/styles';
 
diff --git a/examples/material-ui-nextjs-pages-router-ts/next.config.js b/examples/material-ui-nextjs-pages-router-ts/next.config.mjs
similarity index 78%
rename from examples/material-ui-nextjs-pages-router-ts/next.config.js
rename to examples/material-ui-nextjs-pages-router-ts/next.config.mjs
index 3dd7ef15191a9f..dffddd8c9e3ec9 100644
--- a/examples/material-ui-nextjs-pages-router-ts/next.config.js
+++ b/examples/material-ui-nextjs-pages-router-ts/next.config.mjs
@@ -1,4 +1,4 @@
 /** @type {import('next').NextConfig} */
-module.exports = {
+export default {
   reactStrictMode: true,
 };
diff --git a/examples/material-ui-nextjs-pages-router/next.config.js b/examples/material-ui-nextjs-pages-router/next.config.mjs
similarity index 59%
rename from examples/material-ui-nextjs-pages-router/next.config.js
rename to examples/material-ui-nextjs-pages-router/next.config.mjs
index da1bb770fb8e60..4d496ef6bb1988 100644
--- a/examples/material-ui-nextjs-pages-router/next.config.js
+++ b/examples/material-ui-nextjs-pages-router/next.config.mjs
@@ -1,3 +1,3 @@
-module.exports = {
+export default {
   reactStrictMode: true,
 };
diff --git a/examples/material-ui-nextjs-ts-v4-v5-migration/next.config.js b/examples/material-ui-nextjs-ts-v4-v5-migration/next.config.mjs
similarity index 78%
rename from examples/material-ui-nextjs-ts-v4-v5-migration/next.config.js
rename to examples/material-ui-nextjs-ts-v4-v5-migration/next.config.mjs
index 3dd7ef15191a9f..dffddd8c9e3ec9 100644
--- a/examples/material-ui-nextjs-ts-v4-v5-migration/next.config.js
+++ b/examples/material-ui-nextjs-ts-v4-v5-migration/next.config.mjs
@@ -1,4 +1,4 @@
 /** @type {import('next').NextConfig} */
-module.exports = {
+export default {
   reactStrictMode: true,
 };
diff --git a/test/bundling/fixtures/next-webpack4/next.config.js b/test/bundling/fixtures/next-webpack4/next.config.mjs
similarity index 92%
rename from test/bundling/fixtures/next-webpack4/next.config.js
rename to test/bundling/fixtures/next-webpack4/next.config.mjs
index 2e0d198c8f3565..18bac177216d05 100644
--- a/test/bundling/fixtures/next-webpack4/next.config.js
+++ b/test/bundling/fixtures/next-webpack4/next.config.mjs
@@ -1,4 +1,4 @@
-module.exports = {
+export default {
   webpack5: false,
   eslint: {
     ignoreDuringBuilds: true,
diff --git a/test/bundling/fixtures/next-webpack5/next.config.js b/test/bundling/fixtures/next-webpack5/next.config.mjs
similarity index 72%
rename from test/bundling/fixtures/next-webpack5/next.config.js
rename to test/bundling/fixtures/next-webpack5/next.config.mjs
index 7d17dcfcfb4d45..565c49645e3487 100644
--- a/test/bundling/fixtures/next-webpack5/next.config.js
+++ b/test/bundling/fixtures/next-webpack5/next.config.mjs
@@ -1,4 +1,4 @@
-module.exports = {
+export default {
   eslint: {
     ignoreDuringBuilds: true,
   },