diff --git a/.changeset/strong-cats-wonder.md b/.changeset/strong-cats-wonder.md
new file mode 100644
index 000000000000..2a1b29c9aa8c
--- /dev/null
+++ b/.changeset/strong-cats-wonder.md
@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+[fix] change Vite's output directory from `_app` to client
diff --git a/packages/kit/src/vite/build/build_server.js b/packages/kit/src/vite/build/build_server.js
index a36313acbc31..7094cdbd976b 100644
--- a/packages/kit/src/vite/build/build_server.js
+++ b/packages/kit/src/vite/build/build_server.js
@@ -73,7 +73,7 @@ export class Server {
 			manifest,
 			method_override: ${s(config.kit.methodOverride)},
 			paths: { base, assets },
-			prefix: assets + '/${config.kit.appDir}/',
+			prefix: assets + '/',
 			prerender: {
 				default: ${config.kit.prerender.default},
 				enabled: ${config.kit.prerender.enabled}
diff --git a/packages/kit/src/vite/build/build_service_worker.js b/packages/kit/src/vite/build/build_service_worker.js
index 4f4335a27f9e..9ae4441479e3 100644
--- a/packages/kit/src/vite/build/build_service_worker.js
+++ b/packages/kit/src/vite/build/build_service_worker.js
@@ -43,7 +43,7 @@ export async function build_service_worker(
 
 			export const build = [
 				${Array.from(build)
-					.map((file) => `${s(`${config.kit.paths.base}/${config.kit.appDir}/${file}`)}`)
+					.map((file) => `${s(`${config.kit.paths.base}/${file}`)}`)
 					.join(',\n\t\t\t\t')}
 			];
 
diff --git a/packages/kit/src/vite/build/utils.js b/packages/kit/src/vite/build/utils.js
index a82045414ac5..a0acb8771215 100644
--- a/packages/kit/src/vite/build/utils.js
+++ b/packages/kit/src/vite/build/utils.js
@@ -101,9 +101,9 @@ export const get_default_config = function ({ config, input, ssr, outDir }) {
 				input,
 				output: {
 					format: 'esm',
-					entryFileNames: ssr ? '[name].js' : 'immutable/[name]-[hash].js',
-					chunkFileNames: 'immutable/chunks/[name]-[hash].js',
-					assetFileNames: 'immutable/assets/[name]-[hash][extname]'
+					entryFileNames: ssr ? '[name].js' : `${config.kit.appDir}/immutable/[name]-[hash].js`,
+					chunkFileNames: `${config.kit.appDir}/immutable/chunks/[name]-[hash].js`,
+					assetFileNames: `${config.kit.appDir}/immutable/assets/[name]-[hash][extname]`
 				},
 				preserveEntrySignatures: 'strict'
 			},
@@ -145,7 +145,7 @@ export function assets_base(config) {
 	// during `svelte-kit preview`, because we use a local asset path. This
 	// may be fixed in Vite 3: https://github.com/vitejs/vite/issues/2009
 	const { base, assets } = config.paths;
-	return `${assets || base}/${config.appDir}/`;
+	return `${assets || base}/`;
 }
 
 /**
diff --git a/packages/kit/src/vite/index.js b/packages/kit/src/vite/index.js
index cd12cc85601a..08dc043cf598 100644
--- a/packages/kit/src/vite/index.js
+++ b/packages/kit/src/vite/index.js
@@ -180,7 +180,7 @@ function kit() {
 			paths = {
 				build_dir: `${svelte_config.kit.outDir}/build`,
 				output_dir: `${svelte_config.kit.outDir}/output`,
-				client_out_dir: `${svelte_config.kit.outDir}/output/client/${svelte_config.kit.appDir}`
+				client_out_dir: `${svelte_config.kit.outDir}/output/client/`
 			};
 
 			if (is_build) {
@@ -271,7 +271,7 @@ function kit() {
 			});
 
 			fs.writeFileSync(
-				`${paths.client_out_dir}/version.json`,
+				`${paths.client_out_dir}/${svelte_config.kit.appDir}/version.json`,
 				JSON.stringify({ version: svelte_config.kit.version.name })
 			);
 
@@ -316,8 +316,8 @@ function kit() {
 
 			const files = new Set([
 				...static_files,
-				...chunks.map((chunk) => `${svelte_config.kit.appDir}/${chunk.fileName}`),
-				...assets.map((chunk) => `${svelte_config.kit.appDir}/${chunk.fileName}`)
+				...chunks.map((chunk) => chunk.fileName),
+				...assets.map((chunk) => chunk.fileName)
 			]);
 
 			// TODO is this right?