diff --git a/.changeset/slow-gorillas-yawn.md b/.changeset/slow-gorillas-yawn.md
new file mode 100644
index 0000000000..376b4d041c
--- /dev/null
+++ b/.changeset/slow-gorillas-yawn.md
@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+breaking: avoid flushing queued updates on mount/hydrate
diff --git a/packages/svelte/src/internal/client/render.js b/packages/svelte/src/internal/client/render.js
index 21cc096325..a3895ac331 100644
--- a/packages/svelte/src/internal/client/render.js
+++ b/packages/svelte/src/internal/client/render.js
@@ -79,8 +79,7 @@ export function set_text(text, value) {
  */
 export function mount(component, options) {
 	const anchor = options.anchor ?? options.target.appendChild(empty());
-	// Don't flush previous effects to ensure order of outer effects stays consistent
-	return flush_sync(() => _mount(component, { ...options, anchor }), false);
+	return _mount(component, { ...options, anchor });
 }
 
 /**
diff --git a/packages/svelte/tests/runtime-browser/samples/bind-playbackrate/_config.js b/packages/svelte/tests/runtime-browser/samples/bind-playbackrate/_config.js
index c2718e2850..c94ad0ee3c 100644
--- a/packages/svelte/tests/runtime-browser/samples/bind-playbackrate/_config.js
+++ b/packages/svelte/tests/runtime-browser/samples/bind-playbackrate/_config.js
@@ -1,8 +1,10 @@
+import { flushSync } from 'svelte';
 import { test, ok } from '../../assert';
 
 export default test({
 	mode: ['client'],
 	async test({ assert, target }) {
+		flushSync();
 		const audio = target.querySelector('audio');
 		const button = target.querySelector('button');
 		ok(audio);
diff --git a/packages/svelte/tests/runtime-browser/samples/head-script/_config.js b/packages/svelte/tests/runtime-browser/samples/head-script/_config.js
index b40d4e22e2..ba2680cac1 100644
--- a/packages/svelte/tests/runtime-browser/samples/head-script/_config.js
+++ b/packages/svelte/tests/runtime-browser/samples/head-script/_config.js
@@ -1,7 +1,9 @@
+import { flushSync } from 'svelte';
 import { test } from '../../assert';
 
 export default test({
 	test({ assert, window }) {
+		flushSync();
 		document.dispatchEvent(new Event('DOMContentLoaded'));
 		assert.equal(window.document.querySelector('button')?.textContent, 'Hello world');
 	}
diff --git a/packages/svelte/tests/runtime-browser/samples/sole-script-tag/_config.js b/packages/svelte/tests/runtime-browser/samples/sole-script-tag/_config.js
index 650e9241ea..bc81a48fb1 100644
--- a/packages/svelte/tests/runtime-browser/samples/sole-script-tag/_config.js
+++ b/packages/svelte/tests/runtime-browser/samples/sole-script-tag/_config.js
@@ -1,3 +1,4 @@
+import { flushSync } from 'svelte';
 import { test } from '../../assert';
 
 export default test({
@@ -5,6 +6,7 @@ export default test({
 	// Needs to be in this test suite because JSDOM does not quite get this right.
 	mode: ['client'],
 	test({ window, assert }) {
+		flushSync();
 		// In here to give effects etc time to execute
 		assert.htmlEqual(window.document.body.innerHTML, 'this should be executed');
 	}