diff --git a/.changeset/smooth-poems-tap.md b/.changeset/smooth-poems-tap.md
new file mode 100644
index 0000000000..ac160656cf
--- /dev/null
+++ b/.changeset/smooth-poems-tap.md
@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: re-run fallback props if dependencies update
diff --git a/packages/svelte/src/internal/client/reactivity/props.js b/packages/svelte/src/internal/client/reactivity/props.js
index e208d3b6f6..5626639a84 100644
--- a/packages/svelte/src/internal/client/reactivity/props.js
+++ b/packages/svelte/src/internal/client/reactivity/props.js
@@ -1,4 +1,4 @@
-/** @import { Effect, Source } from './types.js' */
+/** @import { Derived, Effect, Source } from './types.js' */
 import { DEV } from 'esm-env';
 import {
 	PROPS_IS_BINDABLE,
@@ -283,8 +283,14 @@ export function prop(props, key, flags, fallback) {
 
 	var fallback_value = /** @type {V} */ (fallback);
 	var fallback_dirty = true;
+	var fallback_signal = /** @type {Derived<V> | undefined} */ (undefined);
 
 	var get_fallback = () => {
+		if (lazy && runes) {
+			fallback_signal ??= derived(/** @type {() => V} */ (fallback));
+			return get(fallback_signal);
+		}
+
 		if (fallback_dirty) {
 			fallback_dirty = false;
 
diff --git a/packages/svelte/tests/runtime-runes/samples/props-default-value-lazy-accessors/main.svelte b/packages/svelte/tests/runtime-runes/samples/props-default-value-lazy-accessors/main.svelte
index fe2ac37bd3..f6437d6589 100644
--- a/packages/svelte/tests/runtime-runes/samples/props-default-value-lazy-accessors/main.svelte
+++ b/packages/svelte/tests/runtime-runes/samples/props-default-value-lazy-accessors/main.svelte
@@ -1,5 +1,5 @@
 <script>
-	let log = $state([]);
+	let log = [];
 
 	const fallback_value = 1;
 	const nested = {
diff --git a/packages/svelte/tests/runtime-runes/samples/props-default-value-lazy/sub.svelte b/packages/svelte/tests/runtime-runes/samples/props-default-value-lazy/sub.svelte
index fe2ac37bd3..f6437d6589 100644
--- a/packages/svelte/tests/runtime-runes/samples/props-default-value-lazy/sub.svelte
+++ b/packages/svelte/tests/runtime-runes/samples/props-default-value-lazy/sub.svelte
@@ -1,5 +1,5 @@
 <script>
-	let log = $state([]);
+	let log = [];
 
 	const fallback_value = 1;
 	const nested = {
diff --git a/packages/svelte/tests/runtime-runes/samples/props-default-value-reactivity/_config.js b/packages/svelte/tests/runtime-runes/samples/props-default-value-reactivity/_config.js
new file mode 100644
index 0000000000..b3274d02ec
--- /dev/null
+++ b/packages/svelte/tests/runtime-runes/samples/props-default-value-reactivity/_config.js
@@ -0,0 +1,19 @@
+import { flushSync, tick } from 'svelte';
+import { test } from '../../test';
+
+export default test({
+	accessors: false,
+	test({ assert, target }) {
+		const btn = target.querySelector('button');
+
+		btn?.click();
+		flushSync();
+		assert.htmlEqual(
+			target.innerHTML,
+			`
+			<p>greeting: Hola</p>
+			<button>Change Language</button>
+			`
+		);
+	}
+});
diff --git a/packages/svelte/tests/runtime-runes/samples/props-default-value-reactivity/main.svelte b/packages/svelte/tests/runtime-runes/samples/props-default-value-reactivity/main.svelte
new file mode 100644
index 0000000000..c26c4ca75a
--- /dev/null
+++ b/packages/svelte/tests/runtime-runes/samples/props-default-value-reactivity/main.svelte
@@ -0,0 +1,10 @@
+<script>
+	import Sub from './sub.svelte';
+	import { set_translation } from './translations.svelte.js';
+</script>
+
+<Sub />
+
+<button onclick={() => set_translation('Hola')}>
+	Change Language
+</button>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-runes/samples/props-default-value-reactivity/sub.svelte b/packages/svelte/tests/runtime-runes/samples/props-default-value-reactivity/sub.svelte
new file mode 100644
index 0000000000..b3cd3fae36
--- /dev/null
+++ b/packages/svelte/tests/runtime-runes/samples/props-default-value-reactivity/sub.svelte
@@ -0,0 +1,9 @@
+<script>
+	import { get_translation } from './translations.svelte.js';
+
+	const {
+		p0 = get_translation()
+	} = $props();
+</script>
+
+<p>greeting: {p0}</p>
\ No newline at end of file
diff --git a/packages/svelte/tests/runtime-runes/samples/props-default-value-reactivity/translations.svelte.js b/packages/svelte/tests/runtime-runes/samples/props-default-value-reactivity/translations.svelte.js
new file mode 100644
index 0000000000..4aa4dc9999
--- /dev/null
+++ b/packages/svelte/tests/runtime-runes/samples/props-default-value-reactivity/translations.svelte.js
@@ -0,0 +1,9 @@
+let greeting = $state('Hello');
+
+export function get_translation() {
+	return greeting;
+}
+
+export function set_translation(value) {
+	greeting = value;
+}