diff --git a/.changeset/quick-meals-shout.md b/.changeset/quick-meals-shout.md
new file mode 100644
index 0000000000..21871edd67
--- /dev/null
+++ b/.changeset/quick-meals-shout.md
@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: don't notify `searchParams` subscribers when the URL changes without affecting the search string
diff --git a/packages/svelte/src/reactivity/url-search-params.js b/packages/svelte/src/reactivity/url-search-params.js
index 38cf3ebe4f..d745bb6b08 100644
--- a/packages/svelte/src/reactivity/url-search-params.js
+++ b/packages/svelte/src/reactivity/url-search-params.js
@@ -54,6 +54,11 @@ export class SvelteURLSearchParams extends URLSearchParams {
 	 */
 	[REPLACE](params) {
 		if (this.#updating) return;
+
+		// the URL may have changed in a way that leaves the search string untouched —
+		// don't rebuild the params or notify readers if nothing changed
+		if (params.toString() === super.toString()) return;
+
 		this.#updating = true;
 
 		for (const key of [...super.keys()]) {
@@ -126,6 +131,16 @@ export class SvelteURLSearchParams extends URLSearchParams {
 		return super.keys();
 	}
 
+	/**
+	 * @param {(value: string, key: string, parent: URLSearchParams) => void} callback
+	 * @param {any} [this_arg]
+	 * @returns {void}
+	 */
+	forEach(callback, this_arg) {
+		get(this.#version);
+		super.forEach(callback, this_arg);
+	}
+
 	/**
 	 * @param {string} name
 	 * @param {string} value
diff --git a/packages/svelte/src/reactivity/url-search-params.test.ts b/packages/svelte/src/reactivity/url-search-params.test.ts
index b0c84872b0..765b4020f3 100644
--- a/packages/svelte/src/reactivity/url-search-params.test.ts
+++ b/packages/svelte/src/reactivity/url-search-params.test.ts
@@ -244,3 +244,24 @@ test('URLSearchParams.toString', () => {
 test('SvelteURLSearchParams instanceof URLSearchParams', () => {
 	assert.ok(new SvelteURLSearchParams() instanceof URLSearchParams);
 });
+
+test('params.forEach is reactive', () => {
+	const params = new SvelteURLSearchParams('foo=1');
+	const log: any = [];
+
+	const cleanup = effect_root(() => {
+		render_effect(() => {
+			const entries: string[] = [];
+			params.forEach((value, key) => entries.push(`${key}=${value}`));
+			log.push(entries.join('&'));
+		});
+	});
+
+	flushSync(() => {
+		params.set('foo', '2');
+	});
+
+	assert.deepEqual(log, ['foo=1', 'foo=2']);
+
+	cleanup();
+});
diff --git a/packages/svelte/src/reactivity/url.test.ts b/packages/svelte/src/reactivity/url.test.ts
index a79aa32315..d698116421 100644
--- a/packages/svelte/src/reactivity/url.test.ts
+++ b/packages/svelte/src/reactivity/url.test.ts
@@ -166,3 +166,77 @@ test('url.search normalizes value', () => {
 test('SvelteURL instanceof URL', () => {
 	assert.ok(new SvelteURL('https://svelte.dev') instanceof URL);
 });
+
+test('url.searchParams subscribers are not notified by changes that leave the search string untouched', () => {
+	const url = new SvelteURL('https://svelte.dev/a?foo=bar');
+	const log: any = [];
+
+	const cleanup = effect_root(() => {
+		render_effect(() => {
+			log.push(url.searchParams.toString());
+		});
+	});
+
+	flushSync(() => {
+		// does not affect the search string
+		url.pathname = '/b';
+	});
+
+	flushSync(() => {
+		// neither does this
+		url.href = 'https://svelte.dev/c?foo=bar#hash';
+	});
+
+	flushSync(() => {
+		// but this does
+		url.search = '?foo=baz';
+	});
+
+	assert.deepEqual(log, ['foo=bar', 'foo=baz']);
+
+	cleanup();
+});
+
+test('url.searchParams.size is not notified by unrelated href changes', () => {
+	const url = new SvelteURL('https://svelte.dev/?foo=bar');
+	const log: any = [];
+
+	const cleanup = effect_root(() => {
+		render_effect(() => {
+			log.push(url.searchParams.size);
+		});
+	});
+
+	flushSync(() => {
+		url.href = 'https://svelte.dev/other?foo=bar';
+	});
+
+	flushSync(() => {
+		url.searchParams.append('baz', 'qux');
+	});
+
+	assert.deepEqual(log, [1, 2]);
+
+	cleanup();
+});
+
+test('url.searchParams.forEach re-runs when the search string changes via the URL', () => {
+	const url = new SvelteURL('https://svelte.dev/?foo=1');
+	const log: any = [];
+
+	const cleanup = effect_root(() => {
+		render_effect(() => {
+			const entries: string[] = [];
+			url.searchParams.forEach((value, key) => entries.push(`${key}=${value}`));
+			log.push(entries.join('&'));
+		});
+	});
+
+	flushSync(() => {
+		url.href = 'https://svelte.dev/?bar=2';
+	});
+
+	assert.deepEqual(log, ['foo=1', 'bar=2']);
+
+	cleanup();
+});