diff --git a/packages/kill-switch-client/src/index.test.ts b/packages/kill-switch-client/src/index.test.ts
index 7ac17a3e..c39084f3 100644
--- a/packages/kill-switch-client/src/index.test.ts
+++ b/packages/kill-switch-client/src/index.test.ts
@@ -79,7 +79,7 @@ describe('createKillSwitchClient', () => {
     await ks.check();
 
     expect(fetchMock).toHaveBeenCalledWith(
-      expect.stringContaining('/flags/kill-switch'),
+      expect.stringContaining('/settings/kill-switch'),
       expect.objectContaining({
         headers: expect.objectContaining({ 'x-product-id': 'testapp' }),
       })
diff --git a/packages/kill-switch-client/src/index.ts b/packages/kill-switch-client/src/index.ts
index e41339d5..de7bafab 100644
--- a/packages/kill-switch-client/src/index.ts
+++ b/packages/kill-switch-client/src/index.ts
@@ -1,7 +1,7 @@
 /**
  * Browser/React Native-safe kill switch client for platform-service.
  *
- * Checks GET /api/flags/kill-switch to determine if the app is disabled.
+ * Checks GET /api/settings/kill-switch to determine if the app is disabled.
  * Fail-open: returns { disabled: false } on any network error.
  *
  * @example
@@ -49,8 +49,15 @@ export function createKillSwitchClient(config: KillSwitchClientConfig): KillSwit
           ? globalThis.crypto.randomUUID()
           : `${Date.now()}-${Math.random().toString(36).slice(2, 10)}`;
 
+      // Endpoint lives under /settings/kill-switch in platform-service's
+      // settings module (no auth required). The route reads the
+      // `kill_switch` feature flag from the flags container and returns
+      // { enabled, disabled, message }. Older versions of this client
+      // pointed at /flags/kill-switch which does not exist; that bug
+      // was masked by fail-open behavior on 404 but produced noisy
+      // 404s on every page load.
       const res = await globalThis.fetch(
-        `${baseUrl}/flags/kill-switch?platform=${encodeURIComponent(platform)}`,
+        `${baseUrl}/settings/kill-switch?platform=${encodeURIComponent(platform)}&productId=${encodeURIComponent(productId)}`,
         {
           headers: { 'x-product-id': productId, 'x-request-id': requestId },
         }