diff --git a/CHANGELOG.md b/CHANGELOG.md
index 418f190f..7f48fb87 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ and this project adheres to
 ### Fixed
 
 - 📈(frontend) downgrade unreachable external home URL from error to event
+- 🐛(frontend) handle 401 responses when syncing user preferences
 
 ## [1.26.0] - 2026-08-12
 
diff --git a/src/frontend/src/features/auth/api/useSyncUserPreferencesWithBackend.tsx b/src/frontend/src/features/auth/api/useSyncUserPreferencesWithBackend.tsx
index ed06e816..9e689585 100644
--- a/src/frontend/src/features/auth/api/useSyncUserPreferencesWithBackend.tsx
+++ b/src/frontend/src/features/auth/api/useSyncUserPreferencesWithBackend.tsx
@@ -6,6 +6,8 @@ import { queryClient } from '@/api/queryClient'
 import { updateUserPreferences } from './updateUserPreferences'
 import { convertToBackendLanguage } from '@/utils/languages'
 import { useUser } from './useUser'
+import { ApiError } from '@/api/ApiError.ts'
+import { reportError } from '@/features/analytics/telemetry'
 
 /**
  * Hook that synchronizes user browser preferences (language, timezone) with backend user settings.
@@ -42,6 +44,11 @@ export const useSyncUserPreferencesWithBackend = () => {
       }
     }
 
-    syncBrowserPreferencesToBackend()
+    syncBrowserPreferencesToBackend().catch((error) => {
+      if (error instanceof ApiError && error.statusCode === 401) return
+      reportError('generic_failure', error, {
+        context: '[useSyncUserPreferencesWithBackend] Failed to sync:',
+      })
+    })
   }, [i18n.language, isLoggedIn, user, mutateAsync])
 }