diff --git a/packages/client/src/components/layout/AppSidebar.vue b/packages/client/src/components/layout/AppSidebar.vue
index 48aafaf..041e72f 100644
--- a/packages/client/src/components/layout/AppSidebar.vue
+++ b/packages/client/src/components/layout/AppSidebar.vue
@@ -43,6 +43,10 @@ async function handleUpdate() {
   }
 }
 
+function handleReloadClient() {
+  appStore.reloadClient();
+}
+
 function handleLogout() {
   localStorage.clear();
   router.replace({ name: 'login' });
@@ -296,6 +300,9 @@ function openChangelog() {
         <span class="version-text" @click="openChangelog">Web UI v{{ appStore.serverVersion || "0.1.0" }}</span>
         <ThemeSwitch />
       </div>
+      <NButton v-if="appStore.clientOutdated" type="warning" size="tiny" block class="update-btn" @click="handleReloadClient">
+        {{ t('sidebar.reloadClientVersion', { version: appStore.serverVersion }) }}
+      </NButton>
       <NButton v-if="appStore.updateAvailable" type="primary" size="tiny" block class="update-btn" :loading="appStore.updating" @click="handleUpdate">
         {{ appStore.updating ? t('sidebar.updating') : t('sidebar.updateVersion', { version: appStore.latestVersion }) }}
       </NButton>
diff --git a/packages/client/src/i18n/locales/de.ts b/packages/client/src/i18n/locales/de.ts
index a4ad438..779993d 100644
--- a/packages/client/src/i18n/locales/de.ts
+++ b/packages/client/src/i18n/locales/de.ts
@@ -89,6 +89,7 @@ export default {
     disconnected: 'Getrennt',
     updateTip: 'Fuhren Sie "hermes-web-ui update" im Terminal aus, um zu aktualisieren',
     updateVersion: 'Aktualisieren auf v{version}',
+    reloadClientVersion: 'Für v{version} neu laden',
     updating: 'Aktualisierung...',
     updateSuccess: 'Aktualisierung abgeschlossen, bitte Server neu starten',
     updateFailed: 'Aktualisierung fehlgeschlagen',
diff --git a/packages/client/src/i18n/locales/en.ts b/packages/client/src/i18n/locales/en.ts
index 67b26e8..cf59dee 100644
--- a/packages/client/src/i18n/locales/en.ts
+++ b/packages/client/src/i18n/locales/en.ts
@@ -101,6 +101,7 @@ export default {
     expand: 'Expand menu',
     updateTip: 'Run "hermes-web-ui update" in terminal to update',
     updateVersion: 'Upgrade to v{version}',
+    reloadClientVersion: 'Reload for v{version}',
     updating: 'Updating...',
     updateSuccess: 'Update complete, please restart the server',
     updateFailed: 'Update failed',
diff --git a/packages/client/src/i18n/locales/es.ts b/packages/client/src/i18n/locales/es.ts
index e62011b..801d2db 100644
--- a/packages/client/src/i18n/locales/es.ts
+++ b/packages/client/src/i18n/locales/es.ts
@@ -89,6 +89,7 @@ export default {
     disconnected: 'Desconectado',
     updateTip: 'Ejecuta "hermes-web-ui update" en la terminal para actualizar',
     updateVersion: 'Actualizar a v{version}',
+    reloadClientVersion: 'Recargar para v{version}',
     updating: 'Actualizando...',
     updateSuccess: 'Actualizacion completa, por favor reinicia el servidor',
     updateFailed: 'Error al actualizar',
diff --git a/packages/client/src/i18n/locales/fr.ts b/packages/client/src/i18n/locales/fr.ts
index 2c5927b..be9c571 100644
--- a/packages/client/src/i18n/locales/fr.ts
+++ b/packages/client/src/i18n/locales/fr.ts
@@ -89,6 +89,7 @@ export default {
     disconnected: 'Deconnecte',
     updateTip: 'Executez "hermes-web-ui update" dans le terminal pour mettre a jour',
     updateVersion: 'Mettre a jour vers v{version}',
+    reloadClientVersion: 'Recharger pour v{version}',
     updating: 'Mise a jour...',
     updateSuccess: 'Mise a jour terminee, veuillez redemarrer le serveur',
     updateFailed: 'Echec de la mise a jour',
diff --git a/packages/client/src/i18n/locales/ja.ts b/packages/client/src/i18n/locales/ja.ts
index 92f8bd8..0f85513 100644
--- a/packages/client/src/i18n/locales/ja.ts
+++ b/packages/client/src/i18n/locales/ja.ts
@@ -89,6 +89,7 @@ export default {
     disconnected: '未接続',
     updateTip: 'ターミナルで "hermes-web-ui update" を実行して更新してください',
     updateVersion: 'v{version} にアップグレード',
+    reloadClientVersion: 'v{version} に再読み込み',
     updating: '更新中...',
     updateSuccess: '更新が完了しました。サーバーを再起動してください',
     updateFailed: '更新に失敗しました',
diff --git a/packages/client/src/i18n/locales/ko.ts b/packages/client/src/i18n/locales/ko.ts
index e891823..613f58e 100644
--- a/packages/client/src/i18n/locales/ko.ts
+++ b/packages/client/src/i18n/locales/ko.ts
@@ -89,6 +89,7 @@ export default {
     disconnected: '연결 끊김',
     updateTip: '터미널에서 "hermes-web-ui update"를 실행하여 업데이트하세요',
     updateVersion: 'v{version}(으)로 업그레이드',
+    reloadClientVersion: 'v{version}(으)로 새로고침',
     updating: '업데이트 중...',
     updateSuccess: '업데이트 완료, 서버를 재시작해 주세요',
     updateFailed: '업데이트 실패',
diff --git a/packages/client/src/i18n/locales/pt.ts b/packages/client/src/i18n/locales/pt.ts
index 4e32d7a..e53c502 100644
--- a/packages/client/src/i18n/locales/pt.ts
+++ b/packages/client/src/i18n/locales/pt.ts
@@ -89,6 +89,7 @@ export default {
     disconnected: 'Desconectado',
     updateTip: 'Execute "hermes-web-ui update" no terminal para atualizar',
     updateVersion: 'Atualizar para v{version}',
+    reloadClientVersion: 'Recarregar para v{version}',
     updating: 'Atualizando...',
     updateSuccess: 'Atualizacao concluida, por favor reinicie o servidor',
     updateFailed: 'Falha na atualizacao',
diff --git a/packages/client/src/i18n/locales/zh-TW.ts b/packages/client/src/i18n/locales/zh-TW.ts
index d5c48f4..08af624 100644
--- a/packages/client/src/i18n/locales/zh-TW.ts
+++ b/packages/client/src/i18n/locales/zh-TW.ts
@@ -101,6 +101,7 @@ export default {
     expand: '展開選單',
     updateTip: '在終端機執行 "hermes-web-ui update" 即可更新',
     updateVersion: '升級版本 v{version}',
+    reloadClientVersion: '重新整理到 v{version}',
     updating: '正在更新...',
     updateSuccess: '更新完成，請重新啟動服務',
     updateFailed: '更新失敗',
diff --git a/packages/client/src/i18n/locales/zh.ts b/packages/client/src/i18n/locales/zh.ts
index 4c32bf7..a992ef5 100644
--- a/packages/client/src/i18n/locales/zh.ts
+++ b/packages/client/src/i18n/locales/zh.ts
@@ -101,6 +101,7 @@ export default {
     expand: '展开菜单',
     updateTip: '在终端运行 "hermes-web-ui update" 即可更新',
     updateVersion: '升级版本 v{version}',
+    reloadClientVersion: '刷新到 v{version}',
     updating: '正在更新...',
     updateSuccess: '更新完成，请重启服务',
     updateFailed: '更新失败',
diff --git a/packages/client/src/stores/hermes/app.ts b/packages/client/src/stores/hermes/app.ts
index 38c3395..a4bd511 100644
--- a/packages/client/src/stores/hermes/app.ts
+++ b/packages/client/src/stores/hermes/app.ts
@@ -26,6 +26,7 @@ export const useAppStore = defineStore('app', () => {
   const serverVersion = ref(WEB_UI_VERSION)
   const latestVersion = ref('')
   const updateAvailable = ref(false)
+  const clientOutdated = ref(false)
   const updating = ref(false)
   const modelGroups = ref<AvailableModelGroup[]>([])
   const selectedModel = ref('')
@@ -63,11 +64,13 @@ export const useAppStore = defineStore('app', () => {
       const res = await checkHealth()
       connected.value = res.status === 'ok'
       if (res.webui_version) serverVersion.value = res.webui_version
+      clientOutdated.value = !!res.webui_version && res.webui_version !== WEB_UI_VERSION
       if (res.webui_latest) latestVersion.value = res.webui_latest
       updateAvailable.value = !!res.webui_update_available
       if (res.node_version) nodeVersion.value = res.node_version
     } catch {
       connected.value = false
+      clientOutdated.value = false
     }
   }
 
@@ -231,6 +234,12 @@ export const useAppStore = defineStore('app', () => {
     }
   }
 
+  function reloadClient() {
+    const url = new URL(window.location.href)
+    url.searchParams.set('__hwui_reload', Date.now().toString())
+    window.location.replace(url.toString())
+  }
+
   function toggleSidebar() {
     sidebarOpen.value = !sidebarOpen.value
   }
@@ -259,8 +268,10 @@ export const useAppStore = defineStore('app', () => {
     latestVersion,
     nodeVersion,
     updateAvailable,
+    clientOutdated,
     updating,
     doUpdate,
+    reloadClient,
     modelGroups,
     customModels,
     modelAliases,
diff --git a/tests/client/app-store.test.ts b/tests/client/app-store.test.ts
index fc43f9f..0dcd78a 100644
--- a/tests/client/app-store.test.ts
+++ b/tests/client/app-store.test.ts
@@ -152,6 +152,38 @@ describe('App Store', () => {
     expect(mockSystemApi.updateDefaultModel).not.toHaveBeenCalled()
   })
 
+  it('marks the client stale when the served Web UI version changes', async () => {
+    mockSystemApi.checkHealth.mockResolvedValue({
+      status: 'ok',
+      webui_version: '0.5.17',
+      webui_latest: '0.5.17',
+      webui_update_available: false,
+    })
+    const store = useAppStore()
+
+    await store.checkConnection()
+
+    expect(store.connected).toBe(true)
+    expect(store.serverVersion).toBe('0.5.17')
+    expect(store.clientOutdated).toBe(true)
+    expect(store.updateAvailable).toBe(false)
+  })
+
+  it('does not mark the client stale when the served Web UI version matches this bundle', async () => {
+    mockSystemApi.checkHealth.mockResolvedValue({
+      status: 'ok',
+      webui_version: 'test',
+      webui_latest: 'test',
+      webui_update_available: false,
+    })
+    const store = useAppStore()
+
+    await store.checkConnection()
+
+    expect(store.serverVersion).toBe('test')
+    expect(store.clientOutdated).toBe(false)
+  })
+
   it('clears the updating state and reports failure when self-update request fails', async () => {
     const consoleError = vi.spyOn(console, 'error').mockImplementation(() => {})
     mockSystemApi.triggerUpdate.mockRejectedValue(new Error('install failed'))
diff --git a/tests/client/sidebar-search.test.ts b/tests/client/sidebar-search.test.ts
index 0e3a55e..6a12fe1 100644
--- a/tests/client/sidebar-search.test.ts
+++ b/tests/client/sidebar-search.test.ts
@@ -3,6 +3,21 @@ import { beforeEach, describe, expect, it, vi } from 'vitest'
 import { mount } from '@vue/test-utils'
 
 const openSessionSearchMock = vi.hoisted(() => vi.fn())
+const mockAppStore = vi.hoisted(() => ({
+  sidebarOpen: true,
+  sidebarCollapsed: false,
+  connected: true,
+  serverVersion: 'test',
+  latestVersion: '',
+  updateAvailable: false,
+  clientOutdated: false,
+  updating: false,
+  toggleSidebar: vi.fn(),
+  toggleSidebarCollapsed: vi.fn(),
+  closeSidebar: vi.fn(),
+  doUpdate: vi.fn(),
+  reloadClient: vi.fn(),
+}))
 
 vi.mock('@/composables/useSessionSearch', () => ({
   useSessionSearch: () => ({
@@ -11,16 +26,7 @@ vi.mock('@/composables/useSessionSearch', () => ({
 }))
 
 vi.mock('@/stores/hermes/app', () => ({
-  useAppStore: () => ({
-    sidebarOpen: true,
-    connected: true,
-    serverVersion: 'test',
-    updateAvailable: false,
-    updating: false,
-    toggleSidebar: vi.fn(),
-    closeSidebar: vi.fn(),
-    doUpdate: vi.fn(),
-  }),
+  useAppStore: () => mockAppStore,
 }))
 
 vi.mock('vue-router', async (importOriginal) => {
@@ -55,7 +61,7 @@ vi.mock('naive-ui', async () => {
       error: vi.fn(),
     }),
     NButton: {
-      template: '<button><slot /></button>',
+      template: '<button v-bind="$attrs"><slot /></button>',
     },
     NSelect: {
       template: '<div />',
@@ -68,6 +74,12 @@ import AppSidebar from '@/components/layout/AppSidebar.vue'
 describe('AppSidebar search entry', () => {
   beforeEach(() => {
     openSessionSearchMock.mockClear()
+    mockAppStore.serverVersion = 'test'
+    mockAppStore.latestVersion = ''
+    mockAppStore.updateAvailable = false
+    mockAppStore.clientOutdated = false
+    mockAppStore.updating = false
+    mockAppStore.reloadClient.mockClear()
   })
 
   it('opens the session search modal from the sidebar button', async () => {
@@ -90,4 +102,26 @@ describe('AppSidebar search entry', () => {
     await searchButton!.trigger('click')
     expect(openSessionSearchMock).toHaveBeenCalledTimes(1)
   })
+
+  it('offers a client reload when the server version differs from the loaded bundle', async () => {
+    mockAppStore.clientOutdated = true
+    mockAppStore.serverVersion = '0.5.17'
+    const wrapper = mount(AppSidebar, {
+      global: {
+        stubs: {
+          ProfileSelector: true,
+          ModelSelector: true,
+          LanguageSwitch: true,
+          ThemeSwitch: true,
+        },
+      },
+    })
+
+    const reloadButton = wrapper.findAll('button')
+      .find(node => node.text().includes('sidebar.reloadClientVersion'))
+    expect(reloadButton).toBeTruthy()
+
+    await reloadButton!.trigger('click')
+    expect(mockAppStore.reloadClient).toHaveBeenCalledTimes(1)
+  })
 })