diff --git a/src/renderer/src/components/terminal/terminal-tab-actions-unrouted-close.test.ts b/src/renderer/src/components/terminal/terminal-tab-actions-unrouted-close.test.ts
new file mode 100644
index 00000000000..1c0b4b07801
--- /dev/null
+++ b/src/renderer/src/components/terminal/terminal-tab-actions-unrouted-close.test.ts
@@ -0,0 +1,85 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { toRemoteRuntimePtyId } from '../../../../shared/remote-runtime-pty-id'
+
+const { closeWebRuntimeSessionTabMock, getStateMock, isWebRuntimeSessionActiveMock } = vi.hoisted(
+  () => ({
+    closeWebRuntimeSessionTabMock: vi.fn(),
+    getStateMock: vi.fn(),
+    isWebRuntimeSessionActiveMock: vi.fn()
+  })
+)
+
+vi.mock('@/store', () => ({ useAppStore: { getState: getStateMock } }))
+
+vi.mock('@/runtime/web-runtime-session', () => ({
+  closeWebRuntimeSessionTab: closeWebRuntimeSessionTabMock,
+  isWebRuntimeSessionActive: isWebRuntimeSessionActiveMock,
+  toHostSessionTabId: (tabId: string) => tabId
+}))
+
+vi.mock('@/runtime/web-session-tabs-sync', () => ({
+  getLatestWebSessionTabsPublicationEpoch: () => null,
+  resolveHostSessionTabIdForWebSessionTab: () => null
+}))
+
+import { closeTerminalTab } from './terminal-tab-actions'
+
+const WORKTREE_ID = 'repo-1::/srv/app'
+
+/** The worktree catalog has not hydrated yet, so the worktree itself names no host (#11308). */
+function unhydratedState(ptyId: string | null, closeTab = vi.fn()) {
+  return {
+    settings: { activeRuntimeEnvironmentId: null },
+    repos: [],
+    worktreesByRepo: {},
+    detectedWorktreesByRepo: {},
+    tabsByWorktree: { [WORKTREE_ID]: [{ id: 'tab-1', ptyId, worktreeId: WORKTREE_ID }] },
+    unifiedTabsByWorktree: {},
+    ptyIdsByTabId: {},
+    terminalLayoutsByTabId: {},
+    lastKnownRelayPtyIdByTabId: {},
+    deferredSshSessionIdsByTabId: {},
+    pendingReconnectPtyIdByTabId: {},
+    activeWorktreeId: null,
+    activeTabId: null,
+    openFiles: [],
+    closeTab,
+    setActiveTab: vi.fn()
+  }
+}
+
+describe('closeTerminalTab before the worktree catalog names a host', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+  })
+
+  it('sends the close to the host its PTY id names', () => {
+    isWebRuntimeSessionActiveMock.mockImplementation((id: string | null) => id === 'env-1')
+    const closeTab = vi.fn()
+    getStateMock.mockReturnValue(unhydratedState(toRemoteRuntimePtyId('h-1', 'env-1'), closeTab))
+    const onCancel = vi.fn()
+
+    closeTerminalTab('tab-1', { onCancel })
+
+    expect(onCancel).not.toHaveBeenCalled()
+    expect(closeWebRuntimeSessionTabMock).toHaveBeenCalledWith({
+      worktreeId: WORKTREE_ID,
+      tabId: 'tab-1',
+      environmentId: 'env-1',
+      reason: 'user'
+    })
+  })
+
+  it('still closes the tab locally when nothing names its host', () => {
+    isWebRuntimeSessionActiveMock.mockReturnValue(false)
+    const closeTab = vi.fn()
+    getStateMock.mockReturnValue(unhydratedState(null, closeTab))
+    const onClosed = vi.fn()
+
+    closeTerminalTab('tab-1', { onClosed })
+
+    expect(closeTab).toHaveBeenCalledWith('tab-1')
+    expect(onClosed).toHaveBeenCalled()
+    expect(closeWebRuntimeSessionTabMock).not.toHaveBeenCalled()
+  })
+})
diff --git a/src/renderer/src/components/terminal/terminal-tab-actions.ts b/src/renderer/src/components/terminal/terminal-tab-actions.ts
index 3013b921f70..489bbf01178 100644
--- a/src/renderer/src/components/terminal/terminal-tab-actions.ts
+++ b/src/renderer/src/components/terminal/terminal-tab-actions.ts
@@ -8,7 +8,7 @@ import {
   getLatestWebSessionTabsPublicationEpoch,
   resolveHostSessionTabIdForWebSessionTab
 } from '@/runtime/web-session-tabs-sync'
-import { resolveTerminalWorktreeRoute } from '@/lib/terminal-worktree-route'
+import { resolveTerminalCloseRoute } from '@/lib/terminal-close-route'
 import {
   guardPinnedTabClose,
   isUnifiedTabPinned,
@@ -82,11 +82,9 @@ export function closeTerminalTab(
     return
   }
   const { worktreeId: owningWorktreeId, terminalTabId } = target
-  const worktreeRoute = resolveTerminalWorktreeRoute(state, owningWorktreeId)
-  if (!worktreeRoute) {
-    options?.onCancel?.()
-    return
-  }
+  // Why no early return: an unrouted close still prunes locally and reaches main's close record;
+  // teardown of a PTY whose host is unproven fails closed on its own.
+  const worktreeRoute = resolveTerminalCloseRoute(state, owningWorktreeId, terminalTabId)
 
   // Why: a pinned tab routes through the confirmation guard instead of closing
   // outright. `force` is the post-confirmation re-entry, which skips the guard.
@@ -130,7 +128,7 @@ export function closeTerminalTab(
     return
   }
 
-  const runtimeEnvironmentId = worktreeRoute.runtimeEnvironmentId
+  const runtimeEnvironmentId = worktreeRoute?.runtimeEnvironmentId ?? null
   if (runtimeEnvironmentId && isWebRuntimeSessionActive(runtimeEnvironmentId)) {
     if (options?.reason === 'pty-exit') {
       // Why: stream exit is not host-tab closure; the HUB snapshot decides whether reconnect restores or removes this tab.
diff --git a/src/renderer/src/lib/terminal-close-route.ts b/src/renderer/src/lib/terminal-close-route.ts
new file mode 100644
index 00000000000..0232951a823
--- /dev/null
+++ b/src/renderer/src/lib/terminal-close-route.ts
@@ -0,0 +1,45 @@
+import { parseExecutionHostId } from '../../../shared/execution-host'
+import { getPtyExecutionHost } from '../../../shared/terminal-execution-host'
+import type { AppState } from '@/store/types'
+import { collectPtyIdsForTab } from '@/store/slices/terminal-tab-retirement'
+import { resolveTerminalWorktreeRoute, type TerminalWorktreeRoute } from './terminal-worktree-route'
+
+function routeForHost(hostId: string | null | undefined): TerminalWorktreeRoute | null {
+  const host = parseExecutionHostId(hostId)
+  if (host?.kind === 'runtime') {
+    return { runtimeEnvironmentId: host.environmentId }
+  }
+  return host ? { runtimeEnvironmentId: null } : null
+}
+
+/**
+ * Which host a terminal tab's close goes to: the worktree catalog's route, else the one host the
+ * tab's own PTY ids name, else the host recorded on its unified tab. Null when nothing names one,
+ * e.g. before the catalog hydrates (#11308); per-PTY teardown still fails closed then.
+ */
+export function resolveTerminalCloseRoute(
+  state: AppState,
+  worktreeId: string,
+  terminalTabId: string
+): TerminalWorktreeRoute | null {
+  const catalogRoute = resolveTerminalWorktreeRoute(state, worktreeId)
+  if (catalogRoute) {
+    return catalogRoute
+  }
+  const row = state.tabsByWorktree?.[worktreeId]?.find((tab) => tab.id === terminalTabId)
+  const ptyHosts = new Set(
+    collectPtyIdsForTab(state, terminalTabId, row?.ptyId ?? null)
+      .map(getPtyExecutionHost)
+      .filter((host) => host !== null)
+  )
+  if (ptyHosts.size > 0) {
+    // Why: an id that names no host ('foreign') or two hosts proves only that it is not local.
+    const [host] = ptyHosts
+    return ptyHosts.size === 1 && host !== 'foreign' ? routeForHost(host) : null
+  }
+  const unified = state.unifiedTabsByWorktree?.[worktreeId]?.find(
+    (tab) =>
+      tab.contentType === 'terminal' && (tab.entityId === terminalTabId || tab.id === terminalTabId)
+  )
+  return routeForHost(unified?.executionHostId)
+}
diff --git a/src/renderer/src/store/slices/tabs-close-dangling-group.test.ts b/src/renderer/src/store/slices/tabs-close-dangling-group.test.ts
new file mode 100644
index 00000000000..626b090ffd7
--- /dev/null
+++ b/src/renderer/src/store/slices/tabs-close-dangling-group.test.ts
@@ -0,0 +1,36 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { createTabsSliceMockApi } from './tabs-slice-test-harness'
+import { createTestStore } from './store-test-helpers'
+
+vi.mock('sonner', () => ({ toast: { info: vi.fn(), success: vi.fn(), error: vi.fn() } }))
+
+createTabsSliceMockApi()
+
+const WT = 'repo1::/tmp/feature'
+
+describe('closeUnifiedTab with a missing group record (#11308)', () => {
+  let store: ReturnType<typeof createTestStore>
+
+  beforeEach(() => {
+    store = createTestStore()
+  })
+
+  it.each(['terminal', 'editor'] as const)('still removes a %s tab', (contentType) => {
+    const kept = store.getState().createUnifiedTab(WT, contentType, { id: `${contentType}-kept` })
+    const closing = store.getState().createUnifiedTab(WT, contentType, { id: `${contentType}-x` })
+    store.setState({ groupsByWorktree: { [WT]: [] } })
+
+    const result = store.getState().closeUnifiedTab(closing.id)
+
+    expect(result).toEqual({ closedTabId: closing.id, wasLastTab: false, worktreeId: WT })
+    expect(store.getState().unifiedTabsByWorktree[WT]?.map((tab) => tab.id)).toEqual([kept.id])
+  })
+
+  it('reports the last tab when the worktree has no other tab', () => {
+    const only = store.getState().createUnifiedTab(WT, 'editor', { id: 'editor-only' })
+    store.setState({ groupsByWorktree: { [WT]: [] } })
+
+    expect(store.getState().closeUnifiedTab(only.id)?.wasLastTab).toBe(true)
+    expect(store.getState().unifiedTabsByWorktree[WT]).toEqual([])
+  })
+})
diff --git a/src/renderer/src/store/slices/tabs/tabs-close-actions.ts b/src/renderer/src/store/slices/tabs/tabs-close-actions.ts
index 6af491e7a37..56ed2fb6623 100644
--- a/src/renderer/src/store/slices/tabs/tabs-close-actions.ts
+++ b/src/renderer/src/store/slices/tabs/tabs-close-actions.ts
@@ -34,12 +34,12 @@ export function createTabsCloseActions(
       }
       const { tab, worktreeId } = found
       const group = findGroupForTab(state.groupsByWorktree, worktreeId, tab.groupId)
-      if (!group) {
-        return null
-      }
+      // Why: a tab whose group record vanished must still close; its order is the worktree's tabs.
+      const groupOrder =
+        group?.tabOrder ?? (state.unifiedTabsByWorktree[worktreeId] ?? []).map((item) => item.id)
 
       if (tab.contentType === 'terminal' && !opts?.terminalRetirementHandled) {
-        const dedupedGroupOrder = dedupeTabOrder(group.tabOrder)
+        const dedupedGroupOrder = dedupeTabOrder(groupOrder)
         const wasLastTab =
           dedupeTabOrder(dedupedGroupOrder.filter((id) => id !== tabId)).length === 0
         // Why: unified-only hydrated tabs still own provider sessions without a legacy row, so retire every terminal close by entity id.
@@ -47,7 +47,7 @@ export function createTabsCloseActions(
         return { closedTabId: tabId, wasLastTab, worktreeId }
       }
 
-      const dedupedGroupOrder = dedupeTabOrder(group.tabOrder)
+      const dedupedGroupOrder = dedupeTabOrder(groupOrder)
       const remainingOrder = dedupeTabOrder(dedupedGroupOrder.filter((id) => id !== tabId))
       const wasLastTab = remainingOrder.length === 0
       if (tab.contentType === 'agent-session') {
@@ -78,13 +78,13 @@ export function createTabsCloseActions(
       }
       // Why: on closing the active tab, walk the MRU stack to the previously-active tab; pickNextActiveTab falls back to the neighbor.
       const nextActiveTabId =
-        group.activeTabId === tabId
+        group?.activeTabId === tabId
           ? wasLastTab
             ? null
             : pickNextActiveTab(dedupedGroupOrder, group.recentTabIds, tabId)
-          : group.activeTabId
+          : (group?.activeTabId ?? null)
       const nextRecentTabIds = sanitizeRecentTabIds(
-        (group.recentTabIds ?? []).filter((id) => id !== tabId),
+        (group?.recentTabIds ?? []).filter((id) => id !== tabId),
         remainingOrder
       )
       const terminalEntityId = tab.contentType === 'terminal' ? tab.entityId : null
@@ -100,7 +100,7 @@ export function createTabsCloseActions(
           delete nextUnreadTerminalTabs[terminalEntityId]
         }
         let nextGroups = (current.groupsByWorktree[worktreeId] ?? []).map((candidate) =>
-          candidate.id === group.id
+          candidate.id === group?.id
             ? {
                 ...candidate,
                 activeTabId: nextActiveTabId,
@@ -111,7 +111,7 @@ export function createTabsCloseActions(
         )
         let nextLayoutByWorktree = current.layoutByWorktree
         let nextActiveGroupIdByWorktree = current.activeGroupIdByWorktree
-        if (wasLastTab && current.layoutByWorktree[worktreeId] && nextGroups.length > 1) {
+        if (group && wasLastTab && current.layoutByWorktree[worktreeId] && nextGroups.length > 1) {
           nextGroups = nextGroups.filter((candidate) => candidate.id !== group.id)
           const collapsedState = collapseGroupLayout(
             current.layoutByWorktree,
diff --git a/src/renderer/src/store/slices/terminal-tab-retirement.ts b/src/renderer/src/store/slices/terminal-tab-retirement.ts
index 0276541b7da..0310c65ba7d 100644
--- a/src/renderer/src/store/slices/terminal-tab-retirement.ts
+++ b/src/renderer/src/store/slices/terminal-tab-retirement.ts
@@ -63,7 +63,7 @@ export function getTerminalPtyOwnershipIdentity(
   return JSON.stringify(['runtime', environmentId, remote.handle])
 }
 
-function collectPtyIdsForTab(
+export function collectPtyIdsForTab(
   state: TerminalTabRetirementState,
   tabId: string,
   rowPtyId: string | null | undefined