diff --git a/packages/ui/src/components/session/SessionSidebar.tsx b/packages/ui/src/components/session/SessionSidebar.tsx
index 5a3c716c..4c875e8b 100644
--- a/packages/ui/src/components/session/SessionSidebar.tsx
+++ b/packages/ui/src/components/session/SessionSidebar.tsx
@@ -381,6 +381,11 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
     }));
   }, [globalActiveSessions, isVSCode, knownSessionDirectories, liveSessions]);
 
+  const persistenceSessions = React.useMemo(
+    () => [...globalActiveSessions, ...archivedSessions],
+    [archivedSessions, globalActiveSessions],
+  );
+
   const syncSessionStructureSignature = React.useMemo(
     () => liveSessions
       .map((session) => {
@@ -541,7 +546,7 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
       projectActiveSession: PROJECT_ACTIVE_SESSION_STORAGE_KEY,
       groupCollapse: GROUP_COLLAPSE_STORAGE_KEY,
     },
-    sessions,
+    sessions: persistenceSessions,
     pinnedSessionIds,
     setPinnedSessionIds,
     groupOrderByProject,
diff --git a/packages/ui/src/components/session/sidebar/hooks/pinnedSessionCleanup.ts b/packages/ui/src/components/session/sidebar/hooks/pinnedSessionCleanup.ts
new file mode 100644
index 00000000..f2381896
--- /dev/null
+++ b/packages/ui/src/components/session/sidebar/hooks/pinnedSessionCleanup.ts
@@ -0,0 +1,20 @@
+import type { Session } from '@opencode-ai/sdk/v2';
+
+export const prunePinnedSessionIds = (
+  sessions: Array<Pick<Session, 'id'>>,
+  pinnedSessionIds: Set<string>,
+): Set<string> => {
+  const existingSessionIds = new Set(sessions.map((session) => session.id));
+  let changed = false;
+  const next = new Set<string>();
+
+  pinnedSessionIds.forEach((id) => {
+    if (existingSessionIds.has(id)) {
+      next.add(id);
+      return;
+    }
+    changed = true;
+  });
+
+  return changed ? next : pinnedSessionIds;
+};
diff --git a/packages/ui/src/components/session/sidebar/hooks/useSidebarPersistence.test.ts b/packages/ui/src/components/session/sidebar/hooks/useSidebarPersistence.test.ts
new file mode 100644
index 00000000..2d0b8a29
--- /dev/null
+++ b/packages/ui/src/components/session/sidebar/hooks/useSidebarPersistence.test.ts
@@ -0,0 +1,26 @@
+import { describe, expect, test } from 'bun:test';
+import type { Session } from '@opencode-ai/sdk/v2';
+import { prunePinnedSessionIds } from './pinnedSessionCleanup';
+
+const makeSession = (id: string): Pick<Session, 'id'> => ({ id });
+
+describe('prunePinnedSessionIds', () => {
+  test('keeps pinned ids that still exist in the authoritative session list', () => {
+    const sessions = [makeSession('visible-session'), makeSession('hidden-session')];
+    const pinnedSessionIds = new Set(['hidden-session', 'missing-session']);
+
+    const next = prunePinnedSessionIds(sessions, pinnedSessionIds);
+
+    expect([...next]).toEqual(['hidden-session']);
+    expect(next).not.toBe(pinnedSessionIds);
+  });
+
+  test('returns the original set when nothing needs pruning', () => {
+    const sessions = [makeSession('visible-session'), makeSession('hidden-session')];
+    const pinnedSessionIds = new Set(['visible-session', 'hidden-session']);
+
+    const next = prunePinnedSessionIds(sessions, pinnedSessionIds);
+
+    expect(next).toBe(pinnedSessionIds);
+  });
+});
diff --git a/packages/ui/src/components/session/sidebar/hooks/useSidebarPersistence.ts b/packages/ui/src/components/session/sidebar/hooks/useSidebarPersistence.ts
index a6652533..13519d9a 100644
--- a/packages/ui/src/components/session/sidebar/hooks/useSidebarPersistence.ts
+++ b/packages/ui/src/components/session/sidebar/hooks/useSidebarPersistence.ts
@@ -2,6 +2,7 @@ import React from 'react';
 import type { Session } from '@opencode-ai/sdk/v2';
 import { updateDesktopSettings } from '@/lib/persistence';
 import { useProjectsStore } from '@/stores/useProjectsStore';
+import { prunePinnedSessionIds } from './pinnedSessionCleanup';
 
 type SafeStorageLike = {
   getItem: (key: string) => string | null;
@@ -154,22 +155,8 @@ export const useSidebarPersistence = (args: Args) => {
       return;
     }
 
-    if (sessions.length === 0) {
-      return;
-    }
-
-    const existingSessionIds = new Set(sessions.map((session) => session.id));
     setPinnedSessionIds((prev) => {
-      let changed = false;
-      const next = new Set<string>();
-      prev.forEach((id) => {
-        if (existingSessionIds.has(id)) {
-          next.add(id);
-        } else {
-          changed = true;
-        }
-      });
-      return changed ? next : prev;
+      return prunePinnedSessionIds(sessions, prev);
     });
   }, [hasLoadedGlobalSessions, sessions, setPinnedSessionIds]);