diff --git a/lib/shared-store/__tests__/import-admin.test.ts b/lib/shared-store/__tests__/import-admin.test.ts
new file mode 100644
index 000000000..92a55d347
--- /dev/null
+++ b/lib/shared-store/__tests__/import-admin.test.ts
@@ -0,0 +1,81 @@
+/**
+ * @vitest-environment node
+ */
+import { mkdirSync, mkdtempSync, readFileSync, rmSync, statSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import path from 'node:path';
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+
+// Moving a single-instance install to a shared store (#1066): the admin
+// config, password, state and audit log come along, a second run changes
+// nothing, and the local files stay as they were.
+
+import { steps } from '../import/admin';
+import { importLocalData } from '../import';
+import { getStore, setStoreForTests } from '../index';
+import { resetLocalStoreForTests } from '../local';
+import { separateFakeStore } from '@/lib/admin/__tests__/shared-store-fake';
+import { adminConfigDocs, adminStateDocs } from '@/lib/admin/admin-store';
+import { AUDIT_LOG_OPTIONS } from '@/lib/admin/audit';
+
+let dir: string;
+const config = (file: string) => path.join(dir, 'config', file);
+const state = (file: string) => path.join(dir, 'state', file);
+const LOCAL: Record<string, string> = {};
+
+beforeEach(() => {
+  dir = mkdtempSync(path.join(tmpdir(), 'bw-import-admin-'));
+  vi.stubEnv('ADMIN_CONFIG_DIR', path.join(dir, 'config'));
+  vi.stubEnv('ADMIN_STATE_DIR', path.join(dir, 'state'));
+  mkdirSync(path.join(dir, 'config'));
+  mkdirSync(path.join(dir, 'state'));
+  const files = {
+    [config('config.json')]: JSON.stringify({ appName: 'Imported', setupComplete: true }, null, 2),
+    [config('policy.json')]: JSON.stringify({ features: { calendarEnabled: false } }, null, 2),
+    [config('admin.json')]: JSON.stringify({ passwordHash: '$scrypt$N=16384,r=8,p=1$c2FsdA==$aGFzaA==' }, null, 2),
+    [config('.config-locked')]: '2026-10-31T12:00:00.000Z',
+    [state('admin-state.json')]: JSON.stringify({ createdAt: 'x', lastLogin: null, passwordChangedAt: 'x', sessionGeneration: 3 }, null, 2),
+    [state('audit.log')]: '{"ts":"1","action":"admin.login","detail":{},"ip":"1"}\n{"ts":"2","action":"admin.logout","detail":{},"ip":"1"}\n',
+  };
+  for (const [file, content] of Object.entries(files)) {
+    writeFileSync(file, content);
+    LOCAL[file] = content;
+  }
+  resetLocalStoreForTests();
+  setStoreForTests(separateFakeStore(path.join(dir, 'store')));
+});
+
+afterEach(() => {
+  setStoreForTests(null);
+  resetLocalStoreForTests();
+  vi.unstubAllEnvs();
+  rmSync(dir, { recursive: true, force: true });
+});
+
+describe('admin import', () => {
+  it('copies the admin files once and leaves them on disk', async () => {
+    const mtimes = Object.keys(LOCAL).map((file) => statSync(file).mtimeMs);
+
+    expect((await importLocalData(steps)).imported).toEqual({ 'admin-config': 4, 'admin-state': 1, audit: 2 });
+    for (const id of ['config.json', 'policy.json', 'admin.json', '.config-locked']) {
+      expect((await adminConfigDocs().get(id))!.data.toString('utf-8')).toBe(LOCAL[config(id)]);
+    }
+    expect((await adminStateDocs().get('admin-state.json'))!.data.toString('utf-8')).toBe(LOCAL[state('admin-state.json')]);
+    const log = await getStore().log('audit', AUDIT_LOG_OPTIONS).readAll();
+    expect(log.map((line) => JSON.parse(line).action)).toEqual(['admin.login', 'admin.logout']);
+
+    expect((await importLocalData(steps)).imported).toEqual({ 'admin-config': 0, 'admin-state': 0, audit: 0 });
+    expect(await getStore().log('audit', AUDIT_LOG_OPTIONS).length()).toBe(2);
+
+    Object.keys(LOCAL).forEach((file, i) => {
+      expect(readFileSync(file, 'utf-8')).toBe(LOCAL[file]);
+      expect(statSync(file).mtimeMs).toBe(mtimes[i]);
+    });
+  });
+
+  it('keeps what the store already holds', async () => {
+    await adminConfigDocs().put('config.json', '{"appName":"Already shared"}');
+    expect((await importLocalData(steps)).imported['admin-config']).toBe(3);
+    expect((await adminConfigDocs().get('config.json'))!.data.toString('utf-8')).toBe('{"appName":"Already shared"}');
+  });
+});
diff --git a/lib/shared-store/import/admin.ts b/lib/shared-store/import/admin.ts
new file mode 100644
index 000000000..366801882
--- /dev/null
+++ b/lib/shared-store/import/admin.ts
@@ -0,0 +1,54 @@
+import type { ImportStep } from '../import';
+import { getStore, type CollectionOptions } from '../index';
+import { localCollection, localLog } from '../local';
+import {
+  ADMIN_CONFIG_COLLECTION,
+  ADMIN_STATE_COLLECTION,
+  adminConfigOptions,
+  adminStateOptions,
+} from '@/lib/admin/admin-store';
+import { AUDIT_LOG_OPTIONS } from '@/lib/admin/audit';
+
+/**
+ * Part `admin` of the import (#1066): the admin config, the admin password
+ * and its state, and the audit log of a single-instance install. Reads the
+ * local files as local mode does and writes only what the shared store
+ * doesn't hold yet. With ADMIN_CONFIG_READONLY the config collection is the
+ * mounted files on every replica, so nothing of it is copied.
+ */
+
+async function copyDocs(name: string, options: CollectionOptions, ids: string[]): Promise<number> {
+  const local = localCollection(name, options);
+  const shared = getStore().collection(name, options);
+  let written = 0;
+  for (const id of ids) {
+    const doc = await local.get(id);
+    if (!doc) continue;
+    if ((await shared.put(id, doc.data, { ifVersion: null })).ok) written++;
+  }
+  return written;
+}
+
+export const steps: ImportStep[] = [
+  {
+    name: 'admin-config',
+    run: () => copyDocs(ADMIN_CONFIG_COLLECTION, adminConfigOptions, ['config.json', 'policy.json', 'admin.json', '.config-locked']),
+  },
+  {
+    name: 'admin-state',
+    run: () => copyDocs(ADMIN_STATE_COLLECTION, adminStateOptions, ['admin-state.json']),
+  },
+  {
+    // The current audit.log, as the dashboard shows it; the rotated files
+    // stay on disk. Only into an empty shared log, so a second run (or a
+    // replica that joins later) adds nothing twice.
+    name: 'audit',
+    run: async () => {
+      const shared = getStore().log('audit', AUDIT_LOG_OPTIONS);
+      if ((await shared.length()) > 0) return 0;
+      const lines = (await localLog('audit', AUDIT_LOG_OPTIONS).readAll()).slice(-AUDIT_LOG_OPTIONS.maxEntries);
+      for (const line of lines) await shared.append(line);
+      return lines.length;
+    },
+  },
+];