diff --git a/.changeset/fix-create-stale-data-retry.md b/.changeset/fix-create-stale-data-retry.md
new file mode 100644
index 000000000..454df6128
--- /dev/null
+++ b/.changeset/fix-create-stale-data-retry.md
@@ -0,0 +1,5 @@
+---
+'@keystatic/core': patch
+---
+
+Fix creating an entry always failing with "This entry has been updated since it was opened" when an unrelated commit landed on the branch after the admin UI was loaded. Creating an entry now retries on the new branch head when the entry still doesn't exist there, matching the existing behaviour for edits. If an entry with the same slug was created in the meantime, the "create a new branch" dialog is still shown.
diff --git a/packages/keystatic/src/app/updating.test.tsx b/packages/keystatic/src/app/updating.test.tsx
new file mode 100644
index 000000000..039edde95
--- /dev/null
+++ b/packages/keystatic/src/app/updating.test.tsx
@@ -0,0 +1,220 @@
+import { renderHook, act } from '@testing-library/react';
+import { webcrypto } from 'node:crypto';
+import { beforeEach, describe, expect, test, vi } from 'vitest';
+import { fields } from '../form/api';
+import { Config } from '..';
+import { treeEntriesToTreeNodes, TreeEntry } from './trees';
+import { getTreeKey } from './tree-key';
+
+// node only started setting the web crypto api globally in newer versions
+if (!globalThis.crypto) {
+  globalThis.crypto = webcrypto as any;
+}
+
+const mocks = vi.hoisted(() => ({
+  mutate: vi.fn(),
+  remoteHeads: [] as { oid: string; entries: TreeEntry[] }[],
+  fetchRef: vi.fn(),
+  fetchTree: vi.fn(),
+}));
+
+vi.mock('urql', () => ({
+  useMutation: () => [undefined, mocks.mutate],
+}));
+
+vi.mock('./provider', () => ({
+  createUrqlClient: () => ({
+    query: () => ({ toPromise: mocks.fetchRef }),
+  }),
+}));
+
+vi.mock('./shell/data', () => ({
+  useBaseCommit: () => 'opened-head',
+  useCurrentBranch: () => 'main',
+  useSetTreeSha: () => () => {},
+  useRepoInfo: () => ({
+    owner: 'owner',
+    name: 'repo',
+    hasWritePermission: true,
+  }),
+  useCurrentUnscopedTree: () => ({
+    kind: 'loaded',
+    data: { tree: treeEntriesToTreeNodes([]) },
+  }),
+  fetchGitHubTreeData: (...args: unknown[]) => mocks.fetchTree(...args),
+  hydrateTreeCacheWithEntries: async (entries: TreeEntry[]) => ({
+    entries: new Map(entries.map(e => [e.path, e])),
+    tree: treeEntriesToTreeNodes(entries),
+  }),
+}));
+
+vi.mock('./useItemData', () => ({
+  hydrateBlobCache: async () => 'blob-sha',
+}));
+
+// imported after the mocks are registered
+const { useUpsertItem } = await import('./updating');
+
+const config: Config = {
+  storage: { kind: 'github', repo: 'owner/repo' },
+  collections: {
+    posts: {
+      label: 'Posts',
+      slugField: 'title',
+      path: 'posts/*',
+      schema: { title: fields.slug({ name: { label: 'Title' } }) },
+    },
+  },
+};
+
+function entry(path: string, type: 'blob' | 'tree', sha: string): TreeEntry {
+  return {
+    path,
+    type,
+    sha,
+    mode: type === 'tree' ? '040000' : '100644',
+    size: 0,
+    url: '',
+  } as TreeEntry;
+}
+
+/** a remote tree containing the given post slugs (each one with a given sha) */
+function remoteTree(posts: Record<string, string> = {}, extra: string[] = []) {
+  const entries: TreeEntry[] = [entry('posts', 'tree', 'posts-dir')];
+  for (const [slug, sha] of Object.entries(posts)) {
+    entries.push(entry(`posts/${slug}`, 'tree', sha));
+    entries.push(entry(`posts/${slug}/index.yaml`, 'blob', `${sha}-file`));
+  }
+  for (const path of extra) entries.push(entry(path, 'blob', `${path}-sha`));
+  return entries;
+}
+
+function staleData() {
+  return {
+    error: {
+      graphQLErrors: [{ originalError: { type: 'STALE_DATA' } }],
+    },
+  };
+}
+
+const success = {
+  data: { createCommitOnBranch: { ref: { target: { oid: 'new-head' } } } },
+};
+
+function setRemoteHead(oid: string, entries: TreeEntry[]) {
+  mocks.fetchRef.mockResolvedValueOnce({
+    data: { repository: { ref: { target: { oid } } } },
+  });
+  mocks.fetchTree.mockImplementationOnce(async () => ({
+    entries: new Map(entries.map(e => [e.path, e])),
+    tree: treeEntriesToTreeNodes(entries),
+  }));
+}
+
+function renderUpsert(
+  currentLocalTreeKey: string | undefined,
+  slug = 'new-post'
+) {
+  return renderHook(() =>
+    useUpsertItem({
+      state: { title: { name: 'New post', slug } },
+      initialFiles: undefined,
+      schema: config.collections!.posts.schema,
+      config,
+      format: { data: 'yaml', contentField: undefined, dataLocation: 'index' },
+      currentLocalTreeKey,
+      basePath: `posts/${slug}`,
+      slug: { field: 'title', value: slug },
+    })
+  );
+}
+
+async function save(hook: ReturnType<typeof renderUpsert>) {
+  let result: boolean | undefined;
+  await act(async () => {
+    result = await hook.result.current[1]();
+  });
+  return { saved: result, state: hook.result.current[0] };
+}
+
+beforeEach(() => {
+  mocks.mutate.mockReset();
+  mocks.fetchRef.mockReset();
+  mocks.fetchTree.mockReset();
+});
+
+// CreateItemLocal and CreateItemCollab (create-item.tsx) both call
+// useUpsertItem with `currentLocalTreeKey: undefined`, which is what is
+// exercised in the "create" tests below.
+describe('creating an entry (no local tree key)', () => {
+  test('retries when an unrelated commit moved the branch head', async () => {
+    mocks.mutate
+      .mockResolvedValueOnce(staleData())
+      .mockResolvedValueOnce(success);
+    setRemoteHead('head-2', remoteTree({ other: 'other-sha' }, ['README.md']));
+
+    const { saved, state } = await save(renderUpsert(undefined));
+
+    expect(saved).toBe(true);
+    expect(state).toEqual({ kind: 'updated' });
+    expect(mocks.mutate).toHaveBeenCalledTimes(2);
+    expect(mocks.mutate.mock.calls[0][0].input.expectedHeadOid).toBe(
+      'opened-head'
+    );
+    expect(mocks.mutate.mock.calls[1][0].input.expectedHeadOid).toBe('head-2');
+  });
+
+  test('shows the new-branch dialog when the slug was created remotely', async () => {
+    mocks.mutate.mockResolvedValueOnce(staleData());
+    setRemoteHead('head-2', remoteTree({ 'new-post': 'created-elsewhere' }));
+
+    const { saved, state } = await save(renderUpsert(undefined));
+
+    expect(saved).toBe(false);
+    expect(state.kind).toBe('needs-new-branch');
+    expect(mocks.mutate).toHaveBeenCalledTimes(1);
+  });
+
+  test('errors instead of overwriting when the head moves again before the retry', async () => {
+    mocks.mutate
+      .mockResolvedValueOnce(staleData())
+      .mockResolvedValueOnce(staleData());
+    setRemoteHead('head-2', remoteTree({ other: 'other-sha' }));
+
+    const { saved, state } = await save(renderUpsert(undefined));
+
+    expect(saved).toBe(false);
+    expect(state.kind).toBe('error');
+    expect(mocks.mutate).toHaveBeenCalledTimes(2);
+    // the retry is pinned to the head that was checked, not "latest"
+    expect(mocks.mutate.mock.calls[1][0].input.expectedHeadOid).toBe('head-2');
+  });
+});
+
+describe('editing an entry (local tree key)', () => {
+  const localTree = treeEntriesToTreeNodes(remoteTree({ 'new-post': 'v1' }));
+  const localKey = getTreeKey(['posts/new-post'], localTree);
+
+  test('retries when the entry is unchanged remotely', async () => {
+    mocks.mutate
+      .mockResolvedValueOnce(staleData())
+      .mockResolvedValueOnce(success);
+    setRemoteHead('head-2', remoteTree({ 'new-post': 'v1', other: 'x' }));
+
+    const { saved } = await save(renderUpsert(localKey));
+
+    expect(saved).toBe(true);
+    expect(mocks.mutate).toHaveBeenCalledTimes(2);
+  });
+
+  test('shows the new-branch dialog when the entry changed remotely', async () => {
+    mocks.mutate.mockResolvedValueOnce(staleData());
+    setRemoteHead('head-2', remoteTree({ 'new-post': 'v2' }));
+
+    const { saved, state } = await save(renderUpsert(localKey));
+
+    expect(saved).toBe(false);
+    expect(state.kind).toBe('needs-new-branch');
+    expect(mocks.mutate).toHaveBeenCalledTimes(1);
+  });
+});
diff --git a/packages/keystatic/src/app/updating.tsx b/packages/keystatic/src/app/updating.tsx
index 0234dfef1..d9e87d11b 100644
--- a/packages/keystatic/src/app/updating.tsx
+++ b/packages/keystatic/src/app/updating.tsx
@@ -262,16 +262,21 @@ export function useUpsertItem(args: {
                 ),
                 args.config
               );
-              const treeKey = getTreeKey(
-                getDirectoriesForTreeKey(
-                  fields.object(args.schema),
-                  args.basePath,
-                  args.slug?.value,
-                  args.format
-                ),
-                tree.tree
+              const directoriesForTreeKey = getDirectoriesForTreeKey(
+                fields.object(args.schema),
+                args.basePath,
+                args.slug?.value,
+                args.format
               );
-              if (treeKey === args.currentLocalTreeKey) {
+              const treeKey = getTreeKey(directoriesForTreeKey, tree.tree);
+              // When creating an entry there is no local tree key, so the
+              // entry is expected to be absent from the remote branch. Only
+              // retry if that's still the case (i.e. the head moved because of
+              // an unrelated commit and nobody created this entry meanwhile).
+              const expectedTreeKey =
+                args.currentLocalTreeKey ??
+                getTreeKey(directoriesForTreeKey, new Map());
+              if (treeKey === expectedTreeKey) {
                 result = await runMutation(
                   refData.data.repository.ref.target.oid
                 );