diff --git a/src/__snapshots__/markdown-renderer.spec.ts.snap b/src/__snapshots__/markdown-renderer.spec.ts.snap
index 550e411..3e27377 100644
--- a/src/__snapshots__/markdown-renderer.spec.ts.snap
+++ b/src/__snapshots__/markdown-renderer.spec.ts.snap
@@ -54,6 +54,12 @@ exports[`MarkdownRenderer > renderContributionList > renders a list of contribut
 * [#42](http://github.com/42) My cool PR ([@hzoo](http://hzoo.com))"
 `;
 
+exports[`MarkdownRenderer > renderContributorList > renders a list mixing a fallback (unfetchable) contributor with a full contributor 1`] = `
+"#### Committers: 2
+- @deleted-user
+- Tobias Bieniek (@Turbo87)"
+`;
+
 exports[`MarkdownRenderer > renderContributorList > renders a list of GitHub users 1`] = `
 "#### Committers: 2
 - Tobias Bieniek ([@Turbo87](https://github.com/Turbo87))
diff --git a/src/changelog.spec.js b/src/changelog.spec.js
index d0b1fdd..ec13a5d 100644
--- a/src/changelog.spec.js
+++ b/src/changelog.spec.js
@@ -278,5 +278,196 @@ describe('Changelog', () => {
         },
       ]);
     });
+    it('falls back gracefully when getUserData throws for a bot account (403)', async () => {
+      fetch.__setMockResponses({
+        'https://api.github.com/users/test-user-1': {
+          body: {
+            login: 'test-user-1',
+            html_url: 'https://github.com/test-user-1',
+            name: 'Test User 1',
+          },
+        },
+
+        // Simulate 403 - token lacks scope to fetch this bot's profile
+        'https://api.github.com/users/github-actions': {
+          status: 403,
+          statusText: 'Forbidden',
+          ok: false,
+          body: {
+            message: 'Resource not accessible by integration',
+          },
+        },
+      });
+
+      const changelog = new Changelog({ ignoreCommitters: [] });
+
+      const testCommits = [
+        {
+          commitSHA: 'a0000001',
+          githubIssue: {
+            user: {
+              login: 'test-user-1',
+              html_url: 'https://github.com/test-user-1',
+            },
+          },
+        },
+        {
+          commitSHA: 'a0000002',
+          githubIssue: {
+            user: {
+              login: 'github-actions',
+              html_url: 'https://github.com/apps/github-actions',
+            },
+          },
+        },
+      ];
+
+      const committers = await changelog.getCommitters(testCommits);
+
+      expect(committers).toHaveLength(2);
+
+      expect(committers[0]).toEqual({
+        login: 'test-user-1',
+        html_url: 'https://github.com/test-user-1',
+        name: 'Test User 1',
+      });
+
+      // Falls back to login-only — no name, no type, html_url preserved from PR data
+      expect(committers[1]).toEqual({
+        login: 'github-actions',
+        html_url: 'https://github.com/apps/github-actions',
+      });
+    });
+    it('ignoreCommitters still works when mixed with failing getUserData', async () => {
+      fetch.__setMockResponses({
+        'https://api.github.com/users/real-user': {
+          body: {
+            login: 'real-user',
+            html_url: 'https://github.com/real-user',
+            name: 'Real User',
+          },
+        },
+      });
+
+      // ignored-bot is in ignoreCommitters: getUserData should never be called for it
+      const changelog = new Changelog({
+        ignoreCommitters: ['ignored-bot'],
+      });
+
+      const testCommits = [
+        {
+          commitSHA: 'a0000001',
+          githubIssue: {
+            user: {
+              login: 'real-user',
+              html_url: 'https://github.com/real-user',
+            },
+          },
+        },
+        {
+          commitSHA: 'a0000002',
+          githubIssue: {
+            user: {
+              login: 'ignored-bot',
+              html_url: 'https://github.com/ignored-bot',
+            },
+          },
+        },
+      ];
+
+      const committers = await changelog.getCommitters(testCommits);
+
+      // ignored-bot skipped before getUserData is even attempted
+      expect(committers).toHaveLength(1);
+
+      expect(committers[0]).toEqual({
+        login: 'real-user',
+        html_url: 'https://github.com/real-user',
+        name: 'Real User',
+      });
+    });
+    it('falls back with empty html_url when PR user data has none', async () => {
+      fetch.__setMockResponses({});
+
+      // ignored-bot is in ignoreCommitters: getUserData should never be called for it
+      const changelog = new Changelog({
+        ignoreCommitters: [],
+      });
+
+      const testCommits = [
+        {
+          commitSHA: 'a0000001',
+          githubIssue: {
+            user: {
+              login: 'restricted-bot',
+            },
+          },
+        },
+      ];
+
+      const committers = await changelog.getCommitters(testCommits);
+
+      // ignored-bot skipped before getUserData is even attempted
+      expect(committers).toHaveLength(1);
+
+      expect(committers[0]).toEqual({
+        login: 'restricted-bot',
+        html_url: '',
+      });
+    });
+    it('falls back with gracefully when getUserData throws for a deleted user', async () => {
+      fetch.__setMockResponses({
+        'https://api.github.com/users/test-user1': {
+          body: {
+            login: 'test-user1',
+            html_url: 'https://github.com/test-user1',
+            name: 'Test User 1',
+          },
+        },
+        // Simulate 404 - account was deleted aftr the pr was merged
+        'https://api.github.com/users/deleted-user': {
+          status: 404,
+          statusText: 'Not Found',
+          ok: false,
+          body: { message: 'Not Found' },
+        },
+      });
+      const changelog = new Changelog({ ignoreCommitters: [] });
+      const testCommits = [
+        {
+          commitSHA: 'a0000001',
+          githubIssue: {
+            user: {
+              login: 'test-user1',
+              html_url: 'https://github.com/test-user1',
+            },
+          },
+        },
+        {
+          commitSHA: 'a0000002',
+          githubIssue: {
+            user: {
+              login: 'deleted-user',
+              html_url: 'https://github.com/deleted-user',
+            },
+          },
+        },
+      ];
+
+      const committers = await changelog.getCommitters(testCommits);
+
+      expect(committers).toHaveLength(2);
+
+      expect(committers[0]).toEqual({
+        login: 'test-user1',
+        html_url: 'https://github.com/test-user1',
+        name: 'Test User 1',
+      });
+      // Deleted account - falls back to login-only, html-url from PR data, no name
+      expect(committers[1]).toEqual({
+        login: 'deleted-user',
+        html_url: 'https://github.com/deleted-user',
+      });
+    });
   });
 });
diff --git a/src/changelog.ts b/src/changelog.ts
index f867ea1..e58aee1 100644
--- a/src/changelog.ts
+++ b/src/changelog.ts
@@ -136,7 +136,17 @@ export default class Changelog {
       const shouldKeepCommiter = login && !this.ignoreCommitter(login);
 
       if (login && shouldKeepCommiter && !committers[login]) {
-        committers[login] = this.sanitizeCommitter(await this.github.getUserData(user));
+        try {
+          committers[login] = this.sanitizeCommitter(await this.github.getUserData(user));
+        } catch {
+          // getUserData can fail for various reasons (e.g. 403 for restricted bot accounts or 404 for deleted accounts).
+          // Fall back to a minimal entry using just the login
+          // so the changelog still generates rather than failing completely.
+          committers[login] = {
+            login,
+            html_url: user.html_url || '',
+          } as GitHubContributor;
+        }
       }
     }
 
diff --git a/src/functional/__snapshots__/markdown-unfetchable-comitter.spec.js.snap b/src/functional/__snapshots__/markdown-unfetchable-comitter.spec.js.snap
new file mode 100644
index 0000000..c79c621
--- /dev/null
+++ b/src/functional/__snapshots__/markdown-unfetchable-comitter.spec.js.snap
@@ -0,0 +1,13 @@
+// Vitest Snapshot v1, https://vitest.dev/guide/snapshot.html
+
+exports[`createMarkdown with an unfetchable committer > still generates a readable changelog when a bot committer is unfetchable 1`] = `
+"
+## Unreleased (2099-01-01)
+
+#### :house: Maintenance
+* [#2](https://github.com/embroider-build/github-changelog/pull/2) chore: bump dependencies ([@dependabot[bot]](https://github.com/apps/dependabot))
+
+#### Committers: 2
+- Real User ([@real-user](https://github.com/real-user))
+- [@dependabot[bot]](https://github.com/apps/dependabot)"
+`;
diff --git a/src/functional/markdown-unfetchable-comitter.spec.js b/src/functional/markdown-unfetchable-comitter.spec.js
new file mode 100644
index 0000000..0490069
--- /dev/null
+++ b/src/functional/markdown-unfetchable-comitter.spec.js
@@ -0,0 +1,71 @@
+import { vi, describe, beforeEach, afterEach, it, expect } from 'vitest';
+
+import * as git from '../git';
+import Changelog from '../changelog';
+import * as fetch from '../fetch';
+
+vi.mock('../../src/progress-bar');
+vi.mock('../changelog');
+vi.mock('../../src/github-api');
+vi.mock('../git');
+vi.mock('../fetch');
+
+describe('createMarkdown with an unfetchable committer', () => {
+  beforeEach(() => {
+    fetch.__resetMockResponses();
+
+    git.changedPaths.mockImplementation(() => []);
+    git.lastTag.mockImplementation(() => 'v1.0.0');
+    git.listTagNames.mockImplementation(() => ['v1.0.0']);
+    git.listCommits.mockImplementation(() => [
+      {
+        sha: 'a0000002',
+        refName: '',
+        summary: 'Merge pull request #2 from bump-deps',
+        date: '2024-01-02',
+      },
+      {
+        sha: 'a0000001',
+        refName: '',
+        summary: 'Merge pull request #1 from feature',
+        date: '2024-01-01',
+      },
+    ]);
+
+    fetch.__setMockResponses({
+      'https://api.github.com/repos/embroider-build/github-changelog/issues/1': {
+        body: {
+          number: 1,
+          title: 'feat: add new feature',
+          labels: [{ name: 'New Feature' }],
+          pull_request: { html_url: 'https://github.com/embroider-build/github-changelog/pull/1' },
+          user: { login: 'real-user', html_url: 'https://github.com/real-user' },
+        },
+      },
+      'https://api.github.com/repos/embroider-build/github-changelog/issues/2': {
+        body: {
+          number: 2,
+          title: 'chore: bump dependencies',
+          labels: [{ name: 'Type: Maintenance' }],
+          pull_request: { html_url: 'https://github.com/embroider-build/github-changelog/pull/2' },
+          user: { login: 'dependabot[bot]', html_url: 'https://github.com/apps/dependabot' },
+        },
+      },
+      'https://api.github.com/users/real-user': {
+        body: { login: 'real-user', type: 'User', html_url: 'https://github.com/real-user', name: 'Real User' },
+      },
+    });
+  });
+
+  afterEach(() => {
+    vi.resetAllMocks();
+  });
+
+  it('still generates a readable changelog when a bot committer is unfetchable', async () => {
+    const changelog = new Changelog({ ignoreCommitters: [] });
+
+    const markdown = await changelog.createMarkdown();
+
+    expect(markdown).toMatchSnapshot();
+  });
+});
diff --git a/src/markdown-renderer.spec.ts b/src/markdown-renderer.spec.ts
index 71bbf00..00223e6 100644
--- a/src/markdown-renderer.spec.ts
+++ b/src/markdown-renderer.spec.ts
@@ -1,4 +1,4 @@
-import type { GithubAppInfo } from './github-api.js';
+import type { GithubAppInfo, GitHubContributor } from './github-api.js';
 import { CommitInfo, Release } from './interfaces.js';
 import MarkdownRenderer from './markdown-renderer.js';
 
@@ -136,6 +136,24 @@ describe('MarkdownRenderer', () => {
 
       expect(result).toMatchSnapshot();
     });
+
+    it('renders a list mixing a fallback (unfetchable) contributor with a full contributor', () => {
+      const fallbackContributor = {
+        login: 'deleted-user',
+        html_url: '',
+      } as GitHubContributor;
+
+      const fullContributor = {
+        login: 'Turbo87',
+        name: 'Tobias Bieniek',
+        type: 'User',
+        html_url: '',
+      } as GitHubContributor;
+
+      const result = renderer().renderContributorList([fallbackContributor, fullContributor]);
+
+      expect(result).toMatchSnapshot();
+    });
   });
 
   describe('renderContributor', () => {
@@ -171,6 +189,24 @@ describe('MarkdownRenderer', () => {
 
       expect(result).toEqual('Copilot [Bot] ([@copilot-swe-agent](https://github.com/apps/copilot-swe-agent))');
     });
+
+    it(`renders a fallback contributor that has an html_url`, () => {
+      const result = renderer().renderContributor({
+        login: 'github-actions',
+        html_url: 'https://github.com/apps/github-actions',
+      } as GitHubContributor);
+
+      expect(result).toEqual('[@github-actions](https://github.com/apps/github-actions)');
+    });
+
+    it(`renders a fallback contributor with no html_url as a plain mention`, () => {
+      const result = renderer().renderContributor({
+        login: 'deleted-user',
+        html_url: '',
+      } as GitHubContributor);
+
+      expect(result).toEqual('@deleted-user');
+    });
   });
 
   describe('groupByCategory', () => {
diff --git a/src/markdown-renderer.ts b/src/markdown-renderer.ts
index 5b76c9e..b9d3b71 100644
--- a/src/markdown-renderer.ts
+++ b/src/markdown-renderer.ts
@@ -122,7 +122,9 @@ export default class MarkdownRenderer {
 
   public renderContributor(contributor: GitHubContributor): string {
     const userName = (contributor as GithubAppInfo).slug ?? (contributor as GithubUserInfo).login;
-    const userNameAndLink = `[@${userName}](${contributor.html_url})`;
+    // html_url can be empty when getCommiters falls back for unfetchable committers (e.g. deleted users, restricted users).
+    // Render a plain @login metion instead of a markdown link with an empty href.
+    const userNameAndLink = contributor.html_url ? `[@${userName}](${contributor.html_url})` : `@${userName}`;
 
     if (contributor.name) {
       const name = contributor.name + (!('type' in contributor) ? ' [Bot]' : '');