diff --git a/.changeset/chatty-pens-try.md b/.changeset/chatty-pens-try.md
new file mode 100644
index 0000000000..1c92bb82cb
--- /dev/null
+++ b/.changeset/chatty-pens-try.md
@@ -0,0 +1,6 @@
+---
+'@backstage/integration': patch
+---
+
+Do not return a token rather than fail where the owner is not in the allowed installation owners
+for a GitHub app. This allows anonymous access to public files in the organisation.
diff --git a/packages/integration/src/github/SingleInstanceGithubCredentialsProvider.test.ts b/packages/integration/src/github/SingleInstanceGithubCredentialsProvider.test.ts
index e5c6307338..246a859b7a 100644
--- a/packages/integration/src/github/SingleInstanceGithubCredentialsProvider.test.ts
+++ b/packages/integration/src/github/SingleInstanceGithubCredentialsProvider.test.ts
@@ -136,6 +136,44 @@ describe('SingleInstanceGithubCredentialsProvider tests', () => {
     expect(token).toEqual('secret_token');
   });
 
+  it('does not return a token where the organisation is not in the allowedInstallationsList', async () => {
+    github = SingleInstanceGithubCredentialsProvider.create({
+      host: 'github.com',
+      apps: [
+        {
+          appId: 1,
+          privateKey: 'privateKey',
+          webhookSecret: '123',
+          clientId: 'CLIENT_ID',
+          clientSecret: 'CLIENT_SECRET',
+          allowedInstallationOwners: ['backstage'],
+        },
+      ],
+    });
+
+    octokit.apps.listInstallations.mockResolvedValue({
+      headers: {
+        etag: '123',
+      },
+      data: [
+        {
+          id: 1,
+          repository_selection: 'all',
+          account: {
+            login: 'backstage',
+          },
+        },
+      ],
+    } as RestEndpointMethodTypes['apps']['listInstallations']['response']);
+
+    const { token, headers } = await github.getCredentials({
+      url: 'https://github.com/RoadiehHQ',
+    });
+
+    expect(headers).toEqual(undefined);
+    expect(token).toEqual(undefined);
+  });
+
   it('should not fail to issue tokens for an organization when the app is installed for a single repo', async () => {
     octokit.apps.listInstallations.mockResolvedValue({
       headers: {
diff --git a/packages/integration/src/github/SingleInstanceGithubCredentialsProvider.ts b/packages/integration/src/github/SingleInstanceGithubCredentialsProvider.ts
index 408c5b1348..bfc360cbe2 100644
--- a/packages/integration/src/github/SingleInstanceGithubCredentialsProvider.ts
+++ b/packages/integration/src/github/SingleInstanceGithubCredentialsProvider.ts
@@ -92,13 +92,11 @@ class GithubAppManager {
   async getInstallationCredentials(
     owner: string,
     repo?: string,
-  ): Promise<{ accessToken: string }> {
+  ): Promise<{ accessToken: string | undefined }> {
     const { installationId, suspended } = await this.getInstallationData(owner);
     if (this.allowedInstallationOwners) {
       if (!this.allowedInstallationOwners?.includes(owner)) {
-        throw new Error(
-          `The GitHub application for ${owner} is not included in the allowed installation list (${installationId}).`,
-        );
+        return { accessToken: undefined }; // An empty token allows anonymous access to public repos
       }
     }
     if (suspended) {