diff --git a/app/Http/Controllers/Webhook/Github.php b/app/Http/Controllers/Webhook/Github.php
index 28e92dcd4..c4fdc5fd5 100644
--- a/app/Http/Controllers/Webhook/Github.php
+++ b/app/Http/Controllers/Webhook/Github.php
@@ -83,7 +83,10 @@ public function manual(Request $request)
                 }
             }
             if ($x_github_event === 'pull_request') {
-                $applications = $this->manualWebhookApplications($applications->where('git_branch', $base_branch), $full_name);
+                if ($action !== 'closed') {
+                    $applications->where('git_branch', $base_branch);
+                }
+                $applications = $this->manualWebhookApplications($applications, $full_name);
                 if ($applications->isEmpty()) {
                     return response("Nothing to do. No applications found for repo $full_name and branch '$base_branch'.");
                 }
@@ -334,7 +337,10 @@ public function normal(Request $request)
                 }
             }
             if ($x_github_event === 'pull_request') {
-                $applications = $applications->where('git_branch', $base_branch)->get();
+                if ($action !== 'closed') {
+                    $applications->where('git_branch', $base_branch);
+                }
+                $applications = $applications->get();
                 if ($applications->isEmpty()) {
                     return response("Nothing to do. No applications found with branch '$base_branch'.");
                 }
diff --git a/tests/Feature/GithubPullRequestWebhookRoutingTest.php b/tests/Feature/GithubPullRequestWebhookRoutingTest.php
new file mode 100644
index 000000000..7768dbd90
--- /dev/null
+++ b/tests/Feature/GithubPullRequestWebhookRoutingTest.php
@@ -0,0 +1,156 @@
+<?php
+
+use App\Jobs\ProcessGithubPullRequestWebhook;
+use App\Models\Application;
+use App\Models\Environment;
+use App\Models\GithubApp;
+use App\Models\Project;
+use App\Models\Server;
+use App\Models\Team;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Facades\Queue;
+
+uses(RefreshDatabase::class);
+
+function createGithubPullRequestWebhookApplication(array $overrides = []): Application
+{
+    $team = Team::factory()->create();
+    $project = Project::factory()->create(['team_id' => $team->id]);
+    $environment = Environment::factory()->create(['project_id' => $project->id]);
+    $server = Server::factory()->create(['team_id' => $team->id]);
+    $server->settings->update([
+        'is_reachable' => true,
+        'is_usable' => true,
+        'force_disabled' => false,
+    ]);
+    $destination = $server->standaloneDockers()->firstOrFail();
+
+    return Application::create(array_merge([
+        'name' => 'github-pr-webhook-app',
+        'git_repository' => 'https://github.com/test-org/test-repo',
+        'git_branch' => 'main',
+        'build_pack' => 'nixpacks',
+        'ports_exposes' => '3000',
+        'environment_id' => $environment->id,
+        'destination_id' => $destination->id,
+        'destination_type' => $destination->getMorphClass(),
+    ], $overrides));
+}
+
+function githubPullRequestPayload(string $action, string $baseBranch): array
+{
+    return [
+        'action' => $action,
+        'number' => 42,
+        'repository' => [
+            'id' => 987654321,
+            'full_name' => 'test-org/test-repo',
+        ],
+        'pull_request' => [
+            'html_url' => 'https://github.com/test-org/test-repo/pull/42',
+            'title' => 'Stacked change',
+            'author_association' => 'OWNER',
+            'head' => [
+                'ref' => 'feature/child',
+                'sha' => 'head-sha',
+            ],
+            'base' => [
+                'ref' => $baseBranch,
+            ],
+        ],
+    ];
+}
+
+it('routes a closed GitHub App pull request to its application after the base branch changes', function () {
+    Queue::fake();
+
+    $team = Team::factory()->create();
+    $githubApp = GithubApp::create([
+        'name' => 'github-app-webhook-test',
+        'api_url' => 'https://api.github.com',
+        'html_url' => 'https://github.com',
+        'app_id' => 1234567890,
+        'webhook_secret' => 'test-secret',
+        'is_public' => false,
+        'team_id' => $team->id,
+    ]);
+    $application = createGithubPullRequestWebhookApplication([
+        'repository_project_id' => 987654321,
+        'source_id' => $githubApp->id,
+        'source_type' => GithubApp::class,
+    ]);
+
+    $body = json_encode(githubPullRequestPayload('closed', 'feature/parent'), JSON_THROW_ON_ERROR);
+    $response = $this->call('POST', '/webhooks/source/github/events', [], [], [], [
+        'HTTP_X-GitHub-Event' => 'pull_request',
+        'HTTP_X-GitHub-Hook-Installation-Target-Id' => '1234567890',
+        'HTTP_X-Hub-Signature-256' => 'sha256='.hash_hmac('sha256', $body, 'test-secret'),
+        'CONTENT_TYPE' => 'application/json',
+    ], $body);
+
+    $response->assertOk();
+    expect($response->getContent())->toContain('PR webhook received');
+    Queue::assertPushed(ProcessGithubPullRequestWebhook::class, fn (ProcessGithubPullRequestWebhook $job): bool => $job->applicationId === $application->id
+        && $job->action === 'closed'
+        && $job->pullRequestId === 42);
+});
+
+it('routes a closed manual pull request to its application after the base branch changes', function () {
+    Queue::fake();
+
+    $application = createGithubPullRequestWebhookApplication();
+    $payload = githubPullRequestPayload('closed', 'feature/parent');
+    $body = json_encode($payload, JSON_THROW_ON_ERROR);
+
+    $response = $this->call('POST', '/webhooks/source/github/events/manual', [], [], [], [
+        'HTTP_X-GitHub-Event' => 'pull_request',
+        'HTTP_X-Hub-Signature-256' => 'sha256='.hash_hmac('sha256', $body, $application->manual_webhook_secret_github),
+        'CONTENT_TYPE' => 'application/json',
+    ], $body);
+
+    $response->assertOk();
+    Queue::assertPushed(ProcessGithubPullRequestWebhook::class, fn (ProcessGithubPullRequestWebhook $job): bool => $job->applicationId === $application->id
+        && $job->action === 'closed'
+        && $job->pullRequestId === 42);
+});
+
+it('continues to filter non-closed pull requests by base branch', function (string $endpoint) {
+    Queue::fake();
+
+    if ($endpoint === 'app') {
+        $team = Team::factory()->create();
+        $githubApp = GithubApp::create([
+            'name' => 'github-app-webhook-test',
+            'api_url' => 'https://api.github.com',
+            'html_url' => 'https://github.com',
+            'app_id' => 1234567890,
+            'webhook_secret' => 'test-secret',
+            'is_public' => false,
+            'team_id' => $team->id,
+        ]);
+        createGithubPullRequestWebhookApplication([
+            'repository_project_id' => 987654321,
+            'source_id' => $githubApp->id,
+            'source_type' => GithubApp::class,
+        ]);
+
+        $body = json_encode(githubPullRequestPayload('opened', 'feature/parent'), JSON_THROW_ON_ERROR);
+        $response = $this->call('POST', '/webhooks/source/github/events', [], [], [], [
+            'HTTP_X-GitHub-Event' => 'pull_request',
+            'HTTP_X-GitHub-Hook-Installation-Target-Id' => '1234567890',
+            'HTTP_X-Hub-Signature-256' => 'sha256='.hash_hmac('sha256', $body, 'test-secret'),
+            'CONTENT_TYPE' => 'application/json',
+        ], $body);
+    } else {
+        $application = createGithubPullRequestWebhookApplication();
+        $body = json_encode(githubPullRequestPayload('opened', 'feature/parent'), JSON_THROW_ON_ERROR);
+        $response = $this->call('POST', '/webhooks/source/github/events/manual', [], [], [], [
+            'HTTP_X-GitHub-Event' => 'pull_request',
+            'HTTP_X-Hub-Signature-256' => 'sha256='.hash_hmac('sha256', $body, $application->manual_webhook_secret_github),
+            'CONTENT_TYPE' => 'application/json',
+        ], $body);
+    }
+
+    $response->assertOk();
+    Queue::assertNotPushed(ProcessGithubPullRequestWebhook::class);
+})->with(['app', 'manual']);