diff --git a/app/Http/Controllers/Api/DatabasesController.php b/app/Http/Controllers/Api/DatabasesController.php
index 0a34c54239..7d103d7d52 100644
--- a/app/Http/Controllers/Api/DatabasesController.php
+++ b/app/Http/Controllers/Api/DatabasesController.php
@@ -1244,6 +1244,7 @@ class DatabasesController extends Controller
         if (! isset($backupData['enabled'])) {
             $backupData['enabled'] = true;
         }
+        $backupData['save_s3'] ??= false;
 
         if ($s3Storages?->isNotEmpty()) {
             $this->authorize('useTeamCredentials', $database);
diff --git a/app/Livewire/Project/Database/BackupEdit.php b/app/Livewire/Project/Database/BackupEdit.php
index f987003052..bfbd1ad164 100644
--- a/app/Livewire/Project/Database/BackupEdit.php
+++ b/app/Livewire/Project/Database/BackupEdit.php
@@ -192,6 +192,10 @@ class BackupEdit extends Component
             // The team of the schedule, because the instance database has no environment to read it from.
             if ($this->backup->newS3StorageIds($storageIds)->isNotEmpty()
                 && ! app(AccessResolver::class)->allowsTeamWide(Auth::user(), AccessLevel::Write, (int) $this->backup->team_id)) {
+                $this->backup->refresh();
+                $this->saveS3 = (bool) $this->backup->save_s3;
+                $this->s3StorageIds = $this->backup->selectedS3Storages()->pluck('id')->all();
+
                 throw new AuthorizationException('You need write access on the whole team to add an S3 storage to this backup.');
             }
             $changedFields = auditChangedFields($this->backup);
diff --git a/app/Policies/ResourceCreatePolicy.php b/app/Policies/ResourceCreatePolicy.php
index e8dd00cf9d..6ac1c10115 100644
--- a/app/Policies/ResourceCreatePolicy.php
+++ b/app/Policies/ResourceCreatePolicy.php
@@ -6,6 +6,7 @@ use App\Enums\AccessLevel;
 use App\Models\Environment;
 use App\Models\User;
 use App\Services\Access\AccessResolver;
+use Illuminate\Auth\Access\Response;
 use Illuminate\Database\Eloquent\Model;
 
 class ResourceCreatePolicy
@@ -30,10 +31,12 @@ class ResourceCreatePolicy
      * yet: private keys, git sources, integration tokens, and backup files of other resources.
      * Needs write access on the whole team of the resource, or of the current team without a resource.
      */
-    public function useTeamCredentials(User $user, ?Model $resource = null): bool
+    public function useTeamCredentials(User $user, ?Model $resource = null): Response
     {
         $teamId = $resource !== null ? $resource->team()?->id : $user->currentTeam()?->id;
 
-        return $teamId !== null && app(AccessResolver::class)->allowsTeamWide($user, AccessLevel::Write, (int) $teamId);
+        return $teamId !== null && app(AccessResolver::class)->allowsTeamWide($user, AccessLevel::Write, (int) $teamId)
+            ? Response::allow()
+            : Response::deny('You need write access on the whole team to use team credentials, such as private keys, git sources, and S3 storages.');
     }
 }
diff --git a/tests/Feature/Access/ResourcePlacementTest.php b/tests/Feature/Access/ResourcePlacementTest.php
index 5e207c72d4..d5b1557c64 100644
--- a/tests/Feature/Access/ResourcePlacementTest.php
+++ b/tests/Feature/Access/ResourcePlacementTest.php
@@ -236,7 +236,8 @@ describe('team credentials in the API', function () {
         ];
 
         placementTestApi($this->developerToken, 'POST', '/api/v1/applications/private-deploy-key', [...$request, 'private_key_uuid' => $privateKey->uuid])
-            ->assertForbidden();
+            ->assertForbidden()
+            ->assertJsonPath('message', 'You need write access on the whole team to use team credentials, such as private keys, git sources, and S3 storages.');
         placementTestApi($this->developerToken, 'POST', '/api/v1/applications/private-github-app', [...$request, 'github_app_uuid' => 'any-github-app'])
             ->assertForbidden();
 
@@ -314,6 +315,26 @@ describe('team S3 storages for backups', function () {
             ->and((bool) $backup->fresh()->save_s3)->toBeFalse();
     });
 
+    test('the backup page shows one error when a project-scoped member selects a team S3 storage', function () {
+        $backup = ScheduledDatabaseBackup::create([
+            'frequency' => '0 0 * * *',
+            'save_s3' => false,
+            'database_type' => $this->database->getMorphClass(),
+            'database_id' => $this->database->id,
+            'team_id' => $this->team->id,
+        ]);
+        $this->actingAs($this->developer);
+        session(['currentTeam' => $this->team]);
+
+        $component = Livewire::test(BackupEdit::class, ['backup' => $backup->fresh(), 'availableS3Storages' => collect()])
+            ->set('s3StorageIds', [$this->firstStorage->id]);
+
+        $errors = collect($component->effects['dispatches'] ?? [])->where('name', 'error');
+        expect($errors)->toHaveCount(1)
+            ->and($backup->fresh()->s3Storages()->count())->toBe(0);
+        $component->assertSet('s3StorageIds', [])->assertSet('saveS3', false);
+    });
+
     test('a member with team-wide write can send a backup schedule to a team S3 storage', function () {
         $operator = placementTestMember($this->team, [['scope' => 'team', 'uuid' => null, 'levels' => ['write', 'deploy', 'delete']]]);
 
diff --git a/tests/Feature/Api/DatabaseBackupCreationApiTest.php b/tests/Feature/Api/DatabaseBackupCreationApiTest.php
index 9a5cdc90c9..cb36558935 100644
--- a/tests/Feature/Api/DatabaseBackupCreationApiTest.php
+++ b/tests/Feature/Api/DatabaseBackupCreationApiTest.php
@@ -80,6 +80,16 @@ function backupHeaders(): array
 }
 
 describe('POST /api/v1/databases/{uuid}/backups', function () {
+    test('does not save to S3 when save_s3 is not sent', function () {
+        $this->withHeaders(backupHeaders())
+            ->postJson("/api/v1/databases/{$this->database->uuid}/backups", ['frequency' => 'daily'])
+            ->assertCreated();
+
+        $backup = ScheduledDatabaseBackup::firstOrFail();
+        expect((bool) $backup->save_s3)->toBeFalse()
+            ->and($backup->s3_storage_id)->toBeNull();
+    });
+
     test('rejects backup configurations for unsupported database types', function () {
         $database = StandaloneRedis::create([
             'uuid' => (string) Str::uuid(),