diff --git a/x-pack/plugins/cases/common/constants/files.ts b/x-pack/plugins/cases/common/constants/files.ts
index 7f3f355aff1a9..2043d3f79a41e 100644
--- a/x-pack/plugins/cases/common/constants/files.ts
+++ b/x-pack/plugins/cases/common/constants/files.ts
@@ -10,4 +10,4 @@ export const FILE_ATTACHMENT_TYPE = '.files';
 export const MAX_FILE_SIZE = 100 * 1024 * 1024; // 100 MiB
 export const MAX_IMAGE_FILE_SIZE = 10 * 1024 * 1024; // 10 MiB
 export const MAX_FILES_PER_CASE = 100;
-export const MAX_DELETE_FILES = 50;
+export const MAX_DELETE_FILES = 10;
diff --git a/x-pack/plugins/cases/server/client/attachments/bulk_delete.test.ts b/x-pack/plugins/cases/server/client/attachments/bulk_delete.test.ts
index 49a12c904eb63..a5188b6a7b803 100644
--- a/x-pack/plugins/cases/server/client/attachments/bulk_delete.test.ts
+++ b/x-pack/plugins/cases/server/client/attachments/bulk_delete.test.ts
@@ -9,9 +9,32 @@ import { loggerMock } from '@kbn/logging-mocks';
 import pReflect from 'p-reflect';
 import type { File } from '@kbn/files-plugin/common';
 import { FileNotFoundError } from '@kbn/files-plugin/server/file_service/errors';
-import { retrieveFilesIgnoringNotFound } from './bulk_delete';
+import { bulkDeleteFileAttachments, retrieveFilesIgnoringNotFound } from './bulk_delete';
+import { MAX_DELETE_FILES } from '../../../common/constants';
+import { createCasesClientMock, createCasesClientMockArgs } from '../mocks';
 
 describe('bulk_delete', () => {
+  describe('bulkDeleteFileAttachments', () => {
+    describe('errors', () => {
+      const casesClient = createCasesClientMock();
+      const clientArgs = createCasesClientMockArgs();
+
+      beforeEach(() => {
+        jest.clearAllMocks();
+      });
+
+      it(`throws 400 when trying to delete more than ${MAX_DELETE_FILES} files at a time`, async () => {
+        const fileIds = new Array(MAX_DELETE_FILES + 1).fill('fake-ids');
+
+        await expect(
+          bulkDeleteFileAttachments({ caseId: 'mock-id-4', fileIds }, clientArgs, casesClient)
+        ).rejects.toThrowError(
+          'Failed to delete file attachments for case: mock-id-4: Error: array must be of length <= 10'
+        );
+      });
+    });
+  });
+
   describe('retrieveFilesIgnoringNotFound', () => {
     const mockLogger = loggerMock.create();