diff --git a/src/app/drive/services/thumbnail.service.test.ts b/src/app/drive/services/thumbnail.service.test.ts
index 4759e93c9..d750b2f3b 100644
--- a/src/app/drive/services/thumbnail.service.test.ts
+++ b/src/app/drive/services/thumbnail.service.test.ts
@@ -1,9 +1,14 @@
 import { afterEach, beforeEach, describe, expect, test, vi } from 'vitest';
 import Resizer from 'react-image-file-resizer';
 import { ErrorLoadingVideoFileError } from './errors/thumbnail.service.errors';
-import { getVideoFrame, getImageThumbnail } from './thumbnail.service';
+import { getVideoFrame, getImageThumbnail, downloadThumbnail } from './thumbnail.service';
+import localStorageService from 'services/local-storage.service';
+import fetchFileBlob from './download.service/fetchFileBlob';
+import { Thumbnail } from '@internxt/sdk/dist/drive/storage/types';
 
 vi.mock('react-image-file-resizer');
+vi.mock('services/local-storage.service');
+vi.mock('./download.service/fetchFileBlob');
 
 const flushPromises = () => new Promise((resolve) => setTimeout(resolve, 0));
 
@@ -240,4 +245,79 @@ describe('Thumbnail Service', () => {
       expect(result).toBeNull();
     });
   });
+
+  describe('Download Thumbnail', () => {
+    const workspaceBucket = 'workspace-bucket-123';
+    const personalBucket = 'personal-bucket-456';
+
+    const mockThumbnail: Thumbnail = {
+      id: 1,
+      file_id: 123,
+      bucket_id: workspaceBucket,
+      bucket_file: 'bucket-file-hash',
+      type: 'image/png',
+      size: 1024,
+      max_width: 300,
+      max_height: 300,
+      encrypt_version: '03-aes',
+    };
+
+    beforeEach(() => {
+      vi.clearAllMocks();
+      vi.mocked(fetchFileBlob).mockResolvedValue(new Blob(['thumbnail-data']));
+    });
+
+    test('When downloading thumbnail in workspace context with workspace bucket, then it uses workspace credentials', async () => {
+      vi.mocked(localStorageService.getUser).mockReturnValue({ bucket: personalBucket } as any);
+
+      await downloadThumbnail(mockThumbnail, true);
+
+      expect(fetchFileBlob).toHaveBeenCalledWith(
+        expect.objectContaining({
+          fileId: mockThumbnail.bucket_file,
+          bucketId: mockThumbnail.bucket_id,
+        }),
+        expect.objectContaining({
+          isWorkspace: true,
+        }),
+      );
+    });
+
+    test('When downloading thumbnail in workspace context with personal bucket, then it uses personal credentials for backward compatibility', async () => {
+      const thumbnailInPersonalBucket: Thumbnail = {
+        ...mockThumbnail,
+        bucket_id: personalBucket,
+      };
+
+      vi.mocked(localStorageService.getUser).mockReturnValue({ bucket: personalBucket } as any);
+
+      await downloadThumbnail(thumbnailInPersonalBucket, true);
+
+      expect(fetchFileBlob).toHaveBeenCalledWith(
+        expect.objectContaining({
+          fileId: thumbnailInPersonalBucket.bucket_file,
+          bucketId: thumbnailInPersonalBucket.bucket_id,
+        }),
+        expect.objectContaining({
+          isWorkspace: false,
+        }),
+      );
+    });
+
+    test('When downloading thumbnail in personal context, then it uses personal credentials', async () => {
+      vi.mocked(localStorageService.getUser).mockReturnValue({ bucket: personalBucket } as any);
+
+      await downloadThumbnail(mockThumbnail, false);
+
+      expect(fetchFileBlob).toHaveBeenCalledWith(
+        expect.objectContaining({
+          fileId: mockThumbnail.bucket_file,
+          bucketId: mockThumbnail.bucket_id,
+        }),
+        expect.objectContaining({
+          isWorkspace: false,
+        }),
+      );
+    });
+  });
 });
diff --git a/src/app/drive/services/thumbnail.service.ts b/src/app/drive/services/thumbnail.service.ts
index 5002b21aa..273e28a42 100644
--- a/src/app/drive/services/thumbnail.service.ts
+++ b/src/app/drive/services/thumbnail.service.ts
@@ -1,5 +1,6 @@
 import { StorageTypes } from '@internxt/sdk/dist/drive';
 import { Thumbnail } from '@internxt/sdk/dist/drive/storage/types';
+import { UserSettings } from '@internxt/sdk/dist/shared/types/userSettings';
 import {
   thumbnailableExtension,
   thumbnailableImageExtension,
@@ -283,10 +284,21 @@ export const downloadThumbnail = async (thumbnailToDownload: Thumbnail, isWorksp
     return;
   };
   const abortController = new AbortController();
-  // TODO: CHECK WHY WITH THUMBNAILS NOT HAS TO USE WORKSPACE CREDENTIALS
+
+  let useWorkspaceCredentials = isWorkspace;
+
+  if (isWorkspace) {
+    const user = localStorageService.getUser() as UserSettings;
+    const isInPersonalBucket = thumbnailToDownload.bucket_id === user.bucket;
+
+    if (isInPersonalBucket) {
+      useWorkspaceCredentials = false;
+    }
+  }
+
   return await fetchFileBlob(
     { fileId: thumbnailToDownload.bucket_file, bucketId: thumbnailToDownload.bucket_id } as Downloadable,
-    { isWorkspace: false, updateProgressCallback, abortController },
+    { isWorkspace: useWorkspaceCredentials, updateProgressCallback, abortController },
   );
 };
 
diff --git a/src/app/network/UploadManager.test.ts b/src/app/network/UploadManager.test.ts
index 718b1fac4..97ae95fc2 100644
--- a/src/app/network/UploadManager.test.ts
+++ b/src/app/network/UploadManager.test.ts
@@ -558,4 +558,116 @@ describe('checkUploadFiles', () => {
       merge: { status: TaskStatus.Error, subtitle: expect.any(String) },
     });
   });
+
+  it('When uploading a file to a workspace, then it uses workspace credentials and same bucket for file and thumbnail', async () => {
+    const workspaceBucket = 'workspace-bucket-123';
+    const workspaceId = 'workspace-id-456';
+    const uploadFileSpy = (uploadFile as Mock).mockResolvedValueOnce(mockFile1);
+
+    vi.spyOn(tasksService, 'create').mockReturnValue('taskId');
+    vi.spyOn(tasksService, 'updateTask').mockReturnValue();
+    vi.spyOn(tasksService, 'addListener').mockReturnValue();
+    vi.spyOn(tasksService, 'removeListener').mockReturnValue();
+    vi.spyOn(errorService, 'castError').mockResolvedValue(new AppError('error'));
+
+    await uploadFileWithManager(
+      [
+        {
+          taskId: 'taskId',
+          filecontent: {
+            content: 'file-content' as unknown as File,
+            type: 'text/plain',
+            name: 'file.txt',
+            size: 1024,
+            parentFolderId: 'folder-1',
+          },
+          userEmail: 'user@test.com',
+          parentFolderId: '',
+        },
+      ],
+      openMaxSpaceOccupiedDialogMock,
+      DatabaseUploadRepository.getInstance(),
+      undefined,
+      {
+        ownerUserAuthenticationData: {
+          bucketId: workspaceBucket,
+          workspaceId: workspaceId,
+          bridgeUser: 'bridge-user',
+          bridgePass: 'bridge-pass',
+          encryptionKey: 'encryption-key',
+          token: 'token',
+          workspacesToken: 'workspaces-token',
+          resourcesToken: 'resources-token',
+        },
+        sharedItemData: {
+          isDeepFolder: false,
+          currentFolderId: 'parentFolderId',
+        },
+        isUploadedFromFolder: true,
+      },
+    );
+
+    expect(uploadFileSpy).toHaveBeenCalledWith(
+      'user@test.com',
+      expect.any(Object),
+      expect.any(Function),
+      expect.objectContaining({
+        isTeam: true,
+        ownerUserAuthenticationData: expect.objectContaining({
+          bucketId: workspaceBucket,
+          workspaceId: workspaceId,
+        }),
+      }),
+      expect.any(Object),
+    );
+  });
+
+  it('When uploading a personal file, then it uses personal credentials', async () => {
+    const uploadFileSpy = (uploadFile as Mock).mockResolvedValueOnce(mockFile1);
+
+    vi.spyOn(tasksService, 'create').mockReturnValue('taskId');
+    vi.spyOn(tasksService, 'updateTask').mockReturnValue();
+    vi.spyOn(tasksService, 'addListener').mockReturnValue();
+    vi.spyOn(tasksService, 'removeListener').mockReturnValue();
+    vi.spyOn(errorService, 'castError').mockResolvedValue(new AppError('error'));
+
+    await uploadFileWithManager(
+      [
+        {
+          taskId: 'taskId',
+          filecontent: {
+            content: 'file-content' as unknown as File,
+            type: 'text/plain',
+            name: 'file.txt',
+            size: 1024,
+            parentFolderId: 'folder-1',
+          },
+          userEmail: 'user@test.com',
+          parentFolderId: '',
+        },
+      ],
+      openMaxSpaceOccupiedDialogMock,
+      DatabaseUploadRepository.getInstance(),
+      undefined,
+      {
+        ownerUserAuthenticationData: undefined,
+        sharedItemData: {
+          isDeepFolder: false,
+          currentFolderId: 'parentFolderId',
+        },
+        isUploadedFromFolder: true,
+      },
+    );
+
+    expect(uploadFileSpy).toHaveBeenCalledWith(
+      'user@test.com',
+      expect.any(Object),
+      expect.any(Function),
+      expect.objectContaining({
+        isTeam: false,
+        ownerUserAuthenticationData: undefined,
+      }),
+      expect.any(Object),
+    );
+  });
 });
diff --git a/src/app/network/UploadManager.ts b/src/app/network/UploadManager.ts
index 1d842dc36..393aad37d 100644
--- a/src/app/network/UploadManager.ts
+++ b/src/app/network/UploadManager.ts
@@ -178,7 +178,7 @@ class UploadManager {
             }
           },
           {
-            isTeam: false,
+            isTeam: !!this.options?.ownerUserAuthenticationData?.workspaceId,
             abortController: this.abortController ?? fileData.abortController,
             ownerUserAuthenticationData: this.options?.ownerUserAuthenticationData,
             abortCallback: (abort?: () => void) => {