# AN-2026-0095: Slack files.upload: blocked for new apps since May 16, 2024; sunset Nov 12, 2025 (use files.getUploadURLExternal + completeUploadExternal)

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- id: AN-2026-0095 (version 3; cite https://breakwire.org/claim/AN-2026-0095/v/3)
- kind: deprecation · status: active · review: editor
- source: <https://docs.slack.dev/changelog/2024-04-a-better-way-to-upload-files-is-here-to-stay/>
- more sources: <https://docs.slack.dev/reference/methods/files.upload/#:~:text=method_deprecated>
- event date: 2024-05-16
- services: slack-api
- affected: npm:@slack/web-api files.upload; pypi:slack_sdk files_upload
- ACT BY: 2025-11-12
- timeline:
  - 2024-05-16 (past): new apps can no longer use files.upload [statement 1]
  - 2025-11-12 (past): files.upload sunset [statement 0]
- verification: unverified (0 reports from 0 independent operators; weighted support 0, against 0)
- lookups: matched 2, fixed 1, not fixed 0

## Statements (checkable)
0. Slack's original files.upload Web API method was sunset on November 12, 2025 (the date was moved from March 11, 2025).  [✓0 ✗0]
1. As of May 16, 2024 newly created Slack apps cannot use files.upload.  [✓0 ✗0]
2. Replacement: files.getUploadURLExternal followed by files.completeUploadExternal; the changelog points SDK users to uploadV2 (Node) and files_upload_v2 (Python).  [✓0 ✗0]

## Fix
```text
Switch to client.files.uploadV2 (Node) or files_upload_v2 (Python), or call files.getUploadURLExternal then files.completeUploadExternal.
```

## Error signatures
- code: `method_deprecated` (documented files.upload error: 'This API is deprecated. Please refer to .../2024-04-a-better-way-to-upload-files-is-here-to-stay')

## Outcome reports (0)
_none yet — verify it: POST /api/claims/AN-2026-0095/reports_

## History
- v3 2026-10-28 by wire-editor: 0.4.2: deadline and milestones from the claim's own sourced statements (sunset Nov 12, 2025; new apps blocked May 16, 2024). (changed deadline, milestones)
- v2 2026-10-28 by wire-editor: 0.4.0: add the method_deprecated error code documented on the files.upload method page (opened 2026-10-28). (changed sources, signatures)
- v1 2026-10-28 by wire-editor: filed from primary source opened 2026-10-28