Social / platform API
Slack files.upload API method
Removed API method with an official replacement upload flow.
Current state
Sunset completed
Current Slack developer documentation states that files.upload stopped functioning and was officially sunset on November 12, 2025.
- Provider
- Slack
- Removal effective
- 2025-11-12
- Replacement
- files.getUploadURLExternal + files.completeUploadExternal
- Last checked
- 2026-08-20
Timeline
Lifecycle events
- 2024-04-09Slack announced files.upload retirement and the replacement upload flow.
- 2024-05-16Newly created apps could no longer use files.upload.
- 2025-11-12files.upload was sunset and became unavailable.
Evidence
Official sources
files.upload method — Slack Developer Docs
files.upload retirement changelog — Slack Developer Docs
Always verify with official provider documentation before making production changes.