Slack Attachment Guide (2026)
Slack File Upload Limit & Workspace Quota Management
Slack allows individual file uploads up to 1 GB, but free workspaces have a tight 5 GB total storage limit. Once exceeded, older messages and files are hidden behind paywalls.
File too large for Slack?
Send up to 3 GB free with zero-knowledge browser encryption · No accounts, auto-purged links
Send file via LimeShare linkSlack limit breakdown
| Constraint | Details |
|---|---|
| Stated attachment limit | 1 GB per file |
| Encoding overhead | Files count permanently toward workspace storage limits |
| Cloud fallback behavior | Upload fails when workspace total storage is full |
| Recipient requirement | Requires Slack workspace membership |
| Privacy & scanning | Stored in plaintext for Slack administrators; subject to corporate retention |
Why files bounce on Slack
Uploading design prototypes, raw screen recordings, or database dumps quickly exhausts the shared workspace storage pool, forcing teams into paid Slack plans.
How to send files larger than 1 GB
- Share large files via LimeShare links inside your Slack channels.
- Your Slack storage quota remains at 0 MB because files live on zero-knowledge cloud storage.
- Client-side encryption ensures confidential internal documents remain unreadable to Slack or third-party app integrations.
Frequently asked questions
Do LimeShare links consume my Slack workspace storage?
No. Only the text link is posted in Slack. The file bytes stream directly from encrypted edge storage and self-destruct, saving your workspace storage quota.