| Feature | Limit |
|---|---|
| Chats and messaging | |
| Maximum characters in a single chat message | 4000 |
| Maximum file size |
1 GB Admins can restrict the maximum file size, up to 1024 MB (1 GB). |
| Maximum video size |
30 MB You can send larger videos as files. |
| Maximum number of file attachments in a single chat message (including GIFs) | 10 |
| Maximum number of scheduled or draft messages (combined limit) | 300 |
| Channels | |
| Maximum length of channel name | 256 characters |
| Maximum number of channels in an account (public and private) | Unlimited |
| Maximum number of default channels in an account | 5 |
| Maximum number of announcement channels in an account | 1 |
| Maximum number of channel owners (public and private) | 1 |
| Maximum number of channel admins (public and private) | 50 |
| Maximum number of members permitted to send messages in an announcement channel | 50 |
| Number of tabs in a channel | 10 |
| Channel members and groups | |
| Maximum number of members in a private channel | 250,000 (regional limitations may apply) 1 |
| Maximum number of members in a public channel | 250,000 (regional limitations may apply) 1 |
| Maximum number of members in a default channel | 250,000 |
|
Maximum number of members in an announcement channel |
Unlimited. Everyone in your organization’s account is added to default channels. |
| Maximum number of user groups in a channel | 10 |
| Maximum number of mention groups in a channel | 20 |
| Maximum number of members in a mention group | 100 |
| Maximum number of members in a channel to schedule or host a channel meeting | 1000 |
| Number of members that can be added to a channel at one time | 500 |
| Number of users’ emails that can be copied and pasted when adding to a channel | 100 |
| Storage and retention | |
| Maximum cloud storage retention | 10 years |
| Minimum cloud storage retention | 1 day (0 days if cloud storage disabled) 2 |
| Maximum local storage retention | None, you can save messages locally in perpetuity until local storage is met. |
| Maximum storage of sent messages shown on the Sent messages tab | Follows retention policies 3 |
| Chat organization | |
| Maximum number of folders per user | 200 |
| Maximum number of contacts, chats, and/or apps allowed in a folder | 100 |
| Maximum number of contacts, chats, and/or apps allowed in the Starred section | Unlimited |
| Maximum number of reminders | 100 |