Open-source alternatives to Slack
Self-host a Slack alternative from $4.13/mo and save up to $34/yr per seat vs Slack. 10 open-source projects that replace Slack, ranked by computed health score and real self-hosting cost.
Why people leave Slack
- Free tier hides messages older than 90 days
- Per-seat pricing ($7-15/user/mo) gets expensive past 20 people
- No self-hosting option even on Enterprise Grid
- Storage is capped per workspace
Mattermost, Rocket.Chat, and Zulip give the same channels, threads, and integrations on your infra with full message history forever.
The 10 alternatives, ranked by health
Health score is a 6-dimension composite. See methodology for formula and weights.
Zulip server and web application. Open-source team chat that helps teams stay productive and focused.
The Secure CommsOS™ for mission-critical operations
The easy-to-use open source Business Intelligence and Embedded Analytics tool that lets everyone work with data
Slack API in Go
Lightweight library for web server applications in Swift on macOS and Linux powered by coroutines.
Automated developer-oriented status page with alerting and incident support
All new design. Inspect your iOS application at runtime.
Open-source and local-first Slack and Notion alternative that puts you in control of your data
Monitor your Website and APIs from your Computer. Get Notified through Slack, E-mail when your server is down or response time is more than expected.
A community discussion platform: Brings together the main features from StackOverflow, Slack, Discourse, Reddit, and Disqus blog comments.
Compare the top Slack alternatives head-to-head
Side-by-side breakdowns and self-hosting cost for the leading picks.
Cost comparison vs Slack
Self-hosting cost on cheapest plan meeting requirements vs Slack entry tier ($7/mo).
| Project | Self-host /mo | Slack /mo | Save /yr | |
|---|---|---|---|---|
| zulip | $4.13 | $7+ | $34 | Deploy → |
| Rocket.Chat | $4.13 | $7+ | $34 | Deploy → |
| metabase | $4.13 | $7+ | $34 | Deploy → |
| slack | $4.13 | $7+ | $34 | Deploy → |
| Zewo | $4.13 | $7+ | $34 | Deploy → |
| gatus | $4.13 | $7+ | $34 | Deploy → |
| Peek | $4.13 | $7+ | $34 | Deploy → |
| colanode | $4.13 | $7+ | $34 | Deploy → |
Pick your alternative
Most operators land on zulip (top health score in this category; cheapest VPS path is zulip on hetzner for $4.13/mo).
Data refreshed daily. Pricing for Slack sourced from official site.