Slack vs Mattermost
Slack is team messaging platform with channels, threads, and integrations for workplace communication, while Mattermost is open-source, self-hosted team messaging platform for organizations that need data sovereignty. The biggest difference up front: Mattermost is free, while Slack starts at $7.25/user/mo. Slack is built for teams that need organized, searchable communication, whereas Mattermost targets teams that need self-hosted, privacy-first messaging.
Free
| Feature | Slack | Mattermost |
|---|---|---|
| Free tier available | ✓ | ✓ |
| Open source | — | ✓ |
| Channels | ✓ | ✓ |
| Compliance | — | ✓ |
| File Sharing | ✓ | — |
| Huddles | ✓ | — |
| Integrations | ✓ | ✓ |
| Playbooks | — | ✓ |
| Self-Hosted | — | ✓ |
| Threads | ✓ | — |
Pricing: Mattermost is completely free, which makes it the obvious pick if budget is the top concern. Slack starts at $7.25/user/mo, but Free for small teams, 90-day history. That cost buys you a more polished or feature-rich experience, so it comes down to whether the extras justify the spend.
Feature gaps: Slack offers File Sharing, Huddles and Threads that Mattermost lacks. Mattermost brings Compliance, Playbooks and Self-Hosted that Slack does not have. Both share Channels and Integrations.
Team fit: Slack is geared toward any size teams, while Mattermost is aimed at mid-size teams teams. Pick the one that matches where your team is today and where it is headed — migrating tools later is always painful.
Open source: Mattermost is open source, meaning you can self-host, audit the code, and avoid vendor lock-in. Slack is proprietary — you are trusting the vendor with your data and uptime.
Where each tool shines: Slack's biggest strengths are: massive integration ecosystem with 2,400+ apps. excellent search across all messages and files. Mattermost's biggest strengths are: self-hosted — full control over your data. open source with active community.
Watch out for: With Slack, users commonly note that expensive at scale — costs add up fast with large teams. With Mattermost, the main complaint is that requires server management if self-hosting.
choose Slack if
- Your profile matches its sweet spot: teams that need organized, searchable communication
- You specifically need File Sharing and Huddles
- You care about excellent search across all messages and files
- Your team size fits the any size profile Slack is designed for
- The free tier works for you: free for small teams, 90-day history
choose Mattermost if
- Your profile matches its sweet spot: teams that need self-hosted, privacy-first messaging
- Budget is a hard constraint — Mattermost is free, Slack is not
- You need self-hosting, data sovereignty, or the ability to audit source code
- You specifically need Compliance and Playbooks
- You care about open source with active community
frequently asked
What is the difference between Slack and Mattermost?
Slack is team messaging platform with channels, threads, and integrations for workplace communication, while Mattermost is open-source, self-hosted team messaging platform for organizations that need data sovereignty. The biggest difference up front: Mattermost is free, while Slack starts at $7.25/user/mo. Slack is built for teams that need organized, searchable communication, whereas Mattermost targets teams that need self-hosted, privacy-first messaging.
Should I use Slack or Mattermost?
Mattermost is the free option; Slack charges $7.25/user/mo but may offer more polish. Here is how they compare.
When should I choose Slack over Mattermost?
Choose Slack if Your profile matches its sweet spot: teams that need organized, searchable communication; You specifically need File Sharing and Huddles; You care about excellent search across all messages and files; Your team size fits the any size profile Slack is designed for; The free tier works for you: free for small teams, 90-day history.
When should I choose Mattermost over Slack?
Choose Mattermost if Your profile matches its sweet spot: teams that need self-hosted, privacy-first messaging; Budget is a hard constraint — Mattermost is free, Slack is not; You need self-hosting, data sovereignty, or the ability to audit source code; You specifically need Compliance and Playbooks; You care about open source with active community.
related comparisons
Slack vs Microsoft Teams · Slack vs Discord · Slack vs Rocket.Chat · Slack vs Element · Slack vs Google Chat · Slack vs Lark · Slack vs Twist · Slack vs Pumble