Flock vs Mattermost: Which is Better in 2026?
Choosing between Flock and Mattermost comes down to understanding what each tool does best. This comparison breaks down the key differences so you can make an informed decision based on your specific needs, not marketing claims.
Bottom line: Mattermost wins this matchup. Microsoft Teams is our overall Team Chat pick. Microsoft Teams is our free Team Chat pick. Pick Flock if you need team chat.
Short on time? Here's the quick answer
Based on published vendor pricing and features and on public review data, here's who should pick what:
Flock
Team messaging and collaboration platform
Best for you if:
- • You want simple team messaging
Mattermost
Open-source team collaboration platform
Best for you if:
- • You want open source Slack alternative
| At a Glance | Flock | Mattermost |
|---|---|---|
Starts at | Free Free plan | Free Free plan |
Category | Team Chat Communication | Communication Team Chat |
Rating | 4.5/5 Capterra 4.5 · G2 4.4 644 reviews | 4.3/5 G2 4.3 · Capterra 4.4 · SourceForge 4.3 604 reviews |
Free plan | Yes | Yes |
Watch out for | Guests free for only 90 days | n/a |
Choose Flock or Mattermost?
Choose Flock if
- You want simple team messaging
- You want video calls included
- You work in team chat, not communication
Choose Mattermost if
- You want open source Slack alternative
- You want self-hostable
- You work in communication, not team chat
In-Depth Analysis
Flock
Team messaging and collaboration platform
Flock's pricing structure is quite generous, especially with a robust free 'Starter' tier for small teams.
Watch out
Guests free for only 90 days
Strengths
- Pro: Simple team messaging
- Pro: Video calls included
- Pro: Affordable
- Pro: To-do integration
- Pro: Good for small teams
Weaknesses
- Con: Smaller user base
- Con: Limited integrations
- Con: Less features than Slack
- Con: Mobile apps okay
- Con: Less known
Key features
Mattermost
Open-source team collaboration platform
Mattermost's pricing is fair, offering a generous Free tier for small teams.
Strengths
- Pro: Open source Slack alternative
- Pro: Self-hostable
- Pro: Good for compliance
- Pro: No per-user cloud cost
- Pro: Customizable
Weaknesses
- Con: Less polished than Slack
- Con: Smaller integration library
- Con: Self-hosting required for best value
- Con: Learning curve
- Con: Community smaller
Key features
Pricing: Flock vs Mattermost
| Plan | Flock | Mattermost |
|---|---|---|
| Tier 1 | Free Starter | Free Free |
| Tier 2 | /user/month Pro | $10 Professional |
| Tier 3 | custom Enterprise | Custom Enterprise |
Pricing verified from each vendor's public pricing page. Compare in detail on Flock pricing and Mattermost pricing.
Key Takeaways
Mattermost
- Free tier available
- Our pick for this comparison
Flock
- Higher user rating: 4.5/5 vs 4.3/5
- Larger review base (644 reviews)
- Better fit for team chat
The Bottom Line
Mattermost wins this matchup. Microsoft Teams is our overall Team Chat pick. Microsoft Teams is our free Team Chat pick.
Frequently Asked Questions
Is Flock or Mattermost better in 2026?
Mattermost wins this matchup. Microsoft Teams is our overall Team Chat pick. Microsoft Teams is our free Team Chat pick. Pick Flock for team chat workflows (main strength: simple team messaging). Pick Mattermost for communication workflows (main strength: open source Slack alternative).
What are Flock and Mattermost used for?
Flock: Team messaging and collaboration platform. Mattermost: Open-source team collaboration platform.
What does Flock cost vs Mattermost?
Flock pricing is on their site. Mattermost's paid plans start at Free (Professional).
What's the main difference between Flock and Mattermost?
Flock's main strength: simple team messaging. Mattermost's main strength: open source Slack alternative.