Mattermost review 2026: the open-source Slack alternative for secure, self-hosted team messaging. Compare pricing, features, pros, cons and alternatives.
Category
Team Chat
Pricing
Freemium, from Free (Starter, self-hosted); Professional from $10/user/month
Mattermost is an open-source alternative to Slack and Microsoft Teams, built for organizations that need full control over where their communication data lives, whether that is a self-hosted server, an air-gapped environment, or Mattermost's managed cloud.
Founded in 2011 by Corey Hulen and Ian Tien and headquartered in Palo Alto, California, Mattermost has built a strong following among software engineering teams, DevOps organizations and government or regulated-industry customers who need secure, self-hostable messaging.
Key Features
Core messaging features include channels, direct and group messages, voice calls and screen sharing, alongside deep integrations with developer tools like GitHub, GitLab, Jenkins, Jira and ServiceNow via webhooks, slash commands and bots.
Playbooks, Mattermost's workflow automation feature, lets teams build repeatable, checklist-driven processes for incident response, security operations or onboarding, automatically spinning up a dedicated channel with tasks and status tracking when triggered.
Pricing
The free Starter tier is self-hosted with unlimited users, channels and message history, making it a capable entry point for small teams or evaluation.
Professional costs 10 dollars per user per month billed annually and adds SSO, LDAP sync, MFA and guest accounts, while Enterprise is custom-priced and adds high-availability clustering, compliance exports and 24x7 support, available either self-hosted or via Mattermost Cloud.
Key Features
Channel-based messaging — Organize conversations into public, private and direct-message channels, similar to Slack.
Playbooks workflow automation — Build repeatable, checklist-driven processes for incident response, onboarding or other multi-step workflows.
Self-hosted and air-gapped deployment — Runs as a single Go binary with PostgreSQL, supporting fully on-premise or air-gapped installations.
Voice calls and screen sharing — Built-in calling and screen-share tools reduce the need for separate video conferencing apps.
Developer tool integrations — Native integrations with GitHub, GitLab, Jenkins, Jira and ServiceNow plus custom webhooks and bots.
SSO and directory sync — Professional and Enterprise tiers support SAML/OAuth SSO and Active Directory/LDAP synchronization.
Compliance exports and audit logging — Enterprise tier adds compliance-grade message export and advanced administrative controls.
High-availability clustering — Enterprise deployments can scale across clustered nodes for reliability at large organizations.
Pros & Cons
Pros
Fully open-source core with self-hosted and air-gapped deployment options
Strong fit for regulated industries, government and defense customers
Playbooks provide built-in workflow automation not native to Slack
Deep integrations with developer and DevOps tooling
Lightweight architecture (single Go binary) makes self-hosting comparatively simple
Cons
Smaller app/integration marketplace than Slack or Microsoft Teams
Enterprise pricing is custom-quoted and not publicly transparent
Self-hosting requires ongoing server maintenance and updates
UI and mobile experience is generally considered less polished than Slack
Annual prepaid billing only for official Professional and Enterprise licenses, no monthly option
Pricing
Starter Free N/A
Professional $10/user/month annual
Enterprise Custom annual
Frequently Asked Questions
Is Mattermost free
Yes, the Starter tier is free and self-hosted with unlimited users, channels and message history. Paid Professional and Enterprise tiers add security, compliance and support features.
Can Mattermost be self-hosted
Yes, Mattermost can be fully self-hosted, including in air-gapped environments, or run through Mattermost Cloud as a managed service.
How much does Mattermost Professional cost
Professional costs 10 dollars per user per month, billed annually.
What is Mattermost Playbooks
Playbooks is a workflow automation feature for building repeatable, checklist-driven processes like incident response or onboarding, integrated directly with channels.
Who uses Mattermost
Mattermost is popular with software engineering and DevOps teams, as well as government, defense and financial-services organizations that need self-hosted or compliant messaging.
How does Mattermost compare to Slack
Mattermost offers similar core messaging features to Slack but adds open-source self-hosting, air-gapped deployment and built-in workflow automation, targeting security- and compliance-sensitive organizations.