Mattermost is an open source, self hostable team messaging platform, a secure, private alternative to Slack, popular with technical, security conscious and regulated teams wanting control over their chat. It provides channel based team messaging, direct messages, file sharing, search, voice calls and integrations, delivered as open source software that organisations can self host on their own infrastructure (or use as cloud), giving full control over data, security and customisation. Popular with technical teams, developers, and security conscious or regulated organisations (including government and defence) that need a private, controllable, often self hosted Slack alternative, Mattermost combines familiar team chat with openness and control. For open source, self hosted messaging, Mattermost is a leading choice.
Mattermost's distinction is open source, self hostable team chat offering control, privacy and security. It delivers a familiar Slack like messaging experience that organisations can run on their own infrastructure, with full control over data and the ability to customise, which technical, security conscious and regulated teams need and that cloud only tools cannot offer. That openness, self hosting and control set it apart.
Mattermost is best for technical teams, developers, and security conscious or regulated organisations (including government, defence and finance) that want a private, controllable, often self hosted team chat with open source openness and control over data. It suits control and privacy focused teams. It is a weaker fit for teams wanting the most polished cloud chat and richest integrations, where Slack fits, Microsoft or Google organisations using bundled chat, or community and informal use, where Discord fits.
The core strengths are channel based team messaging, direct messages, file sharing, search, voice calls and integrations, delivered as open source software that can be self hosted for full control over data, security and customisation, or used as cloud. Mattermost offers developer and DevOps integrations, plugins, and compliance and security features. Its openness, self hosting, control and security are its defining advantages.
Mattermost offers a free, open source edition you can self host (paying only infrastructure), with paid Professional from around 10 US dollars per user a month and Enterprise quoted, adding advanced security, compliance and support, available self hosted or cloud. So teams can self host free or pay for enterprise features and support. Costs are infrastructure or per user for paid tiers. Confirm details via the Mattermost pricing page.
Mattermost integrates with developer and DevOps tools (GitHub, GitLab, Jira, CI/CD), plugins, and apps, with an API and open source extensibility, suited to technical teams. Its developer and DevOps integrations and open extensibility, which let technical teams tie chat into their workflows and customise it, support its technical and control focused positioning.
Open source, self hosted control is the signature strength: Mattermost delivers familiar team chat that organisations can run on their own infrastructure with full control over data, security and customisation, which technical, security conscious and regulated teams need and cloud only tools cannot offer. For such organisations, this control and openness are the main reason to choose Mattermost.
Mattermost is well rated for openness, self hosting, security and developer fit, with community and enterprise support, though self hosting takes technical effort and its experience is less polished than Slack. Its G2 reviews praise control, security and developer integrations, with self hosting effort and polish versus Slack the main considerations.
For technical, security conscious and regulated organisations that want private, controllable, often self hosted team chat with open source openness, Mattermost is an excellent choice. The main caution is self hosting effort and a less polished experience than Slack, so teams wanting the most polished cloud chat may prefer Slack, Microsoft or Google organisations their bundled chat, and community use Discord, but for open source, self hosted messaging Mattermost leads.
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