Mattermost Professional alternatives: 5 free & open-source picks
Curated, verified, and actually free. No trials, no crippled tiers. Star counts and last-activity dates checked by hand, not scraped and forgotten.
Channels, threads, search and integrations for up to a hundred concurrent users; MongoDB joins the team.
licenseMIT
runsyour server
installDeploy the Community workspace with Docker Compose, Podman, or Kubernetes
dataUsers, rooms, messages, and most metadata live in MongoDB; uploads live on local storage or a configured object-storage backend.
the catch vs Mattermost ProfessionalRocket.Chat Community provides the expected team-chat surface, but MongoDB and upgrades are yours and the free Community workspace is limited to 100 concurrent users.
setupA production installation requires MongoDB, DNS/TLS, email, backups, upgrades, and enough capacity planning to stay within the Community plan's 100-concurrent-user limit.
facts verified 2026-08-10
Mattermost without the invoice: full team chat below 250 users, but no SSO and every server problem belongs to you.
licenseMIT
runsyour server
installInstall the official Linux binary with PostgreSQL, then configure systemd, TLS/reverse proxy, SMTP, and file storage
dataChannels, posts, users, and configuration live in PostgreSQL; file attachments live in the Mattermost data directory or configured S3-compatible object storage.
the catch vs Mattermost ProfessionalTeam Edition keeps the core chat product, but Professional features such as enterprise authentication, advanced compliance and administration, support, and larger-scale assurances are absent.
setupThe first obstacle is a real Linux service deployment, PostgreSQL, SMTP, DNS/TLS, storage, backups, and upgrades, not an app-store install.
facts verified 2026-08-10
Email-shaped topics inside team chat; excellent for async work and merciless about naming conversations.
Matrix rooms, threads, files and search with free hosted accounts; less Slack clone, more protocol.
licenseAGPL-3.0-or later OR GPL-3.0+
runsyour machine or their cloud
installUse a free Matrix account in Element Web/mobile/desktop, or deploy Element Server Suite on your own infrastructure
dataRooms, event history, account data, and media live on the selected Matrix homeserver; encrypted-room keys remain on clients and can be backed up through Matrix's key-backup system.
the catch vs Mattermost ProfessionalElement covers rooms, threads, files, and search, but its Matrix-first model and smaller workplace-integration surface are less familiar and less Slack-like than Mattermost.
setupThe clean hosted path is easy, but self-hosting the current Element Server Suite means operating a Matrix homeserver and its Kubernetes/Helm-based stack.
facts verified 2026-08-10
Unlimited users, channels and history with ten gigabytes total; group meetings and serious integrations still cost money.
licenseproprietary, free
runstheir cloud
installHosted signup; use the browser or Pumble's desktop/mobile apps
dataMessages, channels, user records, and files live in Pumble's cloud; workspace owners can export public-channel data as a ZIP with message data and file links.
the catch vs Mattermost ProfessionalPumble Free removes server work and keeps unlimited history, but free group meetings, screen sharing, broad integrations, storage, and self-hosted control fall short of Mattermost Professional.
setupThere is no installation hurdle, but migration still requires inviting everyone and rebuilding channels and integrations; free exports exclude private channels and direct messages.
facts verified 2026-08-10
last updated 2026-08-10 · no votes, no pay-to-list · just what's real
| tool | license | running it | platforms | stars | active |
|---|---|---|---|---|---|
| Rocket.Chat Community | MIT | self-host, real ops | web, macos, windows, linux, ios, android, self-hosted | 45,900 | 2026-08 |
| Mattermost Team Edition | MIT | self-host, real ops | web, macos, windows, linux, ios, android, self-hosted | 38,700 | 2026-08 |
| Zulip | open source | self-host, real ops | web, macos, windows, linux, ios, android, self-hosted | 25,600 | 2026-08 |
| Element | AGPL-3.0-or later OR GPL-3.0+ | they host it | web, macos, windows, linux, ios, android, self-hosted | 13,300 | 2026-07 |
| Pumble Free | proprietary, free | they host it | web, macos, windows, linux, ios, android | — | — |
People still pay for Mattermost Professional because community software is valuable when members are already there and the operator does not have to own realtime reliability and abuse response. The recurring cost buys realtime delivery, notifications, abuse handling, search, media, permissions, mobile clients, backups, and community operations, not just the visible interface. If none of that applies to you, any pick above saves $120 a year.
Is there a free alternative to Mattermost Professional?
Yes: Rocket.Chat Community, Mattermost Team Edition, Zulip and 2 more. Every tool on this page is either open source or genuinely free to use long-term: no trials, no crippled tiers.
Should I just build my own Mattermost Professional?
Our verdict is PARCIAL. The core loop is buildable, but a dependable replacement becomes a real weekend or multi-day project. For Mattermost Professional, self-host team chat with channels, threads, search, and integrations. The hard boundary is managed operations, mobile push, enterprise security, support, and governance, plus network, moderation, and communication infrastructure. If you'd rather build, the exact one-shot prompt is free at puedovibecodearlo.app/mattermost-professional.
