Best Open-Source Microsoft Teams Alternatives (2026)

7 self-hostable, open-source projects that replace Microsoft Teams — without Microsoft 365 lock-in. Each is scored for how hard it is to self-host, with one-click deploy options where they exist.

Teams' real cost is Microsoft 365 lock-in: it is bundled to push you deeper into the Microsoft ecosystem, and your chat and meeting data lives in their cloud under their controls. Self-hosting decouples team communication from a 365 subscription and keeps the data on infrastructure you own.

Our picks at a glance

Easiest to self-host

Rocket.Chat

Difficulty 3/5 with a One-Click deploy path and built-in chat plus voice/video, the lowest-friction all-in-one here.

Most powerful

Rocket.Chat

The most feature-complete platform on this list, covering chat, calls and integrations in one server.

Most active

Rocket.Chat

At ~45k stars it has the strongest momentum of these options.

Best managed option

Rocket.Chat

Managed:yes with an official cloud offering, the cleanest managed path among the all-in-one choices.

Compare all 7 alternatives

Tap a column header to sort

Project			Deploy	License
Rocket.Chat TypeScript	45k ★	3/5 Moderate	One-Click Docker +3	MIT	6 days ago	Repo
Mattermost Go	33k ★	3/5 Moderate	One-Click Docker +3	MIT	7 days ago	Repo
Jitsi Meet TypeScript	24k ★	4/5 Involved	Docker Docker Compose +1	Apache-2.0	7 days ago	Repo
Zulip Python	23k ★	3/5 Moderate	Docker Compose Manual	Apache-2.0	6 days ago	Repo
Element (Web) TypeScript	12k ★	4/5 Involved	Docker Manual	AGPL-3.0	6 days ago	Repo
Synapse (Matrix Homeserver) Python	5k ★	4/5 Involved	Docker Docker Compose +2	AGPL-3.0	6 days ago	Repo
Nextcloud Talk JavaScript	2.1k ★	3/5 Moderate	Docker Docker Compose +1	AGPL-3.0	6 days ago	Repo

What to look for: Decide whether you need chat plus video in one product or are happy to pair a chat server with a dedicated meetings tool, since that shapes the choice. Check SSO, mobile and desktop clients, and the operational weight, as several strong options here are difficulty 4/5.

Head-to-head:Rocket.Chat vs Microsoft Teams Mattermost vs Microsoft Teams Jitsi Meet vs Microsoft Teams Zulip vs Microsoft Teams Element (Web) vs Microsoft Teams

The alternatives, reviewed

#1
Rocket.Chat
Self-host: Moderate
Fully customizable open-source communications platform and Slack alternative
45k TypeScript MIT 6 days ago
How it compares to Microsoft Teams
Resource-heavy (Node.js + MongoDB) and can be slow at scale on modest hardware

Some enterprise features (engagement dashboard, scalability, advanced auth) require a paid plan

UI can feel cluttered compared to Slack

Mobile apps have historically lagged the web client in polish
Repo Details & deploy →
#2
Mattermost
Self-host: Moderate
Open-source, self-hostable Slack alternative for secure team messaging and collaboration
33k Go MIT 7 days ago
How it compares to Microsoft Teams
Many advanced features (LDAP/AD, SAML/SSO, compliance exports, high availability) are gated behind paid Enterprise tiers

Search and message UX feel less polished than Slack

Voice/video calling is more limited than Teams' full meetings stack

Smaller third-party app/integration marketplace than Slack
Repo Details & deploy →
#3
Jitsi Meet
Self-host: Involved
Self-hostable open-source video conferencing alternative to Teams meetings
24k TypeScript Apache-2.0 7 days ago
How it compares to Microsoft Teams
Primarily video meetings; it is not a persistent team-chat workspace with channels

Self-hosting the full stack (Jicofo, JVB, Prosody, TURN) for scale is non-trivial

Large meetings require careful videobridge tuning and bandwidth provisioning

Lacks the broader collaboration suite (files, tabs, apps) of Microsoft Teams
Repo Details & deploy →
#4
Zulip
Self-host: Moderate
Open-source team chat with a unique topic-based threading model
23k Python Apache-2.0 6 days ago
How it compares to Microsoft Teams
Native voice/video calling is limited and usually relies on third-party integrations (Jitsi, Zoom)

The topic-threading model has a learning curve and can feel unfamiliar to Slack users

Production installs effectively want a dedicated server; multi-host scaling is involved

Smaller app/integration ecosystem than Slack
Repo Details & deploy →
#5
Element (Web)
Self-host: Involved
Matrix-based secure messenger and Slack alternative with end-to-end encryption
12k TypeScript AGPL-3.0 6 days ago
How it compares to Microsoft Teams
Requires running and maintaining a separate Matrix homeserver (e.g. Synapse) for a full deployment

End-to-end encryption key management and device verification can confuse non-technical users

Performance and load times lag native Slack/Teams clients in large rooms

Threads and search are less refined than Slack
Repo Details & deploy →
#6
Synapse (Matrix Homeserver)
Self-host: Involved
Reference Matrix homeserver powering decentralized, federated team chat
5k Python AGPL-3.0 6 days ago
How it compares to Microsoft Teams
It is a backend only; you must pair it with a client (Element) for a usable product

Federation and database (PostgreSQL) tuning is required for scale and can be resource-intensive

Setup involves reverse proxy, TLS, well-known config, and federation ports

AGPL license and commercial relicensing have caused community friction
Repo Details & deploy →
#7
Nextcloud Talk
Self-host: Moderate
Self-hosted chat, video calls, and conferencing integrated into Nextcloud
2.1k JavaScript AGPL-3.0 6 days ago
How it compares to Microsoft Teams
Requires a running Nextcloud installation as a prerequisite

Larger group video calls need a separate High Performance Backend (Janus/signaling server) to scale

Chat features are less rich than dedicated platforms like Slack

Fewer third-party app integrations focused on messaging
Repo Details & deploy →

The verdict

Rocket.Chat is the best single-product Teams replacement for chat plus meetings; if you want best-in-class video conferencing, pair a chat server with Jitsi Meet, or choose Element on Matrix when end-to-end encryption and federation are priorities.

Still deciding? Compare Rocket.Chat vs Mattermost side by side →

Microsoft Teams alternatives — frequently asked questions

What is the best open-source alternative to Microsoft Teams?

Rocket.Chat is the strongest all-in-one pick, combining persistent chat with voice and video in a single self-hostable platform. For meetings specifically, Jitsi Meet is the leading open-source video conferencing tool.

Which Teams alternative is easiest to self-host?

Rocket.Chat, Mattermost and Zulip are all difficulty 3/5, with Rocket.Chat and Mattermost offering One-Click deployment. Jitsi Meet, Element and Synapse are heavier at difficulty 4/5.

What is the best open-source replacement for Teams video meetings?

Jitsi Meet is purpose-built for this: self-hostable, Apache-2.0 video conferencing that directly replaces Teams meetings. Many teams run it alongside a chat server like Rocket.Chat or Mattermost.

Is there a free self-hosted Teams alternative without Microsoft 365?

Yes. Rocket.Chat (MIT), Mattermost (MIT), Zulip (Apache-2.0) and Jitsi Meet (Apache-2.0) are all free, open source, and run entirely independent of Microsoft 365, removing the lock-in.

Which alternative offers end-to-end encryption and federation?

Element (Web), backed by a Synapse homeserver, runs on Matrix and provides end-to-end encrypted, federated messaging. This is the privacy-first choice, at difficulty 4/5 to self-host.

Can I host Teams-style chat without running my own server?

Rocket.Chat, Mattermost, Jitsi Meet, Zulip, Element and Synapse all offer managed hosting (managed:yes). Nextcloud Talk is self-host-only but integrates chat and video into an existing Nextcloud instance.

Keep exploring

All Team Chat & Collaboration →Self-hosted directory →Easiest to self-host →

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