Best Open Source Microsoft Teams Alternatives

Open-source chat solution offering real-time messaging, video calls, and file sharing for teams of all sizes.

Mattermost provides a flexible, open-source platform for secure team collaboration, designed for organizations with strict security and privacy requirements.

Nextcloud offers on-premises file sync, sharing and collaboration platform with advanced security and privacy features.

Host encrypted video conferences directly in your browser, deploy on your own servers, or integrate into applications - all with this powerful open source platform.

Zulip is an open-source team chat app that uses threaded conversations to keep communication organized and efficient for teams of all sizes.

Open-source platform for encrypted communication, file sharing, and collaboration based on the Matrix protocol.

Create customizable virtual workspaces for remote teams to interact naturally, host events, and collaborate through spontaneous conversations and scheduled meetings.

Open-source collaboration platform combining real-time chat, document editing, file sharing, and project management. Self-host for complete control.

Install your own group chat system with @mentions, DMs, and mobile support. One-time purchase, no monthly fees. Includes full source code for customization.

Cinny offers a simple, elegant, and secure interface for Matrix-based conversations, protected by end-to-end encryption.

A comprehensive collaboration platform offering end-to-end encrypted messaging, file sharing, and video calls with enterprise-grade security and compliance features.

Streamline team communication with shared inboxes, unlimited email addresses, and customizable workflows. Perfect for modern businesses seeking organized email management.

Build your own community space for gaming, chatting, and hanging out with friends worldwide. Customize your environment for the perfect social experience.

Open source chat server with end-to-end encryption, clustering support, and comprehensive messaging features for building real-time communication apps

Free Matrix-based messenger with end-to-end encryption, multi-platform bridges, and on-premise deployment. Connect across 30+ networks securely.