The best open source alternative to SAMA is Mattermost. If that doesn't suit you, we've compiled a ranked list of other open source SAMA alternatives to help you find a suitable replacement. Other interesting open source alternatives to SAMA are: Element, Fluxer, Cinny, and Stoat.
SAMA alternatives are mainly Team Chat & Messaging Tools but may also be Encrypted Communication Tools or Collaborative Workspaces. Browse these if you want a narrower list of alternatives or looking for a specific functionality of SAMA.
Mattermost provides a flexible, open-source platform for secure team collaboration, designed for organizations with strict security and privacy requirements.

Mattermost is an open-source collaboration platform built for organizations that require high levels of privacy, security and control over their communications. Some key features and benefits include:
Mattermost is designed for industries like defense, government, financial services, and critical infrastructure that have stringent requirements around data sovereignty and security. It provides a self-hosted alternative to cloud-based tools, giving organizations complete control over their collaboration environment.
The platform aims to improve team productivity and accelerate mission-critical work by providing a centralized hub for communication, process management, and integrations. With its focus on security and flexibility, Mattermost enables organizations to collaborate effectively even in highly regulated or air-gapped environments.
Looking for open source alternatives to other popular services? Check out other posts in the alternatives series and openalternative.co, a directory of open source software with filters for tags and alternatives for easy browsing and discovery.
Open-source platform for encrypted communication, file sharing, and collaboration based on the Matrix protocol.

Element is a powerful, open-source communication platform that puts privacy and security at the forefront. Built on the decentralized Matrix protocol, Element offers a comprehensive suite of features for both personal and professional use.
Key benefits of Element include:
Whether you're an individual seeking secure messaging or an organization looking for a flexible, scalable communication solution, Element provides the tools you need to stay connected while maintaining control over your data and privacy.
Free, open-source instant messaging and VoIP platform with full Markdown support, voice/video calls, moderation tools, and self-hosting options for communities.

Fluxer is a comprehensive communication platform that prioritizes user privacy and community building. This free and open-source messaging app offers everything you need to connect with friends, organize groups, and build thriving communities.
Core Features:
Customization & Control:
Built for Privacy: Made in Sweden with a focus on transparency, Fluxer is fully open source under AGPLv3 license. The platform supports responsible disclosure through their security bug bounty program and maintains active community involvement through their beta program.
Perfect for individuals seeking Discord alternatives, communities wanting data sovereignty, or organizations requiring secure, customizable communication solutions.
Cinny offers a simple, elegant, and secure interface for Matrix-based conversations, protected by end-to-end encryption.

Cinny is an open-source Matrix client that provides a secure and elegant interface for seamless conversations. Built on the Matrix protocol, it offers:
Cinny is constantly evolving to create a better communication experience. As an open-source project, it benefits from community contributions and transparency.
Key features:
Whether you're looking for a secure messaging solution for personal use or team collaboration, Cinny offers a refreshing alternative to traditional chat applications. Experience the power of open-source, decentralized communication with Cinny's user-friendly approach to Matrix.
Self-hostable group chat with servers, channels, voice, and moderation tools. No ads, no data mining, built under EU privacy law.

Stoat (formerly Revolt) is a group chat app built for friends and communities who want the features of mainstream platforms without the surveillance business model behind them. It's a direct Discord alternative that covers the basics well: servers, channels, voice chat, file sharing, and markdown support, all without ads or data collection.
Built in Europe under EU data protection law, the codebase is public and the privacy policy is short enough to actually read. There's no investor pressure shaping product decisions, which means features exist because users want them, not because they serve an ad-targeting pipeline.
A few things stand out from the typical chat app:
Compared to tools like Rocket.Chat or Twake Chat, Stoat leans toward the consumer end: it's designed to feel familiar to anyone coming from mainstream chat apps, with a lighter footprint and fewer enterprise-focused features. The 20MB file upload limit and server-specific profile pictures are available without paying, which removes friction that similar platforms put behind paywalls.
The issue tracker is public and the team runs a community server, so feedback has a direct path to the people building it.
A comprehensive collaboration platform offering end-to-end encrypted messaging, file sharing, and video calls with enterprise-grade security and compliance features.

Wire delivers military-grade security without sacrificing user experience. The platform features always-on end-to-end encryption for messages, files, and calls, while maintaining an intuitive interface for seamless team collaboration.
Key capabilities include:
Trusted by industry leaders including BMW, ExxonMobil, and government organizations worldwide, Wire ensures your sensitive communications remain private and compliant. The platform is particularly valuable for organizations requiring: