Element vs Mattermost

Comparing two open source alternatives to Discord and Slack. Use the comparison below to decide which one fits your needs.

Element

AGPL-3.0

Open-source Matrix client for secure, decentralized messaging, voice, and video — runs on your own server.

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Mattermost

Mattermost is an open source platform for secure collaboration across the entire software development lifecycle..

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Side-by-side comparison

	Element	Mattermost
License	AGPL-3.0	—
Self-hostable	Yes	No
GitHub Stars	13,552	39,306
Forks	2,785	9,043
Open Issues	3,716	1,087
Last Commit	Oct 10, 2026	Oct 10, 2026
First Released	Jul 22, 2015	Jun 15, 2015
Categories	Team Chat & Messaging Tools	Team Chat & Messaging Tools
Tags	#chat #messaging #privacy #self hosted #voice chat	—

GitHub stars over time

Element13,552

Mattermost

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