Category: Collaboration

8 European alternatives to Mattermost — GDPR-compliant & EU-hosted.

Open-source messaging platform for developer and DevOps teams

Visit website ↗Assessment

Facts

Headquarters: US (US)
Category: Collaboration
Type: Product
GDPR-compliant: Yes
Open-source: Yes
Data hosting: US, EU

Top EU-based & GDPR-compliant alternatives to Mattermost

BigBlueButton (self-host)
Virtual classroom and video conferencing; self-hostable
EU · open-source
↗
CryptPad
End-to-end encrypted collaboration (FR/EU).
FR · open-source
↗
FluffyChat
Open-source Matrix chat client with focus on simplicity and privacy
DE · open-source
↗
HedgeDoc
Markdown collaboration; self-host.
DE · open-source
↗
Huly
Open-source project management and team collaboration platform (self-hosted only — vendor-hosted cloud service shut down in 2026 due to funding; huly.io hosted service discontinued)
PT · open-source
↗
HumHub
German open-source social intranet and collaboration platform
DE · open-source
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Kopano
Kopano Cloud is the proprietary successor to Kopano Groupware, which reached end-of-life on March 31, 2025. The open-source Kopano Groupware (AGPL) is no longer maintained; Kopano Cloud is available under a commercial/proprietary license only.
NL · commercial
↗
Nextcloud
Open-source self-hosted collaboration platform for file sync, chat, and office
DE · open-source
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Frequently asked questions

What is the best European alternative to Mattermost?

It depends on your use case. Strong EU alternatives to Mattermost include BigBlueButton (self-host), CryptPad and FluffyChat. On this page you can compare 8 EU alternatives by jurisdiction, data residency and open-source status.

Are there open-source alternatives to Mattermost?

Yes. Open-source EU alternatives to Mattermost include BigBlueButton (self-host), CryptPad, FluffyChat, HedgeDoc, Huly, HumHub and Nextcloud. These keep your data fully under your own control and let you self-host if you want to.

Is Mattermost GDPR-compliant and where is the data hosted?

Mattermost is headquartered in US and hosts data in US, EU. The vendor states it is GDPR-compliant, but the data falls under non-EU jurisdiction. For full EU data residency the EU alternatives on this page usually offer more certainty.

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