Short answer: Mattermost is popular but controlled from outside the EU. If you want collaboration with data under European jurisdiction, 5 reviewed alternatives are listed below (1 Swedish), ranked by our score, not by who pays us.
Open-source team chat that can run entirely on your own servers in the EU. The cloud service is however in the USA (AWS us-east-1), the company is American (Palo Alto) and self-hosting requires technical skills.
Open source, can be self-hosted freely with full data control
EU data storage possible via self-hosting or managed partner
Cloud service stores data in the USA (AWS us-east-1), American parent company with CLOUD Act risk
Best for: Technically skilled teams that want to self-host a Slack-like chat on their own EU servers.
Swedish team chat with channels, direct messages as well as voice and video calls, running on Webbfabriken's own servers in Stockholm. Drawback: small vendor and a young service without a large ecosystem of integrations.
All data is stored in Stockholm, built and run by a Swedish company
Free for now, with core features such as channels, video and file sharing
Small vendor: long-term future and pricing model unclear (free now, paid tiers may come)
Best for: Small Swedish teams that want all chat data to stay in Sweden without American cloud.
EU/EEACollaborationFreemiumEU data storage ✓ISO 27001
End-to-end encrypted messaging and collaboration app with servers in Germany and Ireland. Drawback: the company is based in Switzerland (outside the EU/EEA) and the service is more messaging than full collaboration tool.
Strong end-to-end encryption for everything including calls
Data stored in the EU (Germany/Ireland), GDPR- and ISO 27001-aligned
The company is headquartered in Switzerland, i.e. outside the EU/EEA
Best for: Security-conscious teams that prioritize strong encryption for messages and calls.
EU/EEACustomer serviceFrom approx 220 SEK/monthEU data storage ✓
AI-driven cloud PBX and call-center platform for sales and support teams. Offers virtual numbers in 160+ countries, parallel/power dialer, call analytics, IVR and CRM integrations. Slovakian provider with EU storage.
AI voice agents, summaries and sentiment analysis
Parallel dialer, power dialer and call analytics
More expensive and complex than a simple cloud PBX for micro businesses
Best for: Sales teams and customer support with 2+ active employees who make a lot of calls and want advanced routing, dialer and call analytics.
EU/EEACollaborationFrom approx 99 SEK/monthEU data storage ✓ISO 27001
German all-in-one platform with team chat, task and project management, and video meetings; all data in German data centers. Drawback: entirely German/English interface with no Swedish language support.
All data stored exclusively in Germany, ISO 27001 certified
End-to-end encryption of messages, files, and tasks
No Swedish language support; interface is in German/English
Best for: EU-focused small businesses that want to combine chat and project management with high data security.
Export channels and history if possible, set up the new tool in parallel for two weeks, and move team by team instead of all at once.
Remember: the Data Act gives you a legal right to get your data out and switch cloud services, with a maximum 2-month notice period.
Common questions
Why switch from Mattermost?
Mattermost is controlled from a country outside the EU. For non-sensitive use this is rarely a problem, but for customer data, personal data or the public sector a Swedish or European vendor means simpler GDPR work and no CLOUD Act exposure through ownership.
Are there Swedish alternatives to Mattermost?
Yes, 1 of the alternatives below are Swedish. The rest are EU/EEA-based.
Are the alternatives as good?
It depends on your needs. We rank them by our overall score below. Some match Mattermost feature for feature, others trade depth for data sovereignty. Read each review.
Ratings and labels are based on our verified data, see How we review. Some links are affiliate links; that never affects ranking.
