Category: Email (Personal)
8 European alternatives to Caliopen — GDPR-compliant & EU-hosted.
Open-source unified secure messaging platform combining email and encrypted messaging, relocated from France to Luxembourg to avoid French surveillance law.
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Facts
- Headquarters
- LU (EU)
- Sovereignty model
- Open-source, distributed
- Category
- Email (Personal)
- Type
- Product
- GDPR-compliant
- Yes
- Open-source
- Yes
- Data hosting
- EU
Sources
Public sources used in the latest check of this record.
Compliance evidence
The links below point to the vendor's own public documents. We only record what we found: a missing link means "not found publicly", not "not compliant".
No public compliance evidence has been recorded for this vendor yet. Do you know its DPA or subprocessor list? Something wrong? Suggest a correction
Sovereignty profile of Caliopen
How this vendor scores on the five dimensions of the Digital Sovereignty Heatmap: 0 is sovereign, 100 is high exposure. These are the same scores the assessment uses.
| Jurisdictional exposure (JES) | Headquartered in the EU: European law applies | 0 |
|---|---|---|
| Data residency (DRS) | EU-only hosting | 0 |
| Cryptographic key sovereignty (CKS) | Self-hostable: encryption keys under your own control | 10 |
| Platform lock-in (PLS) | Open source: low switching costs | 20 |
| Source & runtime sovereignty (SRS) | Source code auditable, forkable and self-hostable | 0 |
| Average | 6 |
Why digital sovereignty matters with Caliopen
Caliopen is headquartered in LU and therefore falls under European law: the GDPR, NIS2 and the Data Act. No foreign legislation can compel access to your data.
Data is hosted exclusively in the EU, so Caliopen scores best on data residency.
Caliopen is open source. You can audit the source code, self-host the software and keep the encryption keys under your own control. Switching is easier because data and software are not tied to a single party.
What this means for your organisation depends on your whole stack and context. The free assessment weighs Caliopen together with your other vendors and gives a total score, a heatmap and the main risk drivers.
Top EU-based & GDPR-compliant alternatives to Caliopen
The European alternatives to Caliopen come from our knowledge base of over 3,600 vendors. We only list vendors headquartered in the EU or the EEA; fully European-owned vendors rank before vendors with a foreign owner. For each alternative you see the country, the open-source status and a short description.
- CounterMail↗
Swedish privacy-focused encrypted email (Stockholm, founded 2008) with OpenPGP 4096-bit keys and diskless web servers.
SE · commercial
Frequently asked questions
What is the best European alternative to Caliopen?
It depends on your use case. Strong EU alternatives to Caliopen include CounterMail, CTemplar and Disroot. On this page you can compare 8 EU alternatives by jurisdiction, data residency and open-source status.
Are there open-source alternatives to Caliopen?
Yes. Open-source EU alternatives to Caliopen include Disroot. These keep your data fully under your own control and let you self-host if you want to.
Is Caliopen GDPR-compliant and where is the data hosted?
Caliopen is headquartered in LU (EU) and hosts data in EU. It is also open-source, so you can self-host it. That makes Caliopen an EU-sovereign choice in its own right; the EU alternatives on this page are comparable European tools.
Digital sovereignty in Email (Personal)
Email (Personal): Personal email services — inbox, calendar, contacts. In this category the choice of vendor determines who has legal access to your data, where that data lives and how easily you can switch later.
Also in this category
How sovereign is your whole stack?
Start with Caliopen and add the rest of your software. You immediately see the score, the heatmap and the European alternatives.
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