Self-hosted / open sourceOffice & ProductivityHeadquarters: AT

grommunio: sovereignty score and 8 European alternatives

grommunio is an open-source collaboration platform from grommunio GmbH in Vienna, which presents itself as a drop-in replacement for Microsoft Exchange. It combines email, calendars, contacts, tasks and notes with chat, video meetings, file sharing and an online office suite behind a single login. It supports protocols such as MAPI/HTTP, EWS, Exchange ActiveSync, IMAP, POP3, SMTP and LDAP or Active Directory, so existing clients can often keep working. Native and web clients exist for Linux, Windows, Apple and Android. The software is offered as an appliance or for manual installation.

You can run grommunio yourself, in a private cloud, or through a certified partner that handles hosting. The vendor states that it does not store customer data itself; data resides wherever you operate the infrastructure. The core, gromox, and the web interface are published on GitHub. A commercial subscription adds long-term maintenance and manufacturer support. The company is based in Austria, an EU member state, and no foreign parent company is known.

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Sovereignty score

94 / 1000 = high exposure
100 = sovereign

Jurisdiction SOV-2100
Headquartered in the EU: European law applies
Data residency SOV-3100
EU-only hosting
Cryptographic key sovereignty SOV-390
Self-hostable: encryption keys under your own control
Freedom from lock-in SOV-680
Open source: low switching costs
Source & runtime sovereignty SOV-4 · SOV-6100
Source code auditable, forkable and self-hostable

SOV codes: the matching objective in the European Commission's Cloud Sovereignty Framework. Official source

How the score is calculated

Facts and evidence

Last checked October 4, 2026

Headquarters	AT (EU)Verified by hand
Sovereignty model	Open-source, distributedVerified by hand
Data hosting	EUVerified by hand
Open-source	YesVerified by hand
GDPR-compliant	YesVendor-stated
Hosting signal	CLOUDFLARENET - Cloudflare, Inc., US (US)Technically measured
Category	Office & Productivity
Type	Product
Website	grommunio.com ↗

The hosting signal shows the network that serves the vendor's website, often a CDN, and not necessarily where the service or your data is hosted. How we verify · Something wrong? Suggest a correction

Top EU-based & GDPR-compliant alternatives to grommunio

The European alternatives to grommunio come from our knowledge base of over 6,800 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.

Score per alternative: 0 = high exposure, 100 = sovereign

31 European Office & Productivity vendors are in the catalogue. View the whole category · Submit an alternative · View category on the map

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Why digital sovereignty matters with grommunio

grommunio is headquartered in AT 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 grommunio scores best on data residency.

grommunio 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 grommunio together with your other vendors and gives a total score, a heatmap and the main risk drivers.

Frequently asked questions

What is the best European alternative to grommunio?

It depends on your use case. Strong EU alternatives to grommunio include Ashampoo Office, Calligra Suite and Craft Docs. On this page you can compare 8 EU alternatives by jurisdiction, data residency and open-source status.

Are there open-source alternatives to grommunio?

Yes. Open-source EU alternatives to grommunio include Calligra Suite, CryptPad, EGroupware, Euro-Office, eXo Platform and Framasoft (Framapad/Framacalc). These keep your data fully under your own control and let you self-host if you want to.

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

grommunio is headquartered in AT (EU) and hosts data in EU. It is also open-source, so you can self-host it. That makes grommunio an EU-sovereign choice in its own right; the EU alternatives on this page are comparable European tools.

Details and sources

Verified by handHeadquarters, owner, hosting locations and licence have been checked by us against public sources. Free of charge and for every vendor, not a paid label. Nothing in this knowledge base is taken over automatically. Last checked on October 4, 2026.

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

Digital sovereignty in Office & Productivity

Office & Productivity: Office software, word processing, spreadsheets and groupware. 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.

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