
Five of the six fax services compared here are run by European companies, but only some keep your faxes in Europe. Fax.Plus, from Switzerland-based Alohi SA, lets Enterprise admins choose EU storage regions such as Germany or France. Retarus is German. iFax (UK) and Comfax (Cyprus) host in the US, and eFax belongs to a US group. Here is who runs each service and where your data is stored.
| Service | Company behind it | Where fax data is stored | Best for |
|---|---|---|---|
| Fax.Plus | Alohi SA, Geneva, Switzerland | Swiss data centers by default; on Enterprise, 40+ selectable locations including Germany and France, with backups set separately | Most European teams: EU storage you control, plus webhooks, MCP, and ChatGPT and Claude integrations |
| Retarus | retarus GmbH, Munich, Germany | Describes regional processing for the EU, US, and APAC | Managed deployments bought through sales or partners |
| eFax | Irish contracting entity for European numbers, within the US-based Consensus group | eFax Corporate UK says data can stay in the UK | Existing eFax Corporate customers with a UK requirement |
| iFax | Amplify Ventures Limited, London, United Kingdom | Primary AWS data center in Oregon, US; other regions on demand | Teams that want a UK supplier and accept US hosting |
| Comfax | Municorn Limited, Limassol, Cyprus | Azure servers in the US plus Google multiregional infrastructure | Individual app users rather than regulated teams |
| CocoFax | Not clearly identified in its public legal pages | Claims Swiss data centers | Light use, after confirming who you contract with |
Five of these six services are run by companies registered in Europe. Where they keep your faxes is a different question, and the answers range from a selectable German or French region to servers in Oregon. We compared company identity and documented storage using public sources checked on November 9, 2026. We publish Fax.Plus, and we apply the same tests to our own service as to the others.
Start with the requirement behind the search. Procurement may want a supplier incorporated in Europe. IT may need fax documents stored in Germany. Legal may need to understand the contracting entity, subprocessors, and international transfers. Each requirement leads to a different shortlist, so check four things:
Switzerland and the United Kingdom are in Europe but not in the EU. If your policy says “EU only,” write that down; if Swiss or UK services are acceptable, say so just as clearly. Our fax data residency guide explains how to map each type of data before choosing a region.
Fax.Plus is provided by Alohi SA, incorporated in Switzerland and based in Geneva, and is used by organizations such as the United Nations, PwC, and IBM. It is the only service in this comparison that combines a European company with storage you control yourself: on Enterprise, owners and admins choose from more than 40 locations, including Germany, France, and other EU countries, for stored sent and received fax files, and pick a separate region for backups. Without that setting, faxes are stored in Swiss data centers.
Security is documented in the same detail. Stored files use AES-256 encryption with a unique key for each user, and connections between the apps and servers use TLS. Two-factor authentication is available on every plan and team owners can enforce it, while Enterprise adds SSO. Alohi maintains ISO 27001 certification and a SOC 2 Type 2 report, and Enterprise covers HIPAA with a signed BAA. See how Fax.Plus protects your documents for the details.
It is also the most advanced platform here for automation and AI. Fax.Plus has an official app in ChatGPT and an official connector in Claude, both connected with OAuth, so your team can send and track faxes from the assistants they already use. The same hosted MCP server works with any MCP-compatible assistant, on paid plans from Basic. For developers, webhooks come with HMAC signatures, per-number routing, delivery logs, automatic retries, replay of failed events, and alerts when an endpoint starts failing, while Fax Streaming pushes each inbound page as it arrives. See Fax.Plus for AI assistants and our fax API comparison.
The everyday platform is just as complete: web, desktop, iOS, and Android apps on the same numbers, roles and shared numbers for teams, and free fax number porting on eligible paid plans.
Region selection is an Enterprise feature, and the MCP server is not available on accounts with Advanced Security Controls enabled, which HIPAA accounts require. Enterprise costs $79.99 per month billed annually, with 4,000 pages and unlimited users. The selected region covers stored fax files and backups; raw uploads, faxes in transmission, metadata, and cached thumbnails are processed in Geneva and Zurich. The data residency FAQ lists each category. For the wider operational picture, see our enterprise fax comparison.
Retarus is a German company. Its legal notice names retarus GmbH, with global headquarters in Munich.

Its compliance page describes the company as privately owned with European and American headquarters, and describes dedicated regional data processing for the EU, US, and APAC (source: Retarus compliance and regulations page).
Retarus does not publish fax pricing. You buy through its sales team or a partner such as a system integrator or reseller, so you cannot test the service or model costs before a sales process starts.

The regional commitment also depends on the agreement. Confirm which fax product, region, and backup arrangement the processing statement covers, and whether any data categories are excluded.
eFax customers with a European fax number contract with an Irish company. The eFax customer agreement names Consensus Cloud Solutions International Ltd. (“Consensus Ireland”) as the provider for numbers local to the United Kingdom or the European Union.

For eFax Corporate, the UK FAQ says the service can keep customer data in the UK at all times.

The contract is Irish, but the eFax brand belongs to Consensus Cloud Solutions, a US-headquartered group. The in-country statement appears on the eFax Corporate UK pages, not on the self-serve plans, and it covers the UK rather than the EU. Ask for the data location to be written into your eFax Corporate agreement.
iFax is a British company. Its terms identify Amplify Ventures Limited, registered in England and Wales with an office in London, as the provider.

A UK company does not mean UK hosting. iFax's security page says it runs on Amazon Web Services with its primary data center in Oregon, and that other regions are brought up on demand (source: iFax security and compliance page). If storage location matters, ask which region your account would use; there is no documented self-serve EU storage setting.
Comfax, sold as Fax App, is run by Municorn Limited, which gives its address in Limassol, Cyprus. That makes it the only provider here registered in an EU member state.

The privacy policy states that Fax App runs on Azure servers located in the USA and on Google multiregional infrastructure, and it lists US fax services such as Phaxio and Documo mFax among its service providers. An EU address therefore does not mean EU storage.

CocoFax says it stores private data in Swiss data centers, and its terms refer to Geneva law.

Neither statement identifies the company you would contract with. The public legal pages we reviewed did not name a registered entity or owner, so ask for the company name, registration number, and a data processing agreement before treating CocoFax as a Swiss provider. We have not independently verified its data center claim.
Write the requirement in one sentence before comparing plans. “We need a European fax service” is too broad to test. “We need a Swiss or EU provider, fax documents stored in Germany, and a documented backup region” gives procurement and IT something they can verify.
If automation is central to the decision, continue with our fax API comparison.
No. GDPR does not require every supplier to be incorporated in the EU or every processing operation to happen there. The European Commission explains that transfers outside the EEA can rely on several transfer mechanisms, and its adequacy list includes Switzerland and the United Kingdom. Your organization still needs a legal basis, suitable contracts, access controls, and retention rules, and a customer contract or internal policy may set a narrower geographic condition than GDPR itself.
For most European teams, Fax.Plus is the best online fax service in this comparison. It is the only one that pairs a clearly identified European company with fax storage you can place in Germany, France, or another EU location yourself, backed by ISO 27001, SOC 2 Type 2, SSO, and published pricing. It is also the only one in this comparison with an official ChatGPT app and Claude connector, alongside production-grade webhooks.
The others fit narrower situations. Retarus suits organizations that want a managed German service and are ready for a sales-led purchase. eFax Corporate works for existing customers with a UK requirement. iFax and Comfax are European companies whose documented hosting is in the US, which matters if storage location is the reason you are searching. CocoFax needs its company identity confirmed first. To check Fax.Plus against your requirements, talk to our team about regional storage.
