Compare Infomaniak kMail and Proton Mail on capabilities, jurisdiction, assurance, and fit for European buyers.
Both listed as alternatives to: Gmail, Outlook.com
Switzerland· Email Services
Needs review
Shortlist when you need Swiss-hosted professional email with custom domains, IMAP/CalDAV, suite bundling (kSuite), and operator-owned DCs. Skip when zero-access client-side E2EE or full self-host is mandatory—consider Proton Mail (E2EE) or a self-hosted stack instead.
Switzerland· Email Services
Needs review
Shortlist Proton Mail when you want Swiss-jurisdiction, zero-access encrypted email with open-source clients, custom domains, Bridge for desktop mailers, and a public DPA. Skip when you need free-tier IMAP Bridge, fully self-hosted FOSS mail on your own servers, or Workspace-class collaboration depth—consider Tuta, Posteo, or Mailfence among EU peers, or stay on Google/Microsoft if suite lock-in wins.
Highlighted rows differ between the two products.
| Feature | Infomaniak kMail | Proton Mail |
|---|---|---|
| Country of origin | Switzerland | Switzerland |
| Category | Email Services | Email Services |
| Open source | Yes | No |
| Self-hosted | No | No |
| Headquarters | Switzerland | Switzerland |
| Legal entity | Infomaniak Network SA (Rue Eugène Marziano 25, 1227 Les Acacias, Geneva; CH-660.0.059.996-1; IDE CHE-103.167.648) | Proton AG, Route de la Galaise 32, 1228 Plan-les-Ouates, Geneva, Switzerland (EU representative: Proton Europe sàrl, Luxembourg) |
| Governing law | Not listed | Swiss law (Terms; Geneva courts for business/non-US consumer disputes as stated in Terms) |
| US parent / control | No known US parent | No known US parent |
| CLOUD Act exposure (indicative) | Low | Medium |
| Hosting / residency | Primary mail hosting on Infomaniak-operated Swiss data centres (Geneva/Zurich region; Swiss Hosting label claimed); dual-DC backups in Switzerland. Confidentiality policy names payment partners (e.g. PayPal, Checkout) and other ancillary third parties for account/billing/measurement—not AWS/GCP/Azure as primary mail hosts in public materials. | Primary mail storage on Proton-owned servers in Switzerland (vendor security pages). Not marketed as AWS/GCP/Azure inbox hosting. Public privacy policy lists US-group processors for support and payments (Zendesk; Chargebee, Stripe, PayPal) and group support processing in North Macedonia and Taiwan; HubSpot noted for business sales inquiries. |
| Summary | Swiss-hosted professional email, contacts and calendars from Infomaniak Network SA—custom domains, open protocols, optional encryption, part of kSuite. | Swiss end-to-end encrypted email from Proton AG: zero-access inbox storage, open-source clients, custom domains, and Bridge for desktop IMAP clients. |
| Tags |
| At a glance | Infomaniak kMail | Proton Mail |
|---|---|---|
| HQ | Geneva, Switzerland (Les Acacias) | Plan-les-Ouates (Geneva), Switzerland |
| Legal entity | Infomaniak Network SA | Proton AG (CHE-354.686.492); Proton Foundation supervision |
| Hosting | Own Swiss data centres; dual-site mailbox backups | Not listed |
| Open source | Mobile clients GPL-3.0; backend SaaS | Not listed |
| Self-host | No (hosted only) | No (SaaS); clients open source |
| Commercial model | Free my kSuite tier; paid kSuite / Mail Service seats | Freemium + paid consumer and business seats |
| Hosting model | Not listed | Proton-owned hardware in Switzerland (vendor claim) |
| Bridge | Not listed | Paid plans that include Mail |
| Key capabilities | Infomaniak kMail | Proton Mail |
|---|---|---|
| Swiss-hosted mail | Yes | Not listed |
| Custom domains | Yes | Not listed |
| IMAP / CalDAV | Yes | Not listed |
| OSS mobile clients | Yes | Not listed |
| ISO 27001 (claimed) | Yes | Not listed |
| Optional send encryption | Yes | Not listed |
| E2EE + zero-access | Not listed | Yes |
| Swiss-operated | Not listed | Yes |
| Bridge (IMAP/SMTP) | Not listed | Yes |
| Open-source clients | Not listed | Yes |
| ISO 27001 & SOC 2 (claimed) | Not listed | Yes |
| Public B2B DPA | Not listed | Yes |
Custom-domain mail with IMAP, CalDAV and CardDAV
Host name@your-domain addresses with standard IMAP/SMTP plus CalDAV/CardDAV so Thunderbird, Apple Mail, Outlook and other clients stay usable. Paid kSuite/Mail Service tiers add multi-mailbox management, aliases/categories, signatures and team admin; free my kSuite is limited to one address without aliases.
One-click send-time encryption (OpenPGP / ECC / AES)
Optional encryption at send uses OpenPGP, ECC and AES-256-GCM; Infomaniak-to-Infomaniak is automatic after auth, while external recipients often open a password-protected secure page. Private keys stay on Infomaniak infrastructure—useful for sensitive sends, but not zero-access client-side E2EE with user-held keys.
Open-source Infomaniak Mail mobile clients
Official iOS and Android mail apps are published on GitHub under GPL-3.0 for local inspection and contribution. The hosted mail backend remains Infomaniak SaaS only—there is no supported self-hosted server stack for kMail.
Swiss dual-DC backups, SPF/DKIM/DMARC and antivirus
Mailboxes are backed up across Swiss data centres with vendor-stated restore windows around 30 days; anti-spam/antivirus plus domain authentication (SPF, DKIM, DMARC) are standard. Availability claims (e.g. high uptime for essential services) should be checked against the current SLA for your plan.
Sovereign AI assist (Euria) inside the mailbox
In-product AI can help draft, correct, translate and process mail context; Infomaniak states messages sent to its AI are processed in Switzerland and not stored for other purposes. Treat AI features as operator-side processing of content you choose to submit—not as end-to-end private AI.
Zero-access inbox encryption by default
Bodies and attachments are encrypted so Proton states it lacks keys to read stored mail. Proton-to-Proton traffic is end-to-end encrypted automatically; external recipients need password-protected messages or PGP/WKD for comparable content protection. Subject lines are not fully E2EE under OpenPGP header rules.
Proton Mail Bridge for desktop IMAP clients
Paid plans that include Mail can run Bridge locally to connect Outlook, Thunderbird, or Apple Mail over IMAP/SMTP while encrypting and decrypting on the device. Free accounts use official web/mobile/desktop apps instead of Bridge.
Custom domains, aliases, and business admin
Paid and business tiers support custom domains, extra addresses, catch-all and groups, hide-my-email aliases, and org admin for seats, storage, and retention policies. Suits teams leaving Google/Microsoft who still need branded addresses.
Open-source clients with published audits
Web, mobile, and desktop clients are published on GitHub with third-party audit reports linked from Proton’s open-source page. The hosted mail backend is not offered as self-hosted FOSS—audit client trust, not full server reproducibility.
Tracker blocking, PhishGuard, and Sentinel
Built-in tracker protection, phishing heuristics, link confirmation, SPF/DKIM/DMARC for custom domains, hardware-key 2FA, and optional Proton Sentinel monitoring for high-risk accounts. Complements encryption with everyday abuse defenses.
| Assurance & compliance | Infomaniak kMail | Proton Mail |
|---|---|---|
| Independent security / no-logs audit | Not found Bug bounty and ISO ISMS claimed; no public independent no-logs audit of mailbox content found. Encryption is optional and keys remain with Infomaniak. | Vendor claimed Open-source clients with published third-party audit reports (web/desktop links on open-source page). Not a classic VPN no-logs court test; transparency report covers legal orders for accessible account data. |
| ISO 27001 | Vendor claimed Vendor publishes ISO 27001:2022 certificate (certified since 2018 per certifications page); downloadable PDF and SoA references. | Vendor claimed Vendor announces ISO 27001 certification after external audit completed 2 May 2024; Trust Center links a certificate download. Confirm scope and validity at procurement time. |
| SOC 2 / SOC 3 | Not found Not listed among published certifications (ISO 27001/9001/14001/50001, B Corp, Swiss labels). | Vendor claimed Vendor announces first SOC 2 Type II attestation (July 2025 blog). Report typically under NDA—request from vendor for diligence files. |
| GDPR / EU data protection | Vendor claimed Swiss entity; GDPR and Swiss FADP commitments on legal pages; DPO listed; Swiss hosting of service data claimed. | Vendor claimed Swiss controller/processor with EU representative; public DPA; GDPR materials for business. Adequacy/transfer mechanisms documented for non-adequate destinations. |
| US CLOUD Act exposure (indicative) | Partial Swiss Infomaniak Network SA, no known US parent, own Swiss DCs for mail—not a claimed clean bill. Account payments via partners such as PayPal/Checkout (US-group) per confidentiality policy. Indicative only; not legal advice. | Partial Swiss entity / no known US parent; inbox content on Proton-owned Swiss hardware with zero-access design. Partial exposure remains via US SaaS subprocessors (Zendesk support; Stripe/Chargebee/PayPal payments) and any account metadata Proton can access under Swiss process. Not legal advice. |
| Data processing agreement (B2B) | Vendor claimed Downloadable DPA linked from trust centre (Data_Processing_Agreement (DPA).pdf). | Vendor claimed Public DPA at proton.me/legal/dpa forms part of terms when Proton acts as processor; Swiss law, Geneva jurisdiction; general authorization for listed subprocessors. |
| EU AI Act | Not applicable Euria AI assist exists inside mail; product is primarily email/hosting, not an AI-system vendor offering. | Not applicable Core product is encrypted email. Optional Scribe assistant is ancillary; not an AI-centric offering for this catalog entry. |
| Considerations & known limitations | Infomaniak kMail | Proton Mail |
|---|---|---|
| Encryption is not zero-access by default | Medium Optional send encryption keeps private keys on Infomaniak infrastructure. Operators with warrant or insider access to the platform may still access unencrypted stored mail. Practical impact: do not treat kMail as a zero-knowledge vault for all messages. | Not listed |
| SaaS-only mail backend | Low No official self-host for the mail service; exit means IMAP export/migration. OSS clients do not equal portable server stack. | Not listed |
| Free tier residency and feature caps | Low my kSuite requires OECD residency and phone verification; no aliases, limited storage, enforced free signature. Unsuitable as free global professional mail. | Not listed |
| Limited public mail-path subprocessor table | Low Hosting is own Swiss DCs per vendor docs; confidentiality policy lists payment and marketing-class third parties. Procurement should request a current subprocessor list for mailbox content paths. | Not listed |
| No HDS health-hosting cert | Medium Vendor FAQ states French HDS certification is not planned—material for French health-sector workloads. | Not listed |
| Weaker defaults outside Proton | Not listed | Medium Mail to Gmail/Outlook/others is not E2EE unless password-protected or PGP/WKD is used. Subject lines are not fully E2EE. Train users or you only protect the Proton-stored copy. |
| US support and payment processors | Not listed | Medium Zendesk, Chargebee, Stripe, and PayPal appear in the public processor list. They should not see zero-access message bodies, but support content and billing data can touch US-group services—document this in DPIAs. |
| Bridge requires paid Mail | Not listed | Low Desktop IMAP/SMTP via Bridge is not available on free accounts. Budget seats for users who refuse the official apps. |
| Hosted service, not self-hosted FOSS mail | Not listed | Medium Open-source clients improve inspectability but you still depend on Proton’s operated backend, uptime, and Swiss legal process. Unsuitable if policy mandates customer-operated mail servers. |
| Swiss legal orders on accessible data | Not listed | Low Transparency reports show thousands of yearly legal orders for Mail with many complied. Bodies stay encrypted; recovery emails, IPs (when retained for abuse), and similar metadata may still be in scope. Align expectations with counsel. |
When: You need zero-access end-to-end encryption as the default mail model
Consider: Proton Mail
Different trust model: client-side E2EE vs Infomaniak operator-held keys for optional encryption
When: You want European hosted mail with a different encryption or non-profit posture
Consider: Mailfence or Posteo
Compare encryption UX, storage model, and commercial terms on each vendor site
When: You need full control of the MTA and storage stack
Consider: Self-hosted mail (e.g. mailcow/Stalwart) or a host that publishes server software
Infomaniak mobile apps are OSS; the hosted service is not self-hostable
When: You want German E2EE email with a different crypto product surface and may not need Proton’s full ecosystem
Consider: Tuta
Compare desktop interoperability and business admin maturity side by side.
When: You want ad-free European mail with strong transport privacy but do not require zero-access E2EE for all stored content
Consider: Posteo
Different threat model: Posteo is privacy-forward without Proton’s zero-access default.
When: You need OpenPGP-centric mail with classic collaboration extras under Belgian operation
Consider: Mailfence
Weigh automatic Proton-to-Proton E2EE UX versus Mailfence’s model.
When: Collaboration suite depth and ecosystem lock-in outweigh encryption defaults
Consider: Google Workspace or Microsoft 365
Accept US-provider jurisdiction and scanning/processing models as tradeoffs.