Tuta

Active

Country: Germany (DE)
Founded: 2011
Developer: Tutao GmbH
Pricing: Freemium
Open source: Yes
Platforms: Android, iOS, Linux, macOS, Windows, Web

Indexes

Calendar Email Clients

Overview

Tuta is an end-to-end encrypted email, calendar, and contacts service developed by a German company. It provides secure communication tools with quantum-resistant encryption, targeting users seeking privacy without tracking or ads. The service supports free accounts alongside paid options and has over 10 million users.¹²

Key Features

End-to-End Encryption - Encrypts emails, calendars, and contacts with zero-knowledge architecture.
Quantum-Resistant Cryptography - Uses TutaCrypt hybrid protocol introduced in 2024 for post-quantum security.
Tuta Calendar - Integrated encrypted calendar app, standalone on iOS/Android since 2024, Thunderbird add-on since 2026.
Open Source Clients - Desktop and mobile apps available on GitHub for third-party verification.
Push Notifications - Supports notifications on mobile even when logged out.
No Ads or Tracking - Ad-free service with no user profiling.
Shared Mailboxes - Supports encrypted shared mailboxes and identities.

Pricing

Plan	Price	Includes
Free	Free	Basic encrypted email, calendar, contacts with limited storage.
Premium	Paid (yearly/monthly)	Increased storage, custom domains, more aliases, priority support.

Platforms & Requirements

Tuta runs on Android (via Google Play, F-Droid, direct download), iOS (App Store), Linux, macOS, Windows (desktop apps), and web. Mobile apps provide full encryption and push notifications; desktop apps are open source. No specific minimum requirements noted beyond standard OS versions.²³⁴⁵

Integrations & Ecosystem

Thunderbird (calendar add-on)
F-Droid (Android)
Import/export capabilities
GitHub for code review
Email to non-Tuta users (encrypted)

Alternatives

App	Difference
Proton Mail	Swiss-based with similar E2EE but different encryption protocols and pricing.
StartMail	Paid-only service focused on anonymity without free tier.
Mailbox.org	German provider offering email/calendar with E2EE but less emphasis on quantum resistance.
Posteo	Privacy-focused email from Germany without open-source clients.

Reputation

Tuta is recognized for strong privacy features, end-to-end encryption, and open-source code, attracting over 10 million users. Strengths include quantum-resistant tech and no-tracking policy under German jurisdiction. Criticisms may involve freemium limitations on storage and features compared to paid rivals.¹²³

Sources (9)