Open Source Proton Mail Alternatives
A curated collection of the 1 best open source alternatives to Proton Mail.
The best open source alternative to Proton Mail is Twake Mail. If that doesn't suit you, we've compiled a ranked list of other open source Proton Mail alternatives to help you find a suitable replacement.
Proton Mail alternatives are mainly Email & Communication. Browse these if you want a narrower list of alternatives or looking for a specific functionality of Proton Mail.
Multi-platform email client built on the JMAP protocol, for organizations running Twake Mail or any other JMAP server.
Twake Mail is an email client from Linagora that speaks JMAP rather than IMAP, written in Flutter so one codebase covers phones, tablets and the web. It removes the need to maintain a separate native client per platform, and the need to accept whatever client a mail provider ships.
The argument for the switch is that IMAP was designed in another age and grew into a chatty patchwork of extensions, heavy on bandwidth and round trips, which is why large providers wrote proprietary protocols instead. JMAP answers that with HTTP and JSON, and Linagora maintains a Dart JMAP client for anyone writing their own application.
What ships today is a straightforward client for reading, sending and searching mail.
- Mobile apps: Android and iOS builds are published by Linagora on both app stores.
- Large screens: tablets and wide layouts were handled early rather than stretched to fit later.
- Web client: an early web build ships as a Docker image and reads the server address from an environment file.
- Server choice: the client works against any JMAP server, not only the Twake Mail backend.
- Branding: documentation covers changing logos and customizing the application grid.
A Docker Compose file brings the web client up alongside a test backend with demo accounts, and translations come through Weblate. Richer filters, labels, delegated access, restoring deleted messages and a GPG encrypted mailbox are described as work in progress rather than finished. Calendar and contacts extensions are out of scope, being neither standardized as RFCs nor implemented on the backend.
