Open source Thunderbird alternatives

All Thunderbird alternatives

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   Mailspring

   17.9KstarsLike

   Mailspring is a free, open-source desktop email client for Windows, macOS and Linux that works with Gmail, Office 365, iCloud and any IMAP account. It offers a unified inbox, fast search, themes and templates, and runs its mail sync engine locally rather than in the cloud. An optional Pro subscription adds read receipts, link tracking, send later and reminders.

   7 Mailspring alternatives

   Pros

   • Free and open source on Windows, Mac and Linux
   • Sync engine runs locally rather than through a cloud service
   • Unified inbox, themes and templates in a clean interface

   Cons

   • Send later, reminders and read receipts require Pro
   • A Mailspring ID account is required even for the free version
   • No mobile apps to go with the desktop client

   Cost / License

   FreemiumOpen source

   Categories

   Email Clients & Providers

   Platforms

   WindowsMacLinux

   Features

   Dark modeEmail trackingSend laterTemplatesUnified inbox

   Visit websiteMore about Mailspring
2. 

   

   Proton Mail

   4.8(48.7K) · App StoreLike

   Proton Mail is an end-to-end encrypted email service based in Switzerland. Messages between Proton users are encrypted automatically, emails to others can be password-protected, and stored mail uses zero-access encryption so Proton cannot read it. Its apps are open source, paid plans add custom domains and more addresses, and it is part of a suite with Proton Calendar, Drive, VPN and Pass.

   9 Proton Mail alternatives

   Pros

   • End-to-end and zero-access encryption protect stored mail
   • Based in Switzerland, with open source apps
   • Part of a suite with Proton Calendar, Drive, VPN and Pass

   Cons

   • Free plan is tight on storage and addresses
   • Using IMAP clients requires Proton Mail Bridge and a paid plan

   Cost / License

   FreemiumOpen source

   Categories

   Email Clients & Providers

   Platforms

   WebWindowsMacLinuxiPhoneAndroid

   Features

   Custom email domainEmail aliasesEnd-to-end encryptionSend laterTracker blockingTwo-factor authentication

   Visit websiteMore about Proton Mail
3. 

   

   Tuta

   4.7(3.7K) · App StoreLike

   Tuta, formerly Tutanota, is an open-source encrypted email and calendar service based in Germany. It encrypts mailbox contents end to end, including subject lines and contacts, and uses post-quantum cryptography for new accounts. Because it relies on its own encryption, it works through Tuta's apps rather than IMAP clients. A free plan exists, and paid plans add custom domains and more aliases.

   7 Tuta alternatives

   Pros

   • Encrypts subjects and contacts, not just message bodies
   • Post-quantum cryptography for new accounts
   • Open source apps and a free plan, with servers in Germany

   Cons

   • No IMAP support, so you must use Tuta’s own apps
   • Free plan is limited in storage and features
   • Fewer integrations and features than mainstream providers

   Cost / License

   FreemiumOpen source

   Categories

   Email Clients & Providers

   Platforms

   WebWindowsMacLinuxiPhoneAndroid

   Features

   Calendar viewCustom email domainEmail aliasesEnd-to-end encryptionGDPR compliant

   Visit websiteMore about Tuta