MailspringLinux
vs
ThunderbirdWindows
Mailspring as a Linux alternative to Thunderbird
Updated
Our verdict
Mailspring can replace Thunderbird for users whose primary need is a fast, modern email client with a unified inbox, snooze, and send‑later features. It works well on Linux, uses less RAM, and keeps credentials local. However, it lacks built‑in calendar, contact manager, RSS reader, chat protocols and Usenet support, so anyone relying on those Thunderbird extensions will miss functionality. For users who just need solid IMAP/POP3 handling and appreciate a sleek UI, Mailspring is a good fit; power users who need the full suite of Thunderbird’s integrated tools should stay with Thunderbird or add separate Linux apps for those missing pieces.
- License
- GPL-3.0+
- Price
- Free
- Latest version
- 1.26.1 (October 20, 2026)
- Rating
- —
What works the same
- Both are free, open‑source email clients
- Support IMAP and POP3 accounts
- Multiple account handling with unified view
- Local storage of messages and credentials
What is different
- Mailspring has no built‑in calendar or task integration
- No native contact manager, RSS feed reader, or chat (IRC/XMPP/Matrix)
- No Usenet/NNTP support
- Advanced features like link tracking require a paid Pro subscription
Opening your Thunderbird files
Mailspring cannot directly open Thunderbird's profile files (mbox, .msf, or SQLite address books). You would need to export messages from Thunderbird (e.g., as mbox) and then import them into Mailspring, which can read standard mbox files. Contact and calendar data must be exported separately (CSV/vCard, iCal) and imported into other Linux tools.
Switching from Thunderbird to Mailspring, step by step
- Export Thunderbird mail folders as mbox files (Tools → ImportExportTools NG).
- Copy the mbox files to a folder accessible to Mailspring.
- In Mailspring, add a new account and choose "Import" to point to the mbox folder.
- Export contacts from Thunderbird as vCard or CSV and import them into your preferred Linux contacts manager.
- If you need a calendar, export Thunderbird events as iCal and import them into a separate Linux calendar app (e.g., Evolution or Thunderbird again).
Key features of Mailspring
- C++ sync engine based on Mailcore2
- Unified Inbox for multiple accounts
- Snooze and Send Later functionality
- Mail Rules and Templates
- Local-first architecture (no cloud credentials)
- Low RAM and CPU usage
- Mailspring Pro adds link tracking and analytics
How to install Mailspring on Linux
flatpak install flathub com.getmailspring.MailspringFrequently asked questions
Does Mailspring support calendar invites?
No, Mailspring does not include a calendar component; you need a separate calendar application to handle .ics files.
Can I keep my Thunderbird extensions when switching?
Mailspring does not use Thunderbird's extension system, so extensions are not transferable.
Is Mailspring’s Pro subscription required for basic email use?
No, the free version provides all core email functions; Pro only adds analytics, link tracking and similar marketing‑oriented tools.
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