Claws Mail vs Thunderbird (2026): which should you pick?
As of Nov 12, 2026, Thunderbird grades higher than Claws Mail: 3.2 against 2.8 out of 4.0.
Checked Oct 5, 2026 and Nov 12, 2026 · graded Oct 10, 2026 and Nov 12, 2026 by ToolGPA
Thunderbird grades higher on features and platforms. They get the same grade on value for money, the free plan and ease of use.
Price, platforms and features side by side. The table says where each price was read and when.
Thunderbird
Free, open-source email app for Windows, macOS, Linux and Android
Free
Which one is for you
Pick Claws Mail if
- Fits if you want a light mail client you can drive from the keyboard
- Works for people who use GnuPG and want plugins for extras
Look elsewhere if
- Skip it if you want a calendar built in, as that's a plugin
- Not for you if you use a Mac, since the downloads page mentions no macOS version
- Watch out: Windows is a separate port
- Too light on looks if you want a modern design: the interface is built on GTK and follows older desktop mail clients
Pick Thunderbird if
- Fits if you want a free desktop email app with no ads in it
- Works for people who move between Windows, macOS and Linux and want the same app on each
Look elsewhere if
- Skip it if you're on an iPhone, as Thunderbird Mobile is listed for Android only
- Not for you if you want someone to call when it breaks, because support is community-based
- Too light for anyone who needs an email address as well, since it's a mail app, not a mailbox
- Watch out: Thundermail, the team's own hosting, is a separate paid beta behind a waitlist, $6 a month yearly
- Skip it if you read mail in a browser, as there's no web version
How we grade them
| 2.8GPAClaws MailGood | 3.2GPAThunderbirdVery good | |
|---|---|---|
| Value for money | AFree under the GPL for anyone to download. A program anyone can download and run counts as free and substantial. | AIt's free, where the middle of this category is $8 a month. Every feature of the desktop and Android apps costs $0, with no ads and no paid tier, funded by voluntary donations. Thundermail, the team's own hosting service, is a separate paid subscription and still in beta. |
| Free plan and trial | AFree outright, the whole app, with no paid edition. | AThe whole app is free on desktop and Android, with no cap and nothing held back for a paid plan, because there isn't one. The trade-off is support: it's community-based, and Thunderbird says donations don't buy individual technical help. |
| Features | CA keyboard-driven client with filtering, search, GnuPG, plugins, several protocols and MH storage. Gaps: calendar and RSS are plugins, not the base app. | BSeveral accounts read separately or in a unified inbox, with calendar, contacts and tasks in the desktop app so scheduling needs no second program, add-ons to extend it, and OpenPGP on Android through OpenKeychain. Nothing in the listing points at a hole in the mail-client job. |
| Ease of use | CNo store rating on record. You install from a distro package or source, connect your accounts and add plugins for extras. | CNo rating on record, and this is a settings-heavy old hand rather than a tidy modern app: accounts to add, panes and add-ons to arrange, and community forums if you get stuck. A QR code copies your desktop accounts to the Android app. |
| Platforms and integrations | CLinux, plus a separate Windows port. No macOS version is mentioned and there's no phone or web version. | BWindows, macOS and Linux on the desktop and Android on the phone, so computer and phone are covered and Linux people are included for once. No iPhone or iPad app is listed, there's no web version, and the only integration on record is OpenKeychain. |
| Best for | a lightweight keyboard-driven mail client | free, open-source email on any desktop |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: Claws Mail and Thunderbird. How we grade
Price against what you get
Claws Mail has no paid plan and scores 2.0 out of 4 on features, ease of use and platforms. Thunderbird has no paid plan and scores 2.7.
Thunderbird scores higher for the same starting price. Of the other email apps on the chart, none scores higher than Claws Mail for less, and none scores higher than Thunderbird for less.
Features, ease of use and platforms, averaged
What paid plans start at, a month (each step along is roughly double) →
- The best score at each price
- Has a free plan
- No free plan
Where they differ
- Claws Mail also covers inbox filtering.
- Thunderbird also covers tasks and calendar.
In commonFree planLinuxWindowsOpen sourceEmail client
At a glance
| Claws Mail | Thunderbird | |
|---|---|---|
| Pricing | Free | Free |
| Starts at | Free | Free |
| Free plan | The whole application is free software under the GPL. | The whole app is free on desktop and Android, with no ads and no paid tier. Development is funded by voluntary donations. |
| Free trial | None listed | None listed |
| macOS | ||
| Windows | ||
| Linux | ||
| Android | ||
| Made by | Claws Mail project | MZLA Technologies Corporation |
| Price read from | claws-mail.org | thunderbird.net |
| Checked | Nov 12, 2026 | Oct 5, 2026 |
Worth knowing
Claws Mail
- Calendar and RSS are plugins, not part of the base application.
- Windows is listed as a separate port; no macOS version is mentioned on the downloads page.
- The interface is built on GTK and follows the look of older desktop mail clients.
Thunderbird
- Thunderbird Mobile is listed for Android only, through Google Play and F-Droid. No iPhone or iPad app is listed.
- It is a mail client, not a mailbox: it connects to accounts hosted elsewhere. The team's own hosting service, Thundermail, is in beta behind a waitlist.
- Thundermail is a separate paid subscription. Its Early Bird Plan is shown at $6 per month, paid annually, with full launch expected in 2026.
- Support is community-based. Thunderbird states that donations do not buy individual technical support.
Key features
Claws Mail
- Keyboard-driven interface
- Almost all commands can be reached from the keyboard, in a layout meant to look familiar to people from other mail clients.
- Filtering and search
- Filtering, per-folder processing, message scoring, colour labels and a search function for sorting a busy mailbox.
- GnuPG support
- Encrypt and sign messages with GnuPG through GPGME, and switch the encryption type while composing.
- Plugins
- Extras such as an RSS aggregator and a calendar come as plugins, and the project lists them on a plugins page.
- Protocols and accounts
- Multiple accounts over POP3, IMAP4rev1 and SMTP with SSL, plus Usenet news reading and posting through NNTP.
- MH storage and import
- Messages are kept in the MH format, and mbox import and export lets you move mail in and out of other clients.
Thunderbird
- Unified inbox for several accounts
- Keep every email account in one app and read them separately or together in a unified inbox, on desktop and on Android.
- Calendar, contacts and tasks
- The desktop app manages appointments, contacts and tasks alongside email, so scheduling does not need a separate program.
- No ads or data mining
- Thunderbird says it does not sell ads in the inbox, collect personal data or train AI on private conversations. It is funded by user donations.
- Open source and extensible
- The code is published under the MPL 2.0 license for anyone to inspect, modify and share, and add-ons extend what the desktop app can do.
- OpenPGP encryption on Android
- Advanced users can send and receive encrypted mail with the OpenPGP standard by pairing Thunderbird Mobile with the free OpenKeychain app.
- Desktop-to-mobile setup
- Desktop users can move their account settings to the Android app by scanning a QR code shown in the desktop app.
Plans
Claws Mail
Claws Mail$0
Free under the GPL; install from a distribution package or the source tarballs.
Thunderbird
Free$0
Every feature of Thunderbird Desktop for Windows, macOS and Linux and of Thunderbird Mobile for Android.
Common questions
Which is cheaper, Claws Mail or Thunderbird?
As of Nov 12, 2026, both Claws Mail and Thunderbird are free to use.
Which has a free plan, Claws Mail or Thunderbird?
As of Nov 12, 2026, both Claws Mail and Thunderbird have a free plan.
Which platforms do Claws Mail and Thunderbird run on?
As of Nov 12, 2026, only Thunderbird lists macOS and Android apps. Both list Windows and Linux apps. A platform missing from a listing is one its maker's pages did not mention.
More comparisons
How this page was made
- The verdict at the top follows a fixed rule. When both tools are in the same category and either is in our top three for it, the verdict follows that ranking: the higher-placed tool is our pick. The top three weigh who each tool suits as well as its grades, so a pick can go against the GPA. Otherwise the page does not pick one and says which grades higher: the higher GPA first; on a tie, the one with a free plan, then the one that starts cheaper in dollars a month, counted the same way for both; if they are still level, what the choice depends on.
- The grades are our own, from each tool’s review or report card. The GPA is their average.
- Prices, plans and platforms come from each tool’s listing. The table above says where each price was read and when.
- The differences and the answers to the questions are worked out from those listings.