# Thunderbird

> Free, open-source email app for Windows, macOS, Linux and Android

Thunderbird is a free, open-source email app with a calendar, contacts and tasks built in. The desktop version runs on Windows, macOS and Linux and the mobile version on Android, and both handle several accounts separately or in a unified inbox. It is funded by donations rather than ads or data sales, and is developed by MZLA Technologies Corporation, a subsidiary of Mozilla.

- **Category:** Email Apps
- **Made by:** MZLA Technologies Corporation (since 2003)
- **Website:** https://www.thunderbird.net
- **Runs on:** Windows, macOS, Linux, Android
- **Facts last checked:** Oct 5, 2026

## Pricing

Thunderbird is free to use.

- **Pricing model:** Free
- **Free plan:** 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.

| Plan | Price | What you get |
| --- | --- | --- |
| Free | $0 | Every feature of Thunderbird Desktop for Windows, macOS and Linux and of Thunderbird Mobile for Android. |

Read from https://www.thunderbird.net/en-US/ on Oct 5, 2026. Prices change, so confirm with Thunderbird before buying.

## Key features

- **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.

## Good for

- People who want a free desktop email app without ads
- Linux users, and anyone moving between Windows, macOS and Linux
- Those who prefer open-source software for mail and calendar

## Worth knowing

- 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.

## Works with

OpenKeychain

**Tags:** Email client, Open source, Calendar, Tasks

## Alternatives

- [Microsoft Outlook](https://toolgpa.com/tools/microsoft-outlook): Microsoft's email and calendar app for desktop, mobile and web. [Compare](https://toolgpa.com/compare/microsoft-outlook-vs-thunderbird)
- [eM Client](https://toolgpa.com/tools/em-client): Desktop email client for Windows and Mac with calendar and chat. [Compare](https://toolgpa.com/compare/em-client-vs-thunderbird)
- [Mailbird](https://toolgpa.com/tools/mailbird): Desktop email client for Windows and Mac with a unified inbox. [Compare](https://toolgpa.com/compare/mailbird-vs-thunderbird)
- [Apple Mail](https://toolgpa.com/tools/apple-mail): Free built-in email app for iPhone, iPad and Mac. [Compare](https://toolgpa.com/compare/apple-mail-vs-thunderbird)
- [Mailspring](https://toolgpa.com/tools/mailspring): Open-source desktop email client for Mac, Windows and Linux. [Compare](https://toolgpa.com/compare/mailspring-vs-thunderbird)

## Sources

The prices, plans, platforms and features above were read from these pages on Oct 5, 2026:

- https://www.thunderbird.net/en-US/
- https://www.thunderbird.net/en-US/desktop/
- https://www.thunderbird.net/en-US/mobile/
- https://www.thunderbird.net/en-US/about/
- https://www.thunderbird.net/en-US/donate/
- https://www.tb.pro/en-US/
- https://play.google.com/store/apps/details?id=net.thunderbird.android&hl=en_US&gl=US

Page: https://toolgpa.com/tools/thunderbird
Listed by ToolGPA (toolgpa.com).