Kitsmith / Utilities / Mozilla Thunderbird
Mozilla Thunderbird
Free forever (donation-supported) · Open source
Price checked at source September 18, 2026.
A free, open-source, donation-funded email client from the Mozilla family — unified inbox, calendar and contacts, and no ads or AI training on your mail.
Our take
The privacy-first default for people who’d rather not hand an inbox to a company whose business model depends on reading it. Thunderbird explicitly states it doesn’t collect personal data, sell inbox ads, or train AI on user messages, and funds development through donations rather than a paid tier. It’s built and maintained by a dedicated staff under MZLA, a for-profit Mozilla subsidiary structured specifically to sustain the free, open-source project long-term — not a side project. Cross-platform (Mac, Windows, Linux), with a newer mobile app for Android.
- Price
- Free forever (donation-supported)
- License
- Open source
- Requires
- macOS, Windows, and Linux; a companion Android app is also available.
- Get it via
- Direct · Homebrew
Do you use Mozilla Thunderbird?
Who made this
Site (opens in new tab) GitHub (opens in new tab)
Are you The Thunderbird Project (MZLA Technologies Corporation, a Mozilla subsidiary)? Claim this profile to add a photo, a bio, and links — or ask us to remove it.
What it does
Unified inbox & calendar
Manages multiple accounts, calendars, and contacts together or separately in one app.
No data collection or ad-targeting
The project states it doesn’t collect personal data, sell inbox ads, or train AI on private messages.
Deep customization
Extensible with add-ons and tagging, built for people who want to configure their client rather than accept defaults.
Cross-platform, including mobile
Runs on Mac, Windows, and Linux, with a newer Thunderbird for Android app.
The deal
- Free, open source — funded by user donations, no paid tier
Mozilla Thunderbird — questions people ask
Is Thunderbird really free?
Yes — free forever, funded by user donations rather than ads, data sales, or a paid tier.
Who develops Thunderbird?
The Thunderbird Project, operating as MZLA, a for-profit subsidiary structured to sustain the free open-source project within the Mozilla family.
Is Mozilla Thunderbird free?
Yes — Mozilla Thunderbird is free.
Does Mozilla Thunderbird work alongside a notch app like Alcove?
Yes — Mozilla Thunderbird lives in the screen, so it runs happily alongside any Dynamic Island hub or notch app.
Where can I download Mozilla Thunderbird?
Mozilla Thunderbird is available via Direct, Homebrew.
Is Mozilla Thunderbird open source?
Yes — Mozilla Thunderbird is open source.
Reviews
No public ratings yet. Reader reviews are coming to Kitsmith soon.
Listing hand-verified September 18, 2026 from the developer's site and public sources.
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