Thunderbird Send — Thundermail

Thunderbird Send makes sending large files safe and easy, with end-to-end encryption that keeps them secure in any recipient’s inbox.
Share large files with end-to-end encryption and fewer limits. Send provides a natural file attachment experience in Thunderbird Desktop and is compatible with any recipient’s inbox. Know your attachments will arrive safe and secure.
Your files are protected from the moment they leave your device until they reach their destination. With encryption both in transit and at rest, plus optional password protection, sensitive documents stay private, so even we can’t see what you’re sharing.
Share files up to 20GB without worrying about attachment restrictions. Whether it’s high-resolution photos, design files, or project archives, Send handles what traditional email can’t, while maintaining the familiar attachment experience in Thunderbird Desktop.
Send large files directly from Thunderbird Desktop just like any other attachment. Recipients with Thunderbird see your files as natural email attachments, others can access them securely via a link.
The technology powering Thundermail is freely licensed and open source, offering you transparency, security, and freedom. By subscribing you fund the development of our other open source tools which remain free-of-charge, free-of-ads, and free-of-data-harvesting.
Thundermail is part of our mission to help you communicate, collaborate, and connect freely. The Thunderbird Desktop and Mobile apps remain the core of how we offer these benefits and your subscription helps us make them even better.
Money isn’t our mission, it is the means to bring freedom and productivity to as many people as possible. Freely licensed software, open source code, and open standards liberate you and remain at the heart of Thunderbird.
Get Thundermail, Appointment, and Send in one simple subscription. You’ll love the confidence, ease, and security these services add to Thunderbird. Thank you for supporting freedom.
Our initial offering, ideal for most users
30 GB of Mail Storage
60 GB of Send Storage
1 Inbox, 15 Email Addresses
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