K-9 Mail

Take control of your email with K-9 Mail, the open source email client that puts privacy and flexibility first. Works seamlessly with virtually every email provider, giving you freedom from vendor lock-in and corporate tracking.

Manage all your accounts in one place with unified inbox support, so you never miss an important message across multiple email addresses. Switch between accounts instantly or view everything together — your choice.

Your privacy matters. K-9 Mail connects only to your email provider with zero tracking, no data harvesting, and complete transparency. Unlike mainstream email apps, your messages stay yours alone.

Stay synchronized effortlessly with automatic background syncing or push notifications, so new emails arrive instantly without draining your battery. Choose the method that works best for you.

Search powerfully across your messages using local search on your device or server-side search across your email provider's servers. Find what you need in seconds.

Secure sensitive emails with OpenPGP email encryption using the PGP/MIME standard. Install OpenKeychain: Easy PGP alongside K-9 Mail to encrypt and decrypt messages with military-grade security.

K-9 Mail is community-developed and part of the Thunderbird family, meaning continuous improvement driven by real users, not corporate interests. The source code is open for anyone to audit, modify, or contribute to. Whether you're a developer, designer, translator, or simply passionate about open source, your help makes this app better for everyone.

Choose K-9 Mail for an email experience built on trust, transparency, and genuine user control.