97.2K reviews
Content rating
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About this app

K-9 Mail is an open source email client that works with basically every email provider.


* supports multiple accounts
* Unified Inbox
* privacy-friendly (no tracking whatsoever, only connects to your email provider)
* automatic background synchronization or push notifications
* local and server-side search
* OpenPGP email encryption (PGP/MIME)

Install the app "OpenKeychain: Easy PGP" to encrypt/decrypt your emails using OpenPGP.


If you're having trouble with K-9 Mail, ask for help in our support forum at https://forum.k9mail.app

Want to help?

K-9 Mail is a community developed project. If you're interested in helping to improve the app, please join us! You can find our bug tracker, source code, and wiki at https://github.com/k9mail/k-9
We're always happy to welcome new developers, designers, documenters, translators, bug triagers and friends.
Updated on
May 12, 2023

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
This app may share these data types with third parties
Personal info
No data collected
Learn more about how developers declare collection
Data is encrypted in transit
Data can’t be deleted

Ratings and reviews

92.2K reviews
Mayer Kurcfeld
May 21, 2023
I'm a Longtime K9 User and love the newest version! Just one requested tweak... In Default/Light mode, after reading an email, the contrast between the letters and grey background is very slight to the point that it is not easy to read the words when scrolling for a specific, previously read email. Can you lighten a bit of the grey background for more contrast and/or is there a way to do it ourselves within the app? Keep up the good work! 👏🏻🧔🏻
2 people found this review helpful
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Bob Mertz (bobkmertz)
April 9, 2023
What Thunderbird has done to this app is an absolute crime. It's no longer just the UI and cosmetic issues but the app is now stupidly slow and constantly crashes. This was once the leanest, fastest, and easy to use app for someone with multiple email accounts and now it's borderline useless. I wish companies could just realize when they have something great rather than try to make it something that it's users never wanted in the first place.
157 people found this review helpful
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Sergio Lopez
February 23, 2023
Don't see the issues others have raised. Not perfect, but as simple or complicated as you want it to be. Defaults are not ideal but it's way easier to quickly adjust with a quick look at the settings than before. Less clunky and more functional than Gmail. Worth switching to for only a slightly worse learning curve. Seems to suffer in some technological edge cases, but none in my own experience -- read reviews to see.
21 people found this review helpful
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What's new

Changed primary action in message view header from "reply all" to "reply"