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Email · 10 alternatives

Instead of K-9 Mail, try one of these 10.

Every alternative is lined up against K-9 Mail on what people actually switch for: price, open source, self-hosting, offline use and platforms. K-9 Mail sits in the first row, so you can see what you give up.

Show onlySorted by likes · 10 of 10
Alternative
Price
Open source
Self-host
Offline
Platforms
K-9 MailWhat you have now
Open-source Android client for multiple mail accounts.
PriceFree
Open sourceYes
Self-hostNo
OfflineYes
Platforms
Android
Thunderbird#1
Free, open-source desktop email client from Mozilla.
PriceFree
Open sourceYes
Self-hostNo
OfflineYes
Platforms
Win · Mac · Linux
Spark#2
Smart inbox that filters noise and groups by sender.
PriceFreemium
premium $5/mo
Open sourceNo
Self-hostNo
OfflinePartial
Platforms
Web · Mac · Win · iOS · Android
Outlook.com#3
Microsoft's free webmail and calendar service.
PriceFreemium
Open sourceNo
Self-hostNo
OfflineNo
Platforms
Web
Evolution#4
GNOME mail, calendar and contacts suite for Linux.
PriceFree
Open sourceYes
Self-hostNo
OfflineYes
Platforms
Linux
Mailspring#5
Fast desktop mail client with unified inbox and tracking.
PriceFreemium
Open sourceYes
Self-hostNo
OfflineYes
Platforms
Win · Mac · Linux
Betterbird#6
Thunderbird fork adding fixes and extra features.
PriceFree
Open sourceYes
Self-hostNo
OfflineYes
Platforms
Win · Mac · Linux
FairEmail#7
Privacy-first Android mail app with strong encryption options.
PriceFreemium
Open sourceYes
Self-hostNo
OfflineYes
Platforms
Android
BlueMail#8
Mobile-first unified inbox covering all your accounts.
PriceFree
Open sourceNo
Self-hostNo
OfflineYes
Platforms
Win · Mac · Linux · Android · iOS
Canary Mail#9
Secure mail app with AI help and read receipts.
PriceFreemium
Open sourceNo
Self-hostNo
OfflineYes
Platforms
Win · Mac · Android · iOS
Infomaniak kMail#10
Swiss hosted mail with collaboration tools and ethical hosting.
PriceFreemium
Open sourceYes
Self-hostNo
OfflinePartial
Platforms
Web · iOS · Android

How to read this. “Yes” means fully supported by the maker. “Partial” means it works with caveats. Likes reflect community popularity; vendors can’t pay for them or for placement. How we compare.

K-9 Mail alternatives at a glance

K-9 Mail is a free email app. We compared 10 alternatives: 6 are open source, 4 are completely free, 0 can be self-hosted and 7 work fully offline. The most popular is Thunderbird, with 1.7k likes.

Most liked overallThunderbird

Free, open-source desktop email client from Mozilla.

Free · Open source · Works offline
Best free optionEvolution

GNOME mail, calendar and contacts suite for Linux.

Free · Open source · Works offline
Best open-source optionMailspring

Fast desktop mail client with unified inbox and tracking.

Freemium · Open source · Works offline
Best for offline useBetterbird

Thunderbird fork adding fixes and extra features.

Free · Open source · Works offline

More email apps

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