FossaMail Alternatives

FossaMail is described as 'Open Source, Mozilla Thunderbird -based mail, news and chat client for Windows and Linux, brought to you by the Pale Moon developers' and is a Email Client in the office & productivity category. There are more than 10 alternatives to FossaMail for a variety of platforms, including Windows, Mac, Linux, iPhone and Android apps. The best FossaMail alternative is Thunderbird, which is both free and Open Source. Other great apps like FossaMail are K-9 Mail, Spark Mail, eM Client and Claws Mail.

FossaMail alternatives are mainly Email Clients but may also be Calendar Apps. Filter by these if you want a narrower list of alternatives or looking for a specific functionality of FossaMail.

FossaMail alternatives page was last updated

FossaMail

Free • Open Source
Email Client

FossaMail is an Open Source, Mozilla Thunderbird -based mail, news and chat client for...

More about FossaMail

Mailbird
Sponsored
Paid • Proprietary
Email Client
Windows
66 Mailbird alternatives
Mailbird helps individuals and businesses manage emails in one place. This allows you to simplify your workflows. Therefore, spend more time on important tasks. Moreover, 9 in 10 of our customers describe our interface as “intuitive” and beautiful.
Thunderbird
Is this is a good alternative?
Yes
No
Free • Open Source
Email Client
Calendar App
Mac
Windows
Linux
BSD
AppImageHub
Snapcraft
Flathub
PortableApps.com
Haiku
Homebrew
Chocolatey
95 Thunderbird alternatives
Thunderbird is a free, open source, cross-platform e-mail, news and instant messaging client. The project strategy is modeled after Mozilla Firefox.
- - Thunderbird is the most popular Windows, Mac & Linux alternative to FossaMail.
- - Thunderbird is the most popular Open Source & free alternative to FossaMail.
Suggest and vote on features
Thunderbird Features
1. Extensible by Plugins/ExtensionsThunderbird can be extended with add-ons, plugins and extensions.
2. Multiple Account supportThunderbird support multiple accounts without the need to logout and login
3. Calendar IntegrationThunderbird lets you sync your tasks and events with your calendar application.
4. Email OrganizerThunderbird allows you to take control of your inbox by filtering and control tools.
5. Dark ModeThunderbird supports dark mode for comfortable usage in low light conditions.
6. OpenPGPThunderbird supports OpenPGP, a standard of PGP encryption that is open-source for public use.
7. GPG EncryptionThunderbird supports GPG (aka GnuPG) for encryption of things like emails, messages, files, etc.
8. PortableThunderbird can be used from a USB stick or similar with no prior installation.
9. Import/Export OPML FeedsImport and export your feed subscriptions into OPML format with Thunderbird.
IMAP Support
SMTP Support
FOSS
Add-ons
Built-in RSS reader
POP3 Support
Graphical User Interface
Intuitive
Integrated Web Browser
Customizable
K-9 Mail
Is this is a good alternative?
Yes
No
Free • Open Source
Email Client
Android
Android Tablet
F-Droid
46 K-9 Mail alternatives
K-9 is an open source email client for Android with multi-folder sync, email signatures, Bcc-to-self, return-address configuration, keyboard shortcuts, Exchange Support, message flagging, IMAP deletes, saving attachments, configurable notifications and more.
- - K-9 Mail is the most popular Android & Android Tablet alternative to FossaMail.
Suggest and vote on features
K-9 Mail Features
1. Ad-freeK-9 Mail doesn't contain any form of external advertising.
2. Multiple Account supportK-9 Mail support multiple accounts without the need to logout and login
3. Privacy focusedK-9 Mail is considered a privacy friendly alternative.
4. PGP EncryptionK-9 Mail supports PGP, an encryption system used for sending encrypted emails and files.
5. No TrackingK-9 Mail will not track you or use your personal data.
6. End-to-End EncryptionK-9 Mail has E2E Encryption, for entire or parts of the app.
IMAP Support
Configurable
POP3 Support
One view multiple accounts
Custom notifications
Contacts
Exchange
Header sorting
Spark Mail
Is this is a good alternative?
Yes
No
Freemium • Proprietary
Email Client
Calendar App
Mac
Windows
Android
iPhone
iPad
Apple Watch
60 Spark Mail alternatives
E-mail app with all the great features: swipes (long/short), snooze, add (multiple) attachments from the cloud, support for various e-mail services and more.
- - Spark Mail is the most popular iPhone & iPad alternative to FossaMail.
Suggest and vote on features
Spark Mail Features
1. Multiple Account supportSpark Mail support multiple accounts without the need to logout and login
2. Email SchedulingYou can schedule a marketing, sales, or personal email for a time in the future with Spark Mail.
3. Calendar IntegrationSpark Mail lets you sync your tasks and events with your calendar application.
4. Cloud SyncSync your data (notes, documents, bookmarks, etc.) across your different devices and to the cloud.
5. Email OrganizerSpark Mail allows you to take control of your inbox by filtering and control tools.
6. Dark ModeSpark Mail supports dark mode for comfortable usage in low light conditions.
7. Unified inboxView e-mails (or similar) from all accounts in one unified view with Spark Mail.
8. Works OfflineSpark Mail can be used without the need to connect to the internet.
9. Calendar ViewSpark Mail has a built-in calendar view to have a clear overview of your content over time.
Snooze Mail
Sorting by folder
Ad-free
Sync with Google Calendar
Exchange
Postpone email reception
AI-Powered
eM Client
Is this is a good alternative?
Yes
No
Freemium • Proprietary
Email Client
Calendar App
Mac
Windows
65 eM Client alternatives
eM Client is a full featured e-mail client with a modern and easy to use interface. eM Client also offers calendar, tasks, contacts, notes and chat.
Suggest and vote on features
eM Client Features
1. Calendar IntegrationeM Client lets you sync your tasks and events with your calendar application.
2. Multiple Account supporteM Client support multiple accounts without the need to logout and login
3. PGP EncryptioneM Client supports PGP, an encryption system used for sending encrypted emails and files.
4. Dark ModeeM Client supports dark mode for comfortable usage in low light conditions.
5. Unified inboxView e-mails (or similar) from all accounts in one unified view with eM Client.
6. Cloud SyncSync your data (notes, documents, bookmarks, etc.) across your different devices and to the cloud.
7. Email OrganizereM Client allows you to take control of your inbox by filtering and control tools.
8. Sync with Google CalendareM Client can be synchronized with Google Calendar
9. Automatic BackupeM Client will automatically back up your data periodically.
IMAP Support
Exchange
CardDAV Support
CalDAV Support
Contacts
Gmail integration
Calendar Sync
POP3 Support
Email preview
Sync Contacts
Claws Mail
Is this is a good alternative?
Yes
No
Free • Open Source
Email Client
Calendar App
Windows
Linux
BSD
84 Claws Mail alternatives
Claws Mail is an email client (and news reader), based on GTK+, featuring

Quick response Graceful, and sophisticated interface Easy configuration, intuitive operation Abundant features Extensibility Robustness and stability.
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Claws Mail Features
1. LightweightClaws Mail consumes less device resources compared to similar apps.
2. Extensible by Plugins/ExtensionsClaws Mail can be extended with add-ons, plugins and extensions.
3. Multiple Account supportClaws Mail support multiple accounts without the need to logout and login
4. No registration requiredYou can use most of the features in Claws Mail without registration.
5. Spam FilterClaws Mail can detect unsolicited, unwanted and virus-infected emails, calls, files, etc.
6. Privacy focusedClaws Mail is considered a privacy friendly alternative.
7. Works OfflineClaws Mail can be used without the need to connect to the internet.
8. Calendar IntegrationClaws Mail lets you sync your tasks and events with your calendar application.
9. PortableClaws Mail can be used from a USB stick or similar with no prior installation.
IMAP Support
Customizable
Ad-free
GPG Encryption
Import/Export OPML Feeds
End-to-End Encryption
Built-in RSS reader
Integrated Email Client
Multiple languages
Content Filtering
Mailbird
Is this is a good alternative?
Yes
No
Paid • Proprietary
Email Client
Windows
66 Mailbird alternatives
Mailbird helps individuals and businesses manage emails in one place. This allows you to simplify your workflows. Therefore, spend more time on important tasks. Moreover, 9 in 10 of our customers describe our interface as “intuitive” and beautiful.
- - Mailbird is the most popular commercial alternative to FossaMail.
Suggest and vote on features
Mailbird Features
1. Dark ModeMailbird supports dark mode for comfortable usage in low light conditions.
2. Unified inboxView e-mails (or similar) from all accounts in one unified view with Mailbird.
3. Multiple Account supportMailbird support multiple accounts without the need to logout and login
4. Email template editorMailbird offers pre-defined email layouts so you can add content or customize your own templates.
5. Email OrganizerMailbird allows you to take control of your inbox by filtering and control tools.
Clean design
Sync Contacts
Undo send
Email tracking
GSuite Integration
Slack integration
Asana integration
Unified communications
Multi Account Switching
Graphical User Interface
Postbox
Is this is a good alternative?
Yes
No
Paid • Proprietary
Email Client
Mac
Windows
71 Postbox alternatives
Postbox is an email application that helps you organize your work life and get stuff done.
Suggest and vote on features
Postbox Features
1. Multiple Account supportPostbox support multiple accounts without the need to logout and login
2. Extensible by Plugins/ExtensionsPostbox can be extended with add-ons, plugins and extensions.
Exchange
Box.com integration
Tabbed interface
Dropbox integration
IMAP Support
Built-in RSS reader
S/MIME Support
Multiple languages
Onedrive integration
Visual Programming
Airmail
Is this is a good alternative?
Yes
No
Paid • Proprietary
Email Client
Mac
iPhone
iPad
Apple Watch
69 Airmail alternatives
Airmail is a lightweight and lightning fast mail client for Mac.
Suggest and vote on features
Airmail Features
1. Multiple Account supportAirmail support multiple accounts without the need to logout and login
2. LightweightAirmail consumes less device resources compared to similar apps.
Clean design
IMAP Support
POP3 Support
Fullscreen support
Dropbox integration
Customizable
Canary Mail
Is this is a good alternative?
Yes
No
Freemium • Proprietary
Email Client
Calendar App
Mac
Windows
Android
iPhone
Android Tablet
iPad
Apple Watch
63 Canary Mail alternatives
Email, meet AI. Canary can write your emails, prioritize what needs attention, silence spam & much more. Say hello to your Inbox Copilot!
Suggest and vote on features
Canary Mail Features
1. End-to-End EncryptionCanary Mail has E2E Encryption, for entire or parts of the app.
2. Unified inboxView e-mails (or similar) from all accounts in one unified view with Canary Mail.
3. Multiple Account supportCanary Mail support multiple accounts without the need to logout and login
4. PGP EncryptionCanary Mail supports PGP, an encryption system used for sending encrypted emails and files.
5. No TrackingCanary Mail will not track you or use your personal data.
6. Dark ModeCanary Mail supports dark mode for comfortable usage in low light conditions.
7. Two-factor AuthenticationCanary Mail supports two-factor authentication (2FA).
8. Email OrganizerCanary Mail allows you to take control of your inbox by filtering and control tools.
9. Ad-freeCanary Mail doesn't contain any form of external advertising.
AI-Powered
Email tracking
Snooze Mail
Reminders
Email reminder
Gmail
Email template editor
Read receipts
Spam Filter
Calendar View
Zimbra Desktop
Is this is a good alternative?
Yes
No
Free Personal • Proprietary
Email Client
Calendar App
Mac
Windows
Linux
60 Zimbra Desktop alternatives
The free Zimbra Desktop client allows you to meld the online and offline worlds – storing and synching your email, calendar, contacts, files and documents in the cloud, yet having them locally accessible when on the road.
Suggest and vote on features
Zimbra Desktop Features
Email checker
Discontinued
From download page: "The Zimbra Desktop is no longer supported. It will reach the end of Technical Guidance October 1, 2019.".See https://www.zimbra.com/downloads/zimbra-desktop/
Columba
Is this is a good alternative?
Yes
No
Free • Open Source
Email Client
Mac
Windows
Linux
BSD
60 Columba alternatives
Columba is an email client written in Java, featuring a user-friendly graphical interface with wizards and internalionalization support. Its a powerful mail management tool with features to enhance your productivity and communication.
Columba has no features, suggest some!
Discontinued
The project is no longer developed. Last version, 1.4, released in March 2007, can be still downloaded from SourceForge.