Browse free open source Email Clients and projects for Linux below. Use the toggles on the left to filter open source Email Clients by OS, license, language, programming language, and project status.

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  • 1
    SquirrelMail
    SquirrelMail is a PHP-based Web email client. It includes built-in pure PHP support for IMAP and SMTP, and renders all pages in pure HTML 4.0 for maximum compatibility across browsers. It has strong MIME support and a flexible plugin system.
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    Downloads: 392 This Week
    Last Update:
    See Project
  • 2
    threadkey

    threadkey

    Add keyboard shortcuts to switch between different thread views

    Strike the 'T' key to sort messages by thread, strike the 'U' key to sort unthreaded again, just like the 'G' key switches to Grouped By Sort view.
    Downloads: 105 This Week
    Last Update:
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  • 3
    Columba
    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.
    Downloads: 29 This Week
    Last Update:
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  • 4
    NOCC
    NOCC is a simple and fast Webmail client which can handle POP3 and IMAP mailboxes and sends email via SMTP. It is written with PHP, has low requirements (no database, frames). Features multi-language support, MIME attachments, displays HTML messages. The installation guide comes with the source code: https://sourceforge.net/p/nocc/code/HEAD/tree/trunk/webmail/docs/INSTALL If you encounter problems or bugs you can always try the current HEAD version: https://sourceforge.net/p/nocc/code/HEAD/tarball?path= Questions, bug reports or support requests are very welcome: https://sourceforge.net/p/nocc/_list/tickets Alternative source code repository: https://github.com/oheil/NOCC
    Downloads: 10 This Week
    Last Update:
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  • 5
    Claws Mail
    Claws Mail is a GTK+ based, lightweight, and fast e-mail client and newsreader. Supports POP3, APOP, IMAP, SMTP, SMTP AUTH, NNTP, LDAP, multiple accounts, spell-checking, addressbook, SSL, GPG, filtering, i18n, & more. It is further extended by plugins.
    Downloads: 19 This Week
    Last Update:
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  • 6
    AfterLogic WebMail Lite 7
    AfterLogic WebMail Lite PHP is a free AJAX webmail application. Users can receive, view, manage, compose, and send email through web interface (IMAP and SMTP supported). Source code included.
    Downloads: 2 This Week
    Last Update:
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  • 7
    Hastymail
    Hastymail is a fast, secure, rfc-compliant, cross-platform IMAP/SMTP client application written in PHP providing a clean web interface for sending and reading E-mail. This version of Hastymail is no longer being developed. We are now working on a new version, Hastymail 3, AKA, "Cypht". http://cypht.org
    Downloads: 1 This Week
    Last Update:
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  • 8
    RainLoop Webmail (PHP)

    RainLoop Webmail (PHP)

    Simple, modern & fast web-based email client

    Modest system requirements, decent performance, simple installation and upgrade, no database required - all these make RainLoop Webmail a perfect choice for your email solution.
    Downloads: 2 This Week
    Last Update:
    See Project
  • 9
    mailredirect

    mailredirect

    Allow to redirect (a.k.a. "remail") mail messages to other recipients

    The Mailredirect extension for Mozilla Thunderbird and Mozilla SeaMonkey adds the ability to redirect one or more email messages to one or more recipients. The feature of email redirecting is also known as remailing or resending. The extension is an answer for https://bugzil.la/12916
    Downloads: 1 This Week
    Last Update:
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  • 10
    Archive This for Thunderbird
    "Archive This" is an add-on for the Thunderbird email client that provides shortcuts for filing messages into folders rapidly and efficiently.
    Downloads: 0 This Week
    Last Update:
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  • 11
    EGroupware Enterprise Collaboration
    EGroupware has moved to Github, please find all our downloads there: https://github.com/EGroupware/egroupware/releases EGroupware is a multi-user, web-based groupware suite. Currently available modules include: email, addressbook, calendar, infolog (notes, to-do's, phone calls), content management, wiki, project management, tracker, timesheet, knowledge base, CalDAV/CardDAV
    Downloads: 0 This Week
    Last Update:
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  • 12
    Webmail with support for MIME mail, address book, plugin system, differrent themes and languages. Runs on PHP, MySQL and connects to IMAP servers.
    Downloads: 0 This Week
    Last Update:
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  • 13
    A plugin for the MacOS X Mail application that adds the ability to fetch mail stored on a httpmail (Hotmail) server
    Downloads: 0 This Week
    Last Update:
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  • 14
    NOTICE: Keep in mind that POP3ye is alpha software and by definition it is a long way from finished. POP3ye is a fully featured web-based e-mail client written in Object Oriented PHP 5. It ony supports the POP3 protocol.
    Downloads: 0 This Week
    Last Update:
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  • 15
    Roundcube Webmail

    Roundcube Webmail

    Free and open source webmail software

    Roundcube Webmail is a browser-based, multilingual IMAP client with an application-like user interface. Roundcube provides the full functionality you'd expect from an email client, including MIME support, address book, folder manipulation, message searching, and spell check. Roundcube is written in PHP and JavaScript.
    Downloads: 0 This Week
    Last Update:
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  • 16
    Shell project for a better shell on UNIX like systems Improved.
    Downloads: 0 This Week
    Last Update:
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  • 17
    Twiggi is a web-based groupware solution for Linux. It includes the ability to securely share information with co-workers either individually or via assigned groups. Twiggi features the following modules: IMAP webmail, calendar, todo list and more...
    Downloads: 0 This Week
    Last Update:
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  • 18
    vteddy

    vteddy

    Business webmail modular application with mobile client

    The most complete Business Webmail with Mobile client application for companies of all sizes. All the core functions for business like calendaring and integrated webmail, plus the capability of converting emails into business objects such as: quotes, invoices, marketing stuff, customer requests, project management and more. A simple way to have a unique flow of information from email request from customers to invoices!
You only have to choose which modules you want to activate and is done!
Built with PHP, loves MySQL but runs also on SQL Server and Oracle.
    Downloads: 0 This Week
    Last Update:
    See Project
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