The Best 16 AtMail Open Alternatives

  • Horde

    Horde Groupware is a free, enterprise ready, browser based collaboration suite. Users can manage and share calendars, contacts, tasks and notes with the standards compliant components from the Horde Project.

    Free Open Source Web Self-Hosted

  • Squirrelmail

    SquirrelMail is a standards-based webmail package written in PHP. It includes built-in pure PHP support for the IMAP and SMTP protocols, and all pages render in pure HTML 4.

    Free Open Source Self-Hosted PHP

  • Webmail Lite

    Open Source WebMail Lite is a free community edition of full-featured WebMail Pro server application intended for users who need a clean and simple web mail application, which is fast and easy to use.

    Free Open Source Web Self-Hosted

  • NaSMail

    NaSMail is a standards-based webmail package written in PHP. It includes built-in pure PHP support for the IMAP and SMTP protocols, and all pages render in HTML 4.01...

    Free Open Source Web

  • NOCC

    NOCC is a webmail client written in PHP. It provides webmail access to IMAP and POP3 accounts.

    Free Open Source Web

  • Sendmail

    Sendmail is a general purpose internetwork email routing facility that supports many kinds of transfer and delivery methods, including the Simple Mail Transfer Protocol (SMTP) used for email transport over the Internet.

    Free Open Source Mac OS X Linux

  • Flaskmail

    Easy to use and secure email hosting solution for any available domain name, including your own.

    Commercial Web

  • Microsoft SMTP Server

    Configure SMTP e-mail in IIS when you want to deliver e-mail messages from your site. Mail can be delivered immediately or it can be delivered to a file location on disk...

    Commercial Windows

  • PowerMTA

    Email gateway application (SMTP server) that makes it easy for senders to adopt the latest authentication specifications ( SPF and DKIM) to comply with changing ISP...

    Commercial Windows Linux Self-Hosted