Zimbra Collaboration Suite - Open Source Edition

Zimbra is a client and server platform for next-generation messaging and collaboration.

It provides administrators and their end users innovative features that solve the challenges faced by organizations using today's legacy communications infrastructure. Key advantages include compatibility with Windows, Mac, and Linux desktop environments; better scalability and ease of maintenance; plus flexibility to integrate other applications as web services in our AJAX web client.

The Zimbra Collaboration Suite (ZCS) Open Source Edition is available for your download free of charge. You are welcome to use, modify, and redistribute ZCS Open Source Edition free of charge, provided you do so according to the terms of the appropriate License.

ZCS Network Edition has additional benefits and is available for administrators to download and try for free.

We welcome all Open Source Edition users to join the Zimbra Community, and invite you to share contributions of bug-fixes, enhancements, or other modifications with Zimbra for consideration for inclusion in Zimbra. A good first step is join the Zimbra Forums and learn more about becoming a Zimbra contributor.


  • Developer Zone - Do you have an idea for the next great innovation in collaboration? Visit our developer zone for ideas and tools to get you started.
  • Forums - Subscribe to forums, ask questions and participate in the Zimbra community.
  • Blog - Read the latest thoughts from the Zimbra team on how to improve collaboration and messaging.
  • Contribute - Do you have an idea for improving Zimbra? Have you developed a great mash-up? Zimbra is excited to take contributions that advance the quality and innovation of collaboration platforms like ZCS.
  • Third-party open source projects - The Zimbra Project leverages other leading open source technologies such as Linux, MySQL, Postfix, and Apache. Get the full scoop here.
  • Whitepapers - There are numerous Zimbra whitepapers that cover what's wrong with email, the architecture of ZCS, compatibility with Outlook, and so on.
  • Open source licensing - The Zimbra Collaboration Suite Open Source Edition is generally licensed under the terms of the Zimbra Public License (ZPL).