Mozilla SeaMonkey: Open Source Email Program

Mozilla SeaMonkey running on Windows
What We Like
  • Mozilla SeaMonkey comes with precise spam filtering and lets you organize mail with tags


  • Smart features and defaults make Mozilla secure and privacy-conscious


  • Mozilla offers great support for HTML formatting and a powerful message editor in general


What We Don't Like
  • Mozilla SeaMonkey does not include fast, index-based search


  • The Bayesian spam filter in Mozilla is resource hungry and slow


  • Mozilla cannot filter outgoing mail and lacks sophisticated message templates


Mozilla is not only a great browser but also a fully-featured and powerful email client. It comes with great security and privacy, highly effective spam filtering and is still easy and fun to use.

Description of Mozilla SeaMonkey

  • Mozilla manages multiple POP and IMAP email accounts.
  • Mozilla sports flexible filters and message tags to sort and organize messages.
  • Search toolbar, advanced search, and message views make it easy to find mail in Mozilla.
  • Mozilla's highly effective Bayesian spam filtering moves junk to a special folder automatically.
  • Great security and privacy: cookies, remote images, JavaScript can be disabled, no known exploits.
  • Mozilla supports TLS/SSL connections and S/MIME or PGP/MIME (via plug-in) message encryption.
  • Richly formatted HTML messages can be displayed as full HTML, simple HTML or plain text.
  • Mozilla comes with great HTML editing, but sending proper plain text emails is easy, too.
  • The fully-featured Mozilla address book supports vCards and Palm synchronization.
  • Mozilla supports Windows 9x/ME/2000/3/XP/Vista or higher, Mac OS X and Linux.

Mozilla SeaMonkey​ Review

Maybe you've read somewhere that Mozilla is "not for end-users." Don't believe it. It was never true, and now it is less than ever. Getting, installing and using Mozilla is a snap, and there's so much about it to enjoy that you'll soon learn to love Mozilla, the email client.

Mozilla is a fully-featured email program with flexible filters, good IMAP support, powerful searching, strong HTML and plain text support, really useful free-form tags and views for prioritizing and organizing mail, S/MIME encryption and — probably most importantly — many great features that help maintain computer security and personal privacy.

You can turn off JavaScript and remote images as well as cookies and still enjoy a comfortable email experience. That's also thanks to great spam filtering. After some training, Mozilla's Bayesian spam filter works wonders with very few false positives. What Mozilla still lacks: outgoing mail filters and flexible message templates.