Cyrus IMAP vs Postfix

A side-by-side comparison of two self-hosted mail servers options — licensing, setup difficulty, resource needs, and what each one replaces.

Not the right match-up?
FeatureCyrus IMAPPostfix
CategoryMail ServersMail Servers
LicenseBSD-3-ClauseIPL-1.0
LanguageCC
Setup difficultyHardHard
Min. RAM1,024 MB128 MB
Deploymentbare-metal, sourcedocker, bare-metal, source
GitHub stars★ 641★ 563
First released19941998
ReplacesMicrosoft ExchangeMicrosoft Exchange

Why pick each one

Choose Cyrus IMAP if…

  • Released under the BSD-3-Clause license
  • Written in C
Cyrus IMAP details

Choose Postfix if…

  • Battle-tested and stable
  • Extensive documentation
Postfix details

Frequently asked questions

Is Cyrus IMAP or Postfix better?

Neither is universally better. Cyrus IMAP has the larger community; both share a hard setup difficulty, so the decision comes down to features and licensing.

Are Cyrus IMAP and Postfix free and open-source?

Yes. Cyrus IMAP is licensed under BSD-3-Clause and Postfix under IPL-1.0. Both can be self-hosted at no software cost.

Can I run Cyrus IMAP and Postfix with Docker?

Cyrus IMAP: check the project docs for container support. Postfix: yes.

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