Citadel vs SOGo

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

Not the right match-up?
FeatureCitadelSOGo
CategoryGroupwareGroupware
LicenseGPL-3.0GPL-2.0
LanguageCObjective-C
Setup difficultyMediumHard
Min. RAM512 MB1,024 MB
Deploymentbare-metal, sourcedocker, bare-metal
GitHub stars★ 100★ 2,143
First released19872009
ReplacesMicrosoft Exchange, Microsoft 365Microsoft Exchange, Microsoft 365

Why pick each one

Choose Citadel if…

  • Single-package setup
  • Low resource needs
Citadel details

Choose SOGo if…

  • Strong Outlook compatibility
  • Scales to many users
SOGo details

Frequently asked questions

Is Citadel or SOGo better?

Neither is universally better. SOGo has the larger community, while Citadel is simpler to set up (medium difficulty). Choose based on the comparison table above and your own setup.

Are Citadel and SOGo free and open-source?

Yes. Citadel is licensed under GPL-3.0 and SOGo under GPL-2.0. Both can be self-hosted at no software cost.

Can I run Citadel and SOGo with Docker?

Citadel: check the project docs for container support. SOGo: yes.

Related comparisons