Courier Mail Server vs mailcow
A side-by-side comparison of two self-hosted mail servers options — licensing, setup difficulty, resource needs, and what each one replaces.
mailcow
Dockerized full-stack mail server suite
| Feature | Courier Mail Server | mailcow |
|---|---|---|
| Deploy effort | Read-the-docs project | Under-an-hour setup |
| Health score | 62 · Good | 94 · Excellent |
| Category | Mail Servers | Mail Servers |
| License | GPL-3.0 | GPL-3.0 |
| Language | C | JavaScript |
| Setup difficulty | Hard | Medium |
| Min. RAM | 512 MB | 6,144 MB |
| Deployment | bare-metal, source | docker |
| GitHub stars | ★ 13 | ★ 13,498 |
| First released | 2000 | 2016 |
| Replaces | Microsoft Exchange | Microsoft Exchange, Google Workspace |
What are Courier Mail Server and mailcow?
Courier Mail Server
Courier is an integrated mail server suite that combines an MTA with IMAP, POP3, ESMTP, and webmail components. It provides a complete mail system from a single coordinated project.
- Integrated MTA and IMAP
- Built-in webmail
- Maildir storage
- LDAP authentication
mailcow
mailcow is a complete, Docker-based mail server solution that bundles Postfix, Dovecot, Rspamd, SOGo, and a modern web UI. It makes running a full-featured mail server with antispam and webmail straightforward.
- Complete Docker mail stack
- Rspamd antispam built in
- SOGo webmail and ActiveSync
- Modern management UI with API
Courier Mail Server vs mailcow: key differences
Courier Mail Server is written in C, while mailcow is built with JavaScript. Courier Mail Server is the lighter option, starting around 512 MB of RAM against 6,144 MB for mailcow. Courier Mail Server is the more established project (first released 2000), while mailcow arrived in 2016. Mailcow has the considerably larger community, at 13,498 GitHub stars versus 13. Mailcow lists first-class Docker deployment; Courier Mail Server does not.
Why pick each one
Choose Courier Mail Server if…
- Released under the GPL-3.0 license
- Written in C
- Lightweight — runs in 512 MB RAM
Choose mailcow if…
- All components preconfigured
- Active community
Watch out for
- Substantial RAM requirements
- Many containers to manage
Frequently asked questions
Is Courier Mail Server or mailcow better?
mailcow is the stronger all-round pick: it has both the larger community and the simpler medium setup. Consider Courier Mail Server if its specific feature set fits your needs better.
Are Courier Mail Server and mailcow free and open-source?
Yes. Courier Mail Server is licensed under GPL-3.0 and mailcow under GPL-3.0. Both can be self-hosted at no software cost.
Can I run Courier Mail Server and mailcow with Docker?
Courier Mail Server: check the project docs for container support. mailcow: yes.
Which is lighter on resources, Courier Mail Server or mailcow?
Courier Mail Server has the smaller minimum footprint at 512 MB of RAM, compared to about 6,144 MB for mailcow. Real-world usage depends on library size, user count, and enabled features.