Courier Mail Server vs Postal
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?
Courier Mail Server
Integrated mail server with IMAP, POP, and webmail
VS
Postal
Complete mail delivery platform for outgoing email
| Feature | Courier Mail Server | Postal |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | GPL-3.0 | MIT |
| Language | C | Ruby |
| Setup difficulty | Hard | Hard |
| Min. RAM | 512 MB | 2,048 MB |
| Deployment | bare-metal, source | docker, bare-metal |
| GitHub stars | ★ 13 | ★ 16,724 |
| First released | 2000 | 2017 |
| Replaces | Microsoft Exchange | SendGrid, Mailgun, Postmark |
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
Frequently asked questions
Is Courier Mail Server or Postal better?
Neither is universally better. Postal has the larger community; both share a hard setup difficulty, so the decision comes down to features and licensing.
Are Courier Mail Server and Postal free and open-source?
Yes. Courier Mail Server is licensed under GPL-3.0 and Postal under MIT. Both can be self-hosted at no software cost.
Can I run Courier Mail Server and Postal with Docker?
Courier Mail Server: check the project docs for container support. Postal: yes.