Postal vs EmailRelay
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?
Postal
Complete mail delivery platform for outgoing email
VS
EmailRelay
A small and easy to configure SMTP and POP3 server for Windows and
| Feature | Postal | EmailRelay |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | MIT | GPL-3.0 |
| Language | Ruby | C++ |
| Setup difficulty | Hard | Medium |
| Min. RAM | 2,048 MB | 512 MB |
| Deployment | docker, bare-metal | bare-metal |
| GitHub stars | ★ 16,724 | — |
| First released | 2017 | 2020 |
| Replaces | SendGrid, Mailgun, Postmark | — |
Why pick each one
Choose EmailRelay if…
- Released under the GPL-3.0 license
- Written in C++
- Lightweight — runs in 512 MB RAM
Frequently asked questions
Is Postal or EmailRelay better?
Neither is universally better. Postal has the larger community, while EmailRelay is simpler to set up (medium difficulty). Choose based on the comparison table above and your own setup.
Are Postal and EmailRelay free and open-source?
Yes. Postal is licensed under MIT and EmailRelay under GPL-3.0. Both can be self-hosted at no software cost.
Can I run Postal and EmailRelay with Docker?
Postal: yes. EmailRelay: check the project docs for container support.