Postal vs OfflineIMAP
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
OfflineIMAP
Synchronize IMAP mailboxes to local Maildir
| Feature | Postal | OfflineIMAP |
|---|---|---|
| Category | Mail Servers | Mail Servers |
| License | MIT | GPL-2.0 |
| Language | Ruby | Python |
| Setup difficulty | Hard | Medium |
| Min. RAM | 2,048 MB | 64 MB |
| Deployment | docker, bare-metal | binary, source |
| GitHub stars | ★ 16,724 | ★ 631 |
| First released | 2017 | 2002 |
| Replaces | SendGrid, Mailgun, Postmark | Outlook offline mode |
Why pick each one
Choose OfflineIMAP if…
- Released under the GPL-2.0 license
- Written in Python
- Tiny footprint — runs in 64 MB RAM
Frequently asked questions
Is Postal or OfflineIMAP better?
Neither is universally better. Postal has the larger community, while OfflineIMAP is simpler to set up (medium difficulty). Choose based on the comparison table above and your own setup.
Are Postal and OfflineIMAP free and open-source?
Yes. Postal is licensed under MIT and OfflineIMAP under GPL-2.0. Both can be self-hosted at no software cost.
Can I run Postal and OfflineIMAP with Docker?
Postal: yes. OfflineIMAP: check the project docs for container support.