Mail-in-a-Box vs Postal
| Tagline | Turn any Ubuntu VPS into a complete, self-hosted mail server in one command | Self-hosted mail delivery platform, a SendGrid/Mailgun alternative |
| Category | Email & Newsletters | Email & Newsletters |
| Replaces | Gmail / Google Workspace, Mailchimp, SendGrid | SendGrid |
| GitHub stars | 15k | 17k |
| Language | Shell | Ruby |
| License | CC0-1.0 | MIT |
| Self-host difficulty | 2/5 Easy | 4/5 Involved |
| Deploy options | Manual | Docker Docker Compose Manual |
| Managed hosting | ||
| Last updated | 25 days ago | 9 days ago |
| View repo | View repo |
Where each falls short
The honest trade-offs — what you give up with each, versus the proprietary tools they replace.
Mail-in-a-Box
- Requires a dedicated Ubuntu VPS with a clean IP reputation; shared hosting is not supported
- No built-in bulk mailing or newsletter campaign tools
- Limited horizontal scalability; single-server architecture only
- Webmail (Roundcube) is functional but far less polished than Gmail's UI
Postal
- You are responsible for IP reputation, warmup, and deliverability
- Requires MariaDB, RabbitMQ, and DNS/DKIM configuration to run
- No marketing-campaign UI — it is a delivery engine, not a newsletter builder
- Less hand-holding than managed providers for spam/blocklist issues
Bottom line
Choose Mail-in-a-Box if you want the lower-effort setup; choose Postal for the larger community and ecosystem. Postal has seen more recent development. Open each guide below for deploy steps and the full feature gap.
Mail-in-a-Box
Turn any Ubuntu VPS into a complete, self-hosted mail server in one command