Mail-in-a-Box
Turns any Ubuntu server into a fully functional mail server with one command.
- Email Servers
- Python
- CC0-1.0
- Actively maintained
GitHub stats
- GitHub stars
- 15,435
- Forks
- 1,553
- Open issues
- 552
- Commits, last 12 months
- 20
- Last commit
- Sep 26, 2026
- Latest release
- v77Sep 26, 2026
- Created
- Aug 21, 2013
Data from the GitHub API, refreshed daily.
About Mail-in-a-Box
Turns any Ubuntu server into a fully functional mail server with one command. Mail-in-a-Box is open source under the CC0-1.0 license and written mainly in Python, so you can read the code, run it on your own hardware and keep full control of your data.
The project has 15,435 stars and 1,553 forks on GitHub, with 20 commits over the last year. It installs natively rather than through an official Docker image, so plan for a short manual setup.
Topics
- smtp
- server
Open-source alternative to
Mail-in-a-Box can replace these commercial products. Compare every option on each page.
Repository preview
Similar apps
More apps like Mail-in-a-Box
Other projects in Email Servers, ranked by GitHub stars.
docker-mailserver
docker-mailserver/docker-mailserver
Production-ready fullstack but simple mail server (SMTP, IMAP, LDAP, Antispam, Antivirus, etc.) running inside a container. Only configuration files, no SQL database.
Email ServersShellDockerPostal
postalserver/postal
Complete and fully featured mail server for use by websites & web servers.
Email ServersRubyDockerStalwart Mail Server
stalwartlabs/stalwart
All-in-one mail server with JMAP, IMAP4, and SMTP support and a wide range of modern features.
Email ServersRustDockerMailcow
mailcow/mailcow-dockerized
Mail server suite based on Dovecot, Postfix and other open source software, that provides a modern Web UI for administration.
Email ServersJavaScriptDockerMailu
Mailu/Mailu
Simple yet full-featured mail server as a set of Docker images.
Email ServersPythonDockerRoundcube
roundcube/roundcubemail
Browser-based IMAP client with an application-like user interface.
Email ServersPHP
What is Mail-in-a-Box?
Mail-in-a-Box is a free, open-source app you can host on your own server, listed in our Email Servers category. Turns any Ubuntu server into a fully functional mail server with one command. The source code lives at github.com/mail-in-a-box/mailinabox, where it has 15,435 stars.
Is Mail-in-a-Box free and open source?
Yes. Mail-in-a-Box is open-source software released under the CC0-1.0 license, so you can self-host it at no cost. You only pay for the server it runs on, and some projects also offer an optional paid cloud plan.
Can I run Mail-in-a-Box with Docker?
Mail-in-a-Box does not list an official Docker image. It installs natively (Shell), so follow the install steps in its README or look for a community-maintained container.
What are the best alternatives to Mail-in-a-Box?
Popular open-source alternatives to Mail-in-a-Box include docker-mailserver, Postal and Stalwart Mail Server. Mail-in-a-Box itself is a self-hosted alternative to Gmail.
Is Mail-in-a-Box actively maintained?
The most recent commit to Mail-in-a-Box was on Sep 26, 2026 with 20 commits in the past twelve months. The latest release is v77, published Sep 26, 2026. Check the open issues on GitHub to gauge how quickly maintainers respond.