mailcow

mailcow is a complete, Docker-based email server suite that bundles every component you need to run your own mail infrastructure into a single stack. Postfix handles the mail transfer, Dovecot the IMAP/POP delivery, Rspamd the spam filtering with auto-learning, SOGo the webmail client with CalDAV and CardDAV support, and ClamAV the antivirus scanning. You deploy the whole thing with Docker Compose, configure your DNS records, and you have a fully operational email server with a web UI for managing domains, mailboxes, and aliases.

The admin interface covers DKIM key generation, spam score management per user, a quarantine system, two-factor authentication via TOTP and Yubikey, and automatic Let’s Encrypt certificate renewal. SOGo gives users a browser-based mail client with calendar and contact sync, making this a workable replacement for Google Workspace or Microsoft 365 for small teams.

The honest friction point is DNS. Getting MX, SPF, DKIM, DMARC, and a reverse PTR record correctly configured is where most people slow down, and that complexity is not mailcow-specific, just a prerequisite of running your own mail server. Once DNS is sorted, the web UI handles daily administration without needing the command line, and Reddit’s self-hosted community consistently names mailcow as the first recommendation for anyone wanting to own their email.

Maintained by The Infrastructure Company GmbH in Germany, with commercial support contracts available via Servercow. A key team member departed in early 2026, but development has continued with regular security updates.