Stalwart Mail & Collaboration Server

One server for your email, calendars, contacts and shared files, with spam and phishing protection built in. Every standard protocol your clients already speak (JMAP, IMAP, POP3, SMTP, CalDAV, CardDAV and WebDAV) supported natively.

Running mail used to mean stitching together half a dozen separate components (an MTA, a message store, a spam filter, a calendar server, a contacts server, a file server) each with its own configuration quirks. Stalwart collapses all of that into one platform: fewer services to deploy, one configuration to learn, one place to look when something needs attention, and a smaller attack surface.