OpenSourceProjects

Open Source Microsoft Exchange Alternatives

Discover 17 open source alternatives to Microsoft Exchange. All free, community-driven, and actively maintained.

What is Microsoft Exchange?

Microsoft Exchange is an enterprise email, calendar, and collaboration server platform.

Visit Microsoft Exchange

docker-mailserver

docker-mailserver

Production-ready fullstack but simple mail server (SMTP, IMAP, LDAP, Antispam, Antivirus, etc.) running inside a container.

mailinabox

mailinabox

Mail-in-a-Box helps individuals take back control of their email by defining a one-click, easy-to-deploy SMTP+everything else server: a mail server in a box.

mailcow-dockerized

mailcow-dockerized

mailcow: dockerized - 🐮 + 🐋 = 💕

stalwart

stalwart

All-in-one Mail & Collaboration server. Secure, scalable and fluent in every protocol (IMAP, JMAP, SMTP, CalDAV, CardDAV, WebDAV).

Mailu

Mailu

Insular email distribution - mail server as Docker images

roundcubemail

roundcubemail

The Roundcube Webmail suite

ejabberd

ejabberd

Robust, Ubiquitous and Massively Scalable Messaging Platform (XMPP, MQTT, SIP Server)

maddy

maddy

✉️ Composable all-in-one mail server.

mox

mox

modern full-featured open source secure mail server for low-maintenance self-hosted email

Haraka

Haraka

A fast, highly extensible, and event driven SMTP server

Radicale

Radicale

A simple CalDAV (calendar) and CardDAV (contact) server.

modoboa

modoboa

Mail hosting made simple

Baikal

Baikal

Baïkal is a Calendar+Contacts server

Openfire

Openfire

An XMPP server licensed under the Open Source Apache License.

sogo

sogo

SOGo is a very fast and scalable modern collaboration suite (groupware). It offers calendaring, address book management, and a full-featured Webmail client along with resource sharing and permission handling. It also makes use of documented standards (IMAP, CalDAV, CardDAV, etc.) and thereby provides native connectivity (without plugins) to many clients such as Microsoft Outlook, Apple iCal, the iPhone, Mozilla Lightning, and a plethora of mobile devices.

wildduck

wildduck

Opinionated email server

core

core

Dovecot mail server