Free Microsoft Exchange Server Alternatives for Linux

Microsoft Exchange Server is not available for Linux but there are plenty of alternatives that runs on Linux with similar functionality. The best free Linux alternative is Kolab Community, which is also Open Source. If that doesn't suit you, our users have ranked more than 25 alternatives to Microsoft Exchange Server and 15 are free and available for Linux so hopefully you can find a suitable replacement. Other interesting free Linux alternatives to Microsoft Exchange Server are mailcow: dockerized, Zimbra Collaboration Suite, SOGo and OX App Suite.

Microsoft Exchange Server alternatives are mainly Mail Servers but may also be WebMail Providers or Calendar Apps. Filter by these if you want a narrower list of alternatives or looking for a specific functionality of Microsoft Exchange Server.

Microsoft Exchange Server alternatives page was last updated

Microsoft Exchange Server

Paid • Proprietary
Mail Server

Microsoft Exchange Server is a messaging and collaborative software product developed by Microsoft. It is part of the...

More about Microsoft Exchange Server

Kolab Community
Is this is a good alternative?
Yes
No
Freemium • Open Source
Linux
Online
Self-Hosted
42 Kolab Community alternatives
Kolab is entirely Free and Open Source Software (a.k.a. FOSS), and uses Open Standards. We’ll get to why this is important to us, and hope that it is important to you thereafter.
- - Kolab Community is the most popular Self-Hosted alternative to Microsoft Exchange Server.
- - Kolab Community is the most popular Open Source & free alternative to Microsoft Exchange Server.
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Kolab Community Features
1. Real time collaborationMultiple users can work together in Kolab Community simultaneously.
CalDAV Support
WebDAV Support
IMAP Support
CardDAV Support
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Opinions about Kolab Community as a Alternative to Microsoft Exchange Server
Most users think Kolab Community is a great Microsoft Exchange Server alternative.
mailcow: dockerized
Is this is a good alternative?
Yes
No
Free • Open Source
Mail Server
WebMail Provider
Linux
Self-Hosted
18 mailcow: dockerized alternatives
mailcow is a mail server suite based on Dovecot, Postfix, SOGo, Rspamd and other open source software, that provides a modern Web UI for administration.
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mailcow: dockerized Features
1. Dark Modemailcow: dockerized supports dark mode for comfortable usage in low light conditions.
2. Ad-freemailcow: dockerized doesn't contain any form of external advertising.
3. Two-factor Authenticationmailcow: dockerized supports two-factor authentication (2FA).
4. Mail Filteringmailcow: dockerized classifies email messages according to specified criteria, allowing you to automatically recognize fraudulent or spam messages.
5. Email Organizermailcow: dockerized allows you to take control of your inbox by filtering and control tools.
6. Spam Filtermailcow: dockerized can detect unsolicited, unwanted and virus-infected emails, calls, files, etc.
7. Support for Aliasesmailcow: dockerized supports aliases, so you can receive email without exposing your main email address
Self hosted mail
Support for Docker
ActiveSync
Modular System
Dockerized
Zimbra Collaboration Suite
Is this is a good alternative?
Yes
No
Freemium • Open Source
Mail Server
Calendar App
Team Collaboration Tool
Linux
Online
Self-Hosted
41 Zimbra Collaboration Suite alternatives
Zimbra Collaboration is an open, secure collaboration tool for email, calendaring, tasks and more. With the most innovative web application available today, Zimbra boosts the productivity of users on any desktop and dramatically reduces TCO compared to legacy platform vendors.
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Zimbra Collaboration Suite Features
1. Real time collaborationMultiple users can work together in Zimbra Collaboration Suite simultaneously.
ActiveSync
Active Directory integration
Opinions about Zimbra Collaboration Suite as a Alternative to Microsoft Exchange Server
Most users think Zimbra Collaboration Suite is a great Microsoft Exchange Server alternative.
SOGo
Is this is a good alternative?
Yes
No
Freemium • Open Source
WebMail Provider
Linux
Online
Thunderbird
Cloudron
65 SOGo alternatives
SOGo is groupware server with a focus on scalability and open standards.

SOGo provides a rich AJAX-based Web interface and supports multiple native clients through the use of standard protocols such as CalDAV, CardDAV and GroupDAV.Share your calendars, address books and mails in.
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SOGo Features
Support for Multiple Users
Scheduling
CalDAV Support
CardDAV Support
OX App Suite
Is this is a good alternative?
Yes
No
Free • Open Source
Mail Server
WebMail Provider
Calendar App
Linux
Online
Self-Hosted
Software as a Service (SaaS)
20 OX App Suite alternatives
The OX App Suite by Open-Xchange is web-based platform offering a suite of apps like an email client, calendar, contacts magement, cloud storage with synchronization and productivity apps for word processing, spreadsheets and presentations.
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OX App Suite Features
1. Real time collaborationMultiple users can work together in OX App Suite simultaneously.
2. Cloud SyncSync your data (notes, documents, bookmarks, etc.) across your different devices and to the cloud.
3. Calendar IntegrationOX App Suite lets you sync your tasks and events with your calendar application.
Personal Information Manager (PIM)
Group Mail
German
WebDAV Support
WebDAV Sync
Opinions about OX App Suite as a Alternative to Microsoft Exchange Server
Most users think OX App Suite is a great Microsoft Exchange Server alternative.
OpenChange
Is this is a good alternative?
Yes
No
Free • Open Source
Mail Server
Linux
30 OpenChange alternatives
OpenChange aims to provide a portable Open Source implementation of Microsoft Exchange Server and Exchange protocols.
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OpenChange Features
Exchange
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iRedMail
Is this is a good alternative?
Yes
No
Freemium • Open Source
Mail Server
Linux
BSD
Self-Hosted
69 iRedMail alternatives
A fully fledged, free email server solution, an open source project (GPL v2).

Use official binary packages from Linux/BSD distributions, with both i386 and x86_64 support.

Easy, fast deployment in LESS THAN 1 MINUTE. View YouTube Video to check how easy it is.

Works on both no.
iRedMail has no features, suggest some!
grommunio
Is this is a good alternative?
Yes
No
Freemium • Open Source
Calendar App
Web Conferencing Tool
Mac
Windows
Linux
Online
Android
iPhone
iPad
Self-Hosted
12 grommunio alternatives
grommunio (formerly known as grammm) efficiently combines all requirements of modern, digital communication and collaboration.
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grommunio Features
1. Real time collaborationMultiple users can work together in grommunio simultaneously.
Contacts
Self hosted mail
RPC
Support for Docker
CardDAV Support
IMAP Support
CalDAV Support
SMTP Support
POP3 Support
Comments about grommunio as a Alternative to Microsoft Exchange Server
Almost everyone thinks grommunio is a great Microsoft Exchange Server alternative.
norbertlambing
As the first open source solution to offer a full-featured OutlookAnywhere (RPC over HTTP) and MAPI/HTTP implementation, grammm is the alternative to proprietary backends for native interoperability with Microsoft Outlook
Positive comment•
1
Poste.io
Is this is a good alternative?
Yes
No
Free Personal • Proprietary
Mail Server
Linux
17 Poste.io alternatives
Full featured solution for your Email server. Native implementation of last anti-SPAM metods, webmail and easy administration included.
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Poste.io Features
Support for Docker
Citadel
Is this is a good alternative?
Yes
No
Free • Open Source
WebMail Provider
Calendar App
Linux
Online
17 Citadel alternatives
Is a collaboration suite (messaging and groupware). It is designed to run on open source operating systems such as Linux or BSD. In order to modernize the Citadel platform for the Internet, the Citadel/UX developers added functionality such as shared calendars, instant...
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Citadel Features
1. Real time collaborationMultiple users can work together in Citadel simultaneously.
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