Self-hosted alternatives to Microsoft Exchange
Want email, calendar and contacts server without handing your data to Microsoft Exchange? These 30 self-hosted apps run on your own server. Cheapest estimated hosting starts at about $5/month.
About Microsoft Exchange: Microsoft's email, calendar and contacts server.
| App | Health | Stars | License | Docker | RAM (est.) | From |
|---|---|---|---|---|---|---|
| Nextcloud | Active | 37.4k | AGPL-3.0 | – | 2 GB | $10/mo |
| docker-mailserver | Active | 19.7k | MIT | ✓ | 4 GB | $20/mo |
| Postal | Active | 16.9k | MIT | ✓ | 4 GB | $20/mo |
| Stalwart Mail Server | Active | 15.7k | AGPL-3.0 | ✓ | 4 GB | $20/mo |
| Mail-in-a-Box | Active | 15.5k | CC0-1.0 | – | 4 GB | $20/mo |
| Mailcow | Active | 13.7k | GPL-3.0 | ✓ | 8 GB | $40/mo |
| Mailu | Active | 7.6k | MIT | ✓ | 4 GB | $20/mo |
| SimpleLogin | Active | 7.1k | MIT | ✓ | 4 GB | $20/mo |
| Maddy Mail Server | Active | 6.1k | GPL-3.0 | – | 4 GB | $20/mo |
| Mox | Active | 5.9k | MIT | – | 4 GB | $20/mo |
| Radicale | Active | 5.2k | GPL-3.0 | – | 1 GB | $5/mo |
| AnonAddy | Active | 4.9k | MIT | ✓ | 4 GB | $20/mo |
| Modoboa | Active | 3.5k | ISC | – | 4 GB | $20/mo |
| Baïkal | Active | 3.4k | GPL-3.0 | – | 1 GB | $5/mo |
| SOGo | Active | 2.2k | LGPL-2.1 | – | 4 GB | $20/mo |
| wildduck | Active | 2.1k | EUPL-1.2 | ✓ | 4 GB | $20/mo |
| iRedMail | Active | 1.9k | GPL-3.0 | – | 4 GB | $20/mo |
| SabreDAV | Active | 1.7k | MIT | – | 1 GB | $5/mo |
| Forward Email | Active | 1.7k | BUSL-1.1, MPL-2.0 | ✓ | 4 GB | $20/mo |
| Keeper.sh | Active | 1.4k | AGPL-3.0 | ✓ | 1 GB | $5/mo |
| DavMail | Active | 773 | GPL-2.0 | – | 2 GB | $10/mo |
| Openmeetings | Active | 688 | Apache-2.0 | ✓ | 4 GB | $20/mo |
| Manage My Damn Life | Active | 644 | GPL-3.0 | ✓ | 1 GB | $5/mo |
| Xandikos | Active | 612 | GPL-3.0 | – | 1 GB | $5/mo |
| Simple NixOS Mailserver | Active | 321 | GPL-3.0 | – | 4 GB | $20/mo |
| egroupware | Active | 302 | GPL-2.0 | – | 4 GB | $20/mo |
| Group Office | Active | 285 | AGPL-3.0 | – | 4 GB | $20/mo |
| dayGLANCE | Active | 182 | MIT | ✓ | 1 GB | $5/mo |
| DAViCal | Maintained | 112 | GPL-2.0 | – | 1 GB | $5/mo |
| Tine | Active | 22 | AGPL-3.0 | ✓ | 4 GB | $20/mo |
The options in detail
1. Nextcloud
Access and share your files, calendars, contacts, mail and more from any device, on your terms.
Active Last commit 2026-11-05. Latest release v35.0.2 (2026-10-15). Needs roughly 2 GB RAM. How to run it →
2. 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.
Active Last commit 2026-11-02. 2 releases in the past year. Latest release v16.0.1 (2026-09-04). Needs roughly 4 GB RAM. How to run it →
3. Postal
Complete and fully featured mail server for use by websites & web servers.
Active Last commit 2026-10-01. Latest release 3.3.7 (2026-06-03). Needs roughly 4 GB RAM. How to run it →
4. Stalwart Mail Server
All-in-one mail server with JMAP, IMAP4, and SMTP support and a wide range of modern features.
Active Last commit 2026-11-04. Latest release v1.0.3 (2026-11-04). Needs roughly 4 GB RAM. How to run it →
5. Mail-in-a-Box
Turns any Ubuntu server into a fully functional mail server with one command.
Active Last commit 2026-10-22. Latest release v77 (2026-09-26). Needs roughly 4 GB RAM. How to run it →
6. Mailcow
Mail server suite based on Dovecot, Postfix and other software, that provides a modern Web UI for administration.
Active Last commit 2026-10-21. Latest release 2026-10 (2026-10-21). Needs roughly 8 GB RAM. How to run it →
7. Mailu
Simple yet full-featured mail server as a set of Docker images.
Active Last commit 2026-11-04. Latest release 2024.06.67 (2026-10-23). Needs roughly 4 GB RAM. How to run it →
8. SimpleLogin
Email alias solution to protect your email address. Comes with browser extensions and mobile apps.
Active Last commit 2026-11-04. Latest release v4.83.4 (2026-11-04). Needs roughly 4 GB RAM. How to run it →
9. Maddy Mail Server
All-in-one mail server that implements SMTP (both MTA and MX) and IMAP. Replaces Postfix, Dovecot, OpenDKIM, OpenSPF, OpenDMARC with single daemon.
Active Last commit 2026-11-04. 8 releases in the past year. Latest release v0.9.6 (2026-10-03). Needs roughly 4 GB RAM. How to run it →
10. Mox
Complete e-mail solution with IMAP4, SMTP, SPF, DKIM, DMARC, MTA-STS, DANE and DNSSEC, reputation-based and content-based junk filtering, Internationalization (IDNA), automatic TLS with ACME and Let's Encrypt, account autoconfiguration, and webmail.
Active Last commit 2026-10-27. Latest release v0.0.17 (2026-08-19). Needs roughly 4 GB RAM. How to run it →
11. Radicale
Simple calendar and contact server with extremely low administrative overhead.
Active Last commit 2026-11-04. Latest release v3.9.0 (2026-10-25). Needs roughly 1 GB RAM. How to run it →
12. AnonAddy
Email forwarding service for creating aliases.
Active Last commit 2026-10-29. 10+ releases in the past year. Latest release v1.7.4 (2026-10-29). Needs roughly 4 GB RAM. How to run it →
13. Modoboa
Mail hosting and management platform including a modern and simplified web user interface.
Active Last commit 2026-11-04. Latest release 2.12.0 (2026-10-26). Needs roughly 4 GB RAM. How to run it →
14. Baïkal
Lightweight CalDAV and CardDAV server based on sabre/dav.
Active Last commit 2026-11-03. Latest release 0.13.0 (2026-10-19). Needs roughly 1 GB RAM. How to run it →
15. SOGo
SOGo offers multiple ways to access the calendaring and messaging data. CalDAV, CardDAV, GroupDAV, as well as ActiveSync, including native Outlook compatibility and Web interface.
Active Last commit 2026-11-03. 9 releases in the past year. Latest release SOGo-5.12.13 (2026-11-04). Needs roughly 4 GB RAM. How to run it →
16. wildduck
Scalable no-SPOF IMAP/POP3 mail server.
Active Last commit 2026-11-03. Latest release v1.55.3 (2026-11-02). Needs roughly 4 GB RAM. How to run it →
17. iRedMail
Full-featured mail server solution based on Postfix and Dovecot.
Active Last commit 2026-10-28. Needs roughly 4 GB RAM. How to run it →
18. SabreDAV
CardDAV, CalDAV, and WebDAV framework and server.
Active Last commit 2026-11-01. Latest release 4.7.1 (2026-07-07). Needs roughly 1 GB RAM. How to run it →
19. Forward Email
Privacy-focused encrypted email for everyone. All-in-one (alternative to Gmail, Mailchimp, Sendgrid).
Active Last commit 2026-11-05. 10+ releases in the past year. Latest release v2.19.0 (2026-11-04). Needs roughly 4 GB RAM. How to run it →
20. Keeper.sh
Calendar syncing tool that pulls and pushes events between calendar sources and destinations via iCal/ICS or OAuth, with support for anonymized busy/free events.
Active Last commit 2026-11-04. Latest release v2.28.11 (2026-11-03). Needs roughly 1 GB RAM. How to run it →
21. DavMail
POP/IMAP/SMTP/Caldav/Carddav/LDAP exchange gateway allowing users to use any mail/calendar client with an Exchange server, even from the internet or behind a firewall through Outlook Web Access.
Active Last commit 2026-11-02. Needs roughly 2 GB RAM. How to run it →
22. Openmeetings
Video conferencing, instant messaging, whiteboard, collaborative document editing and other groupware tools using API functions of the Red5 Streaming Server for Remoting and Streaming.
Active Last commit 2026-11-03. 2 releases in the past year. Latest release 9.1.0 (2026-07-14). Needs roughly 4 GB RAM. How to run it →
23. Manage My Damn Life
Manage my Damn Life (MMDL) is a front end for managing your CalDAV tasks and calendars.
Active Last commit 2026-09-13. Latest release v0.10.0 (2026-09-13). Needs roughly 1 GB RAM. How to run it →
24. Xandikos
CardDAV and CalDAV server with minimal administrative overhead, backed by a Git repository.
Active Last commit 2026-11-02. Latest release v0.4.10 (2026-10-17). Needs roughly 1 GB RAM. How to run it →
25. Simple NixOS Mailserver
Complete mailserver solution leveraging the Nix Ecosystem.
Active Last commit 2026-10-21. Latest release v2.3.0 (2019-12-16). Needs roughly 4 GB RAM. How to run it →
26. egroupware
Software suite including calendars, address books, notepad, project management tools, client relationship management tools (CRM), knowledge management tools, a wiki and a CMS.
Active Last commit 2026-11-04. 10+ releases in the past year. Latest release 26.10.20261030 (2026-10-30). Needs roughly 4 GB RAM. How to run it →
27. Group Office
Enterprise CRM and groupware tool. Share projects, calendars, files and e-mail online with co-workers and clients.
Active Last commit 2026-11-04. Latest release v25.0.115 (2026-11-03). Needs roughly 4 GB RAM. How to run it →
28. dayGLANCE
Day planner with drag-and-drop time blocking, inbox, recurring tasks, habits, routines, goals, projects and Pomodoro focus mode, plus iCal and CalDAV calendar sync. Data stays in the browser, with optional WebDAV or GLANCEvault sync.
Active Last commit 2026-11-05. Latest release v5.11.0 (2026-11-01). Needs roughly 1 GB RAM. How to run it →
29. DAViCal
Server for calendar sharing (CalDAV) that uses a PostgreSQL database as a data store.
Maintained Last commit 2026-05-27. Needs roughly 1 GB RAM incl. postgres. How to run it →
30. Tine
Software for digital collaboration in companies and organizations. From powerful groupware functionalities to clever add-ons, tine combines everything to make daily team collaboration easier.
Active Last commit 2026-11-04. Latest release weekly-2026.44.1 (2026-10-31). Needs roughly 4 GB RAM. How to run it →
Why self-host instead of Microsoft Exchange?
- Own your data — it lives on a server you control, with backups you decide on.
- Predictable cost — a small VPS often replaces per-seat pricing for a whole team or family.
- No lock-in — open-source licenses let you keep running the software even if a vendor disappears.
The trade-off: you are responsible for updates, backups and security. Pick an app marked Active (a commit in the last 90 days) and with Docker support for the easiest ride.
Browse related categories
Other alternatives guides
Microsoft Exchange is a trademark of its owner; this site is not affiliated with it. Listings come from the community-maintained awesome-selfhosted list.