6 self-hosted options
Open-source alternatives to Microsoft 365
The best open-source alternatives to Microsoft 365 are Nextcloud, ONLYOFFICE and egroupware.
About Microsoft 365: Microsoft's subscription suite of Office apps, Exchange mail and Teams chat.
Every option below is free to self-host and ranked by GitHub stars, so you can move off Microsoft 365 without giving up the features you rely on.
Top picks
- Rank 1:
Nextcloud
nextcloud/server
Access and share your files, calendars, contacts, mail and more from any device, on your terms.
FeaturedFile Sync & StoragePHP - Rank 2:
ONLYOFFICE
ONLYOFFICE/DocumentServer
Office suite that enables you to manage documents, projects, team and customer relations in one place.
Office SuitesShellDocker - Rank 3:
egroupware
EGroupware/egroupware
Software suite including calendars, address books, notepad, project management tools, client relationship management tools (CRM), knowledge management tools, a wiki and a CMS.
Groupware & CalendarsPHP
Why switch
Why teams move off Microsoft 365
Self-hosting is not only about saving money. These are the reasons people make the switch.
Own your data
Your data lives on a server you control, not on Microsoft 365's infrastructure. No surprise policy changes and no lock-in.
No per-seat pricing
Open-source alternatives to Microsoft 365 are free to run for as many users as your server can handle. A small VPS often costs less than a single subscription.
Customize and extend
Read the code, add plugins, connect it to your own tools and automate it through open APIs. When you need a feature, you can build it or fund it.
Full ranking
All 6 Microsoft 365 alternatives
Ranked by GitHub stars. Open any app for live stats, license details and a deploy option.
- 1
NextcloudFeatured
Access and share your files, calendars, contacts, mail and more from any device, on your terms.
File Sync & Storage - 2
ONLYOFFICE
Office suite that enables you to manage documents, projects, team and customer relations in one place.
Office SuitesDocker - 3
egroupware
Software suite including calendars, address books, notepad, project management tools, client relationship management tools (CRM), knowledge management tools, a wiki and a CMS.
Groupware & Calendars - 4
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.
Groupware & Calendars - 5
CryptPad
Collaboration suite built to enable collaboration, synchronizing changes to documents in real time.
Office SuitesDocker - 6
Mailcow
Mail server suite based on Dovecot, Postfix and other open source software, that provides a modern Web UI for administration.
Email ServersDocker
What is the best open-source alternative to Microsoft 365?
Nextcloud is the most popular open-source alternative to Microsoft 365, with 37,003 GitHub stars. ONLYOFFICE and egroupware are also strong choices. Compare features, license and recent activity to find the best fit for your team.
Is there a free alternative to Microsoft 365?
Yes. All 6 apps on this page are open source and free to self-host, so you can run a Microsoft 365 replacement without per-user fees. You only pay for the server, and a small VPS is usually enough for personal use or a small team.
Can I self-host an alternative to Microsoft 365?
Yes. ONLYOFFICE, CryptPad and Mailcow ship a Docker image, so you can run them on a home server or VPS with Docker Compose in a few minutes. Your data then stays on hardware you control.
How do I migrate from Microsoft 365?
Start by exporting your data from Microsoft 365, then check the import options of the app you pick, since many projects ship importers for popular formats. Run both side by side for a week before you switch so nothing is lost.