Office Online Server End of Support: December 31, 2026 (No Successor)
Office Online Server reaches end of support on December 31, 2026. Microsoft announced the retirement on October 21, 2025, and its lifecycle page lists a single retirement date under the Modern Lifecycle Policy. After that day the server receives no security updates, no bug fixes and no technical support from Microsoft. There is no extended support phase, no paid extension, and, unusually for a Microsoft server product, no next version to move to.
The dates Microsoft publishes
| Product | Released | Support ends | Policy |
|---|---|---|---|
| Office Online Server the on-premises server behind browser-based Word, Excel, PowerPoint and OneNote | May 4, 2016 | December 31, 2026 | Modern Lifecycle Policy: one retirement date, no extended support |
Sources: Microsoft's lifecycle page for Office Online Server, which states the retirement in Pacific time (the last moment of December 31, 2026), and the Office End of Support blog post Announcing the retirement for Office Online Server (October 21, 2025, updated April 2, 2026).
What Office Online Server does, and what depends on it
Office Online Server is the on-premises server that renders Word, Excel, PowerPoint and OneNote files in a browser. It shipped on May 4, 2016 as the successor to Office Web Apps Server 2013 and was never given a successor of its own. Organisations rarely install it for its own sake; it is a dependency of other Microsoft servers:
- SharePoint Server: opening and editing documents in the browser, document previews in libraries and search results, and co-authoring. SharePoint Server 2016 and 2019 both reached end of support on July 14, 2026; SharePoint Server Subscription Edition is the one still supported, and it is the one the retirement affects.
- Exchange Server: attachment previews and browser editing of attachments in Outlook on the web.
- Skype for Business Server: PowerPoint sharing in meetings.
- Power BI Report Server: viewing Excel workbooks in the report server. Microsoft states that this scenario will no longer be supported, and points to the Excel desktop application or the Power BI service instead.
What stops on the date
The server does not switch itself off, and the servers that use it keep running. What ends is everything that keeps it safe to leave on a network: security updates, bug fixes and Microsoft technical support. Microsoft's announcement puts the risk plainly: systems running it "may be vulnerable to the evolving threat landscape", and regulated organisations may be out of compliance. A server whose whole job is to open documents that arrive from outside is a poor candidate for running unpatched.
The replacements Microsoft lists
| If you use Office Online Server for | Microsoft's stated path |
|---|---|
| Browser editing and co-authoring of documents | Microsoft 365, whose Office for the web apps provide Word, Excel, PowerPoint and OneNote in the browser with real-time co-authoring |
| Document editing inside a line-of-business or custom application | SharePoint Embedded, which uses Microsoft 365's co-authoring services inside your own app |
| Documents hosted on SharePoint Server Subscription Edition or Exchange Server Subscription Edition | Desktop clients: Microsoft 365 Apps for Enterprise, or Office LTSC 2024, supported to October 9, 2029 |
| Excel workbooks in Power BI Report Server | The Excel desktop application, or migration to the Power BI service |
Notice what is not on the list: another on-premises server. Microsoft says it is "focusing its browser-based Office app investments on Office for the Web" through Microsoft 365. An organisation that stays fully on-premises after 2026 keeps document editing on the desktop and loses the browser experience.
What to do
- Find every farm that points at it. In SharePoint, the WOPI bindings show whether a farm is connected to an Office Online Server; Exchange and Skype for Business each hold the server's discovery URL in their own configuration.
- Decide per workload. Browser editing moves to Microsoft 365 or SharePoint Embedded; on-premises document stores keep desktop Office; Power BI Report Server workbooks move to Excel or the Power BI service.
- Disconnect before you decommission. Microsoft's configuration guide for SharePoint Server includes the steps to disconnect a farm from Office Online Server so that document links fall back cleanly to the desktop apps instead of failing.
- Check the neighbours. Office Online Server usually lives next to servers with their own deadlines. SharePoint Server, Exchange Server and Windows Server dates are on their product pages, and Office 2021 ends on October 13, 2026, before Office Online Server does.
Frequently Asked Questions
When is Office Online Server end of support?
Microsoft lists the retirement date of Office Online Server as December 31, 2026. After that date it receives no security updates, bug fixes or technical support. There is no extended support phase and no paid extension.
Is there a new version of Office Online Server?
No. Microsoft's retirement announcement names no on-premises successor. Its recommended path is Microsoft 365, whose Office for the web apps replace the browser editing Office Online Server provided, with SharePoint Embedded for applications that need document editing built in.
What happens to SharePoint Server and Exchange Server after Office Online Server retires?
The servers themselves are unaffected; what disappears is browser-based viewing and editing of Office documents stored on them. Microsoft states that Microsoft 365 Apps for Enterprise and Office LTSC 2024 remain supported desktop clients for documents hosted on SharePoint Server Subscription Edition and Exchange Server Subscription Edition.
Related
- Office Online Server — live status and EOL Risk Score
- SharePoint Server — every version's dates, including Subscription Edition
- SharePoint 2016 and 2019 end of support
- Exchange Server end of life
- Office 2021 end of life: October 13, 2026