Office Online Server End of Life (EOL) Dates & Support Timeline
Complete end-of-life dates, support windows, and security status for all Office Online Server versions. Data sourced from endoflife.date and official vendor documentation. Updated at every deploy.
Running an EOL version? Get matched with support options — free ↓| Version | Latest Release | Release Date | EOL Date | Days | Status |
|---|---|---|---|---|---|
| Office Online Server | — | May 4, 2016 | Dec 31, 2026 | 118 days remaining | Warning |
Live EOL badge for your README — updates automatically at every build.
[](https://endoflife.ai/office-online-server)
Office Online Server lifecycle status — the real story
Office Online Server is the on-premises server that renders browser-based Word, Excel, PowerPoint and OneNote for SharePoint Server, Exchange Server and Skype for Business deployments — the successor to Office Web Apps Server, released May 4, 2016 and serviced since then as a single product line under Microsoft's Modern Lifecycle Policy rather than as numbered versions. That policy is why it appears on none of Microsoft's year-by-year end-of-support roll-ups: its only public date lives on its own lifecycle page.
Microsoft announced the retirement on October 21, 2025 (Office End Of Support blog): support for Office Online Server ends December 31, 2026 — the lifecycle page states the retirement as 1/1/2027 6:59:59 AM Pacific, which is the same instant. After that date it receives no security updates, bug fixes or technical support. Microsoft's stated paths are Microsoft 365 (Office for the web) and SharePoint Embedded for in-app co-authoring; for SharePoint Server Subscription Edition and Exchange Server Subscription Edition customers, Microsoft 365 Apps for enterprise and Office LTSC 2024 remain the supported desktop clients. Excel workbooks hosted in Power BI Report Server through Office Online Server lose that function entirely.
The practical trap is that Office Online Server is a dependency, not a headline product: it is installed beside a SharePoint or Exchange farm and forgotten. The retirement lands eleven weeks after the October 13, 2026 Office 2021 / Windows Server 2012 ESU cluster and inside the same budget cycle as the SharePoint Server 2016/2019 end of support that already passed on July 14, 2026.
What does Office Online Server end of life mean for your organization?
When a version of Office Online Server reaches end of life, the maintainers stop issuing security patches. Vulnerabilities discovered after this date are publicly disclosed on the National Vulnerability Database, exploit code appears on GitHub, and your systems remain permanently exposed.
The CVE blind spot: Most vulnerability scanners check for known CVEs but do not flag the accumulation of unpatched vulnerabilities in EOL software. With a zero-day, nobody knows about the vulnerability. With EOL software, the vulnerability is public — listed, rated, and often weaponized — but no patch will ever exist. This is the most dangerous gap in enterprise security posture.
Organizations running EOL Office Online Server should treat it as a vulnerability class in their risk register, apply compensating controls (network segmentation, enhanced monitoring, access restriction), and prioritize migration to a supported version.
Your options when Office Online Server reaches end of life
There are four realistic paths. Which one is right depends far more on how long the system needs to keep running than on the version you are on today.
| Option | Best when | Watch out for |
|---|---|---|
| Move to a supported version | The system will outlive the current version's support window and you can schedule the work | Budget for compatibility testing, not just the upgrade itself — that is where the real cost sits |
| Replace the component | The project is unmaintained, or a better-supported alternative exists | The replacement has its own lifecycle and its own end-of-life date — you are changing vendors, not escaping the problem |
| Buy extended support | Migration is genuinely underway but cannot finish before the deadline, or the workload is frozen by certification or a third-party application | A bridge, not a destination — every year purchased is a year the migration still has to happen |
| Document accepted risk | The system is isolated, short-lived, or scheduled for retirement | Only defensible with real compensating controls and a written decision — auditors treat undocumented end-of-life software as a finding |
How to choose, in one question: how many more years does this system need to run? Under a year, extended support (where it exists) is usually cheaper than an emergency migration. One to three years, migrate — support purchased repeatedly costs more than doing the project once, and the project only gets harder as the version ages. Indefinitely, migrate now and plan the next migration before it surprises you.
Worth saying plainly, because vendors selling extended support rarely will: extended support is often the more expensive choice over a multi-year horizon. It is the right answer when a deadline is genuinely unreachable, not as a default. Compare the annual fee against the one-time cost of migrating before committing to either.
Formalizing decisions like this across your estate? Our free EOL policy template is a ready-to-adopt policy with risk tiers, remediation SLAs, and audit mapping — no signup, free to use and share.
Extended Support Options
If you cannot migrate immediately, extended support vendors provide continued security patches for EOL Office Online Server versions. This is a bridge, not a permanent solution — plan your migration in parallel.
When Office Online Server versions reach end of life, security patches stop — the CVEs keep coming. Extended support past the official date exists for many products in this position — whether it exists for Office Online Server is exactly what we check. Tell us where to reach you and we'll reply with matched options and pricing guidance — or an honest "no vendor covers this."