Office 2021 End of Support (Oct 13, 2026): What to Do
Short answer: Microsoft ends support for Office 2021 on October 13, 2026, with no paid extension. Your Word, Excel, PowerPoint and Outlook keep opening and working, but they stop receiving security updates and bug fixes, and connecting Outlook 2021 to Microsoft 365 services is no longer a supported setup. To stay patched, move to Office 2024 (supported until October 9, 2029) or a Microsoft 365 subscription.
Microsoft’s support for Office 2021 ends on October 13, 2026. That date covers Office Home & Student 2021, Home & Business 2021, Professional Plus 2021, Office LTSC 2021 and Office 2021 for Mac. There is no extended phase and no paid security-update program, so the date is final.
The short version: your Office 2021 apps don’t switch off. They keep opening, editing and saving files exactly as before. What ends is maintenance — and that matters more than it sounds, because Office documents are one of the most common ways malicious code gets onto a PC.
What Stops on October 13, 2026
According to Microsoft’s end-of-support notice for Office 2021, after that date:
- No more security updates. Vulnerabilities found in Word, Excel, PowerPoint or Outlook 2021 after October 13 won’t be patched.
- No more bug fixes or software updates through Microsoft Update.
- No phone or chat technical support from Microsoft for Office 2021.
- Online help content for Office 2021 is no longer maintained.
Office 2021 follows Microsoft’s Modern Lifecycle Policy: five years of support and then nothing. Older versions such as Office 2016 and 2019 had an extra “extended support” phase; Office 2021 does not.
What Keeps Working
- Opening, editing and saving
.docx,.xlsxand.pptxfiles. - Your existing license and activation. You don’t need to reactivate or re-buy anything to keep using the apps.
- Files you share with people on newer Office versions. The file formats haven’t changed.
What you lose is protection, not functionality. An unpatched Office install is fine on an offline PC that never opens files from email or the web. On a normal home or work PC that does both, it becomes a growing risk with every month that passes.
The Outlook and Microsoft 365 Catch
This is the part most people miss. Microsoft only supports connecting Office versions that are themselves in support to Microsoft 365 services such as Exchange Online, OneDrive and SharePoint. Its connectivity policy lists Office 2021 as supported for these connections only until October 13, 2026.
In practice:
- Outlook 2021 won’t lose your mailbox overnight. It will usually keep syncing.
- New service features may not work with it.
- If a connection or performance problem appears later, Microsoft won’t fix it for Office 2021.
If your business email runs through Microsoft 365, plan the move to a supported Outlook rather than waiting for something to break.
How to Check Which Office Version You Have
Open Word or Excel, then go to File → Account and look under Product Information. You’ll see the product name, for example “Office Home & Business 2021” or “Microsoft 365”. Click About Word (or Excel) for the exact version and build number.
If it says Microsoft 365, you’re on the subscription and this deadline doesn’t affect you. If it says 2021, read on. If it says 2019 or 2016, you are already past end of support — those versions stopped getting security updates on October 14, 2025.
Your Options Compared
| Option | Cost model | Security updates until | Good fit for |
|---|---|---|---|
| Keep Office 2021 | Nothing extra | Ended October 13, 2026 | Offline PCs that never open outside files |
| Office 2024 (one-time license) | One-time purchase | October 9, 2029 | Anyone who wants desktop Office without a subscription |
| Microsoft 365 | Monthly or yearly subscription | Always current while subscribed | Several devices, 1 TB OneDrive storage, always-new features |
| Office for the web | Free with a Microsoft account | Always current | Light editing in a browser |
Office 2024 also follows the Modern Lifecycle Policy, with support ending on October 9, 2029 according to Microsoft’s lifecycle page. That’s three more years of security updates from a single purchase.
Moving from Office 2021 to Office 2024
The upgrade itself is straightforward:
- Note what you use. If you need Outlook or Access, pick an edition that includes them. Office Home 2024 covers Word, Excel, PowerPoint and OneNote; Professional Plus adds Outlook and Access.
- Back up your Outlook data if you use a local
.pstfile (File → Open & Export → Import/Export → Export to a file). - Uninstall Office 2021 from Settings → Apps → Installed apps, so the two versions don’t conflict.
- Install and activate Office 2024 with your new key.
- Reopen Outlook and add your account again, or point it at your backed-up data file.
Your documents don’t need converting. Office 2024 opens Office 2021 files as they are.
Where RebootDoctor Fits
We sell Microsoft Office 2024 keys — Office Home ($5.50) or Professional Plus ($6.99) — as a one-time purchase delivered by email. The product page has a side-by-side table of every Office version we carry, with the Microsoft support dates for each, so you can see what you’re buying before you pay.
If you’re unsure which edition you need, or you get stuck on activation, message us on WhatsApp and we’ll help before or after you buy.
Frequently Asked Questions
Will Office 2021 stop working after October 13, 2026?
No. Office 2021 keeps opening, editing and saving files after the end-of-support date. What stops is maintenance: Microsoft no longer ships security updates, bug fixes or technical support for it, and its online help content is retired.
Is there an Extended Security Updates (ESU) program for Office 2021?
No. Office 2021 follows Microsoft's Modern Lifecycle Policy, which has no extended support phase, and Microsoft has not announced a paid security-update program for it. October 13, 2026 is the last day it is supported.
Can I still use Outlook 2021 with my Microsoft 365 or Outlook.com mailbox?
It will usually keep connecting, but after October 13, 2026 Microsoft no longer supports Office 2021 for connecting to Microsoft 365 services. New service features may not work with it, and performance or reliability problems will not be fixed. If email is critical, use a supported Outlook version.
Does the end date also apply to Office LTSC 2021 and Office 2021 for Mac?
Yes. Office Home & Student 2021, Office Home & Business 2021, Office Professional Plus 2021, Office LTSC 2021 and Office 2021 for Mac all reach end of support on October 13, 2026.
What is the cheapest way to stay on supported Office?
A one-time Office 2024 license is supported until October 9, 2029 with no subscription. Microsoft 365 costs a yearly fee but always stays current. If you only need basic documents, the free Office for the web in a browser is also supported.