Microsoft ends support for Office 2021 and Office LTSC 2021 on 13 October 2026. Your apps will still open and work, but they receive no further security updates, bug fixes or technical support. To stay protected, move to Office 2024 / Office LTSC 2024 (supported until October 2029) or to a Microsoft 365 subscription.
Written by the Softkeyworld technical team · Updated October 2026
Key takeaways
- The final security update for Office 2021 is the October 2026 Patch Tuesday release. There is no Extended Security Updates programme for it.
- Nothing is switched off: documents open, activation remains valid, and files stay fully compatible.
- The real risk is unpatched vulnerabilities in Word, Excel and Outlook, which are the apps attackers target most through malicious attachments.
- Project 2021 and Visio 2021 (including the LTSC versions) reach end of support on the same date.
- Your realistic choices are a one-time Office 2024 licence or a Microsoft 365 subscription. Both are valid, and the right one depends on how you work.
When exactly does Office 2021 support end?
The official date is Tuesday 13 October 2026. Microsoft's lifecycle database lists the cut-off as 14 October 2026 at 06:59 Pacific Time, so you may see both dates quoted. They describe the same moment: the October 2026 Patch Tuesday is the last time Office 2021 receives anything from Windows Update or the Office Click-to-Run update channel. Microsoft confirms this in its Office LTSC 2021 end of support announcement.
The consumer and small-business editions sold at retail (Home & Student 2021, Home & Business 2021 and Professional 2021) fall under the Modern Lifecycle Policy. The volume-licensed editions (Office LTSC Professional Plus 2021 and Office LTSC Standard 2021) fall under the Fixed Lifecycle Policy. These policies normally behave quite differently, but here the outcome is the same: both reach the end of the road on the same day, and neither gets an extended support phase.
Which products are affected?
| Product | Lifecycle policy | Support ends |
|---|---|---|
| Office Home & Student 2021 (PC/Mac) | Modern | 13 October 2026 |
| Office Home & Business 2021 (PC/Mac) | Modern | 13 October 2026 |
| Office Professional 2021 | Modern | 13 October 2026 |
| Office LTSC Professional Plus / Standard 2021 | Fixed | 13 October 2026 |
| Project 2021 / Project LTSC 2021 | Fixed / Modern | 13 October 2026 |
| Visio 2021 / Visio LTSC 2021 | Fixed / Modern | 13 October 2026 |
| Microsoft Publisher (all versions) | Retired product | October 2026 |
Publisher deserves its own mention. Microsoft is retiring the app altogether in October 2026 and it is not included in any Office 2024 edition. If you depend on .pub files, export them to PDF or Word now, while you still have a supported copy of Publisher to do it with.
What stops on 13 October 2026
Microsoft's end of support page for Office 2021 lists what ends:
- Security updates. Newly discovered vulnerabilities in Word, Excel, PowerPoint, Outlook, Access and the shared Office components will not be patched for 2021.
- Bug fixes and non-security updates. If a Windows 11 feature update or a printer driver breaks something in Office 2021, no fix will come.
- Technical support. Microsoft's phone and chat support will no longer troubleshoot Office 2021 problems.
- Supported Microsoft 365 connectivity. Microsoft's connectivity policy supports Office LTSC 2021 against Exchange Online, SharePoint Online and OneDrive only until 13 October 2026. After that, connections are not blocked, but they are not supported either. Microsoft warns that older versions may hit "unexpected performance or reliability issues" over time.
Microsoft has not announced an Extended Security Updates (ESU) programme for Office 2021 like the one it offered for Windows 10. You should plan as if no paid extension will appear.
What keeps working
This is the question that comes up most in our support inbox, so here is a plain answer: Office 2021 does not stop working on 14 October. There is no kill switch.
- Word, Excel, PowerPoint and the rest will launch and edit files exactly as they do today.
- Your licence stays activated. File → Account → Product Information will still show "Product Activated".
- The
.docx,.xlsxand.pptxformats are unchanged, so you can still swap files with colleagues on Office 2024 or Microsoft 365. - You can usually still reinstall from your Microsoft account or from the original installer. Over time, though, Microsoft may stop offering the download for retired versions.
One practical caveat: a fresh activation of an unsupported product is never guaranteed long term. If you are rebuilding a PC next year, do the reinstall and activation sooner rather than later, and keep your product key somewhere safe.
The real risks of staying on Office 2021
1. Unpatched document exploits
Office apps parse complex, untrusted files that arrive by email every day. Historically, many serious Office vulnerabilities have been "open a file and you are compromised" bugs in Word, Excel or Outlook's preview handling. Once support ends, every new flaw found in code that Office 2021 shares with newer versions stays permanently open on your machine. Attackers know this and pay attention to unpatched installed bases.
2. Compliance and insurance
UK schemes such as Cyber Essentials require software to be licensed and supported, with high-risk security updates applied within 14 days. An unsupported Office suite is a straightforward fail. Cyber-insurance questionnaires and client security reviews increasingly ask the same question.
3. Slow compatibility drift
Problems will not appear on day one. As Windows 11 feature updates and Microsoft 365 services move on, though, small issues build up: Outlook profiles that will not connect cleanly to Exchange Online, add-ins that require newer API sets, or OneDrive sync quirks. None of these get fixed.
4. Macros and add-ins
Vendors of line-of-business add-ins (accounting exports, CRM connectors, PDF tools) usually drop support for Office versions that Microsoft no longer supports. If a vendor's helpdesk asks for your Office build number and you say 2021, expect to be told to upgrade first.
Your upgrade options
Whichever route you take, Microsoft's own recommendation is to move to a supported version. In practice there are three routes.
| Option | Licence model | Supported until | Best for |
|---|---|---|---|
| Office 2024 (Home, Home & Business) | One-time purchase, one device | 9 October 2029 | Home users, sole traders who need the core apps |
| Office LTSC Professional Plus 2024 | One-time purchase, per device | 9 October 2029 | Offices that need Access and Outlook, and want no subscription or cloud dependency |
| Microsoft 365 (Personal, Family, Business plans) | Subscription, per user | As long as you subscribe | Teams that co-author in real time, need cloud storage and email, or want new features monthly |
Option A: Office 2024 or Office LTSC 2024 (one-time licence)
This is the like-for-like replacement. Office 2024 keeps the same 16.0 major version and Click-to-Run installer as 2021, so your existing Group Policy settings, registry tweaks under HKCU\Software\Policies\Microsoft\Office\16.0, macros and most add-ins carry straight over. You get five years of security updates from release, finishing in October 2029, and no recurring cost.
The trade-offs: no new features after launch, no Publisher, no preinstalled Teams, and each licence covers one device. If you share a household or small office, a multi-device option such as Office 2024 Pro Plus for 3 devices keeps things simple. Mac users should look at Office 2024 Home and Business for PC/Mac instead, because Professional Plus is Windows-only.
Option B: Microsoft 365
Microsoft 365 Apps are never "end of support" as long as you stay on a supported update channel. You get continuous feature updates, OneDrive storage, installs on several devices per user and, on business plans, Exchange Online mailboxes and Teams. If your team already relies on co-authoring, shared mailboxes or SharePoint, Microsoft 365 is usually the better fit, and Microsoft names it as its primary recommendation. The cost is ongoing, and some people prefer software that does not change its interface every few months. We cover the trade-off in more depth in Microsoft 365 vs Office 2021: the differences explained. The reasoning applies just as well to 2024.
Option C: Stay on Office 2021 (with eyes open)
For an offline PC that never opens email attachments, such as a machine that only drives a label printer, staying put can be a reasonable short-term decision. If you do, make sure the final October 2026 update is installed, enable Protected View for all three categories (File → Options → Trust Center → Trust Center Settings → Protected View), block macros from the internet, and put a date in the diary to revisit the decision. For any PC used for email and everyday documents, we don't recommend it.
Migration checklist: Office 2021 to Office 2024
The upgrade itself takes about 20 minutes per PC. The preparation is what saves you a call to support afterwards.
- Check your current version. Open Word → File → Account. Note the product name (for example "Office LTSC Professional Plus 2021" or "Office Home & Business 2021") and whether it says 32-bit or 64-bit under About Word.
- Inventory add-ins and macros. In each app, open File → Options → Add-ins and screenshot the COM add-ins list. Ask vendors whether their add-in supports Office 2024. Keep the same bitness, because 32-bit COM add-ins will not load in 64-bit Office.
-
Back up Outlook data. For POP or IMAP accounts, note the location of your
.pstfiles (usuallyDocuments\Outlook Files). Export signatures from%APPDATA%\Microsoft\Signatures. -
Export Publisher files. Save every
.pubyou still need as PDF or Word. - Uninstall Office 2021 cleanly. Use Settings → Apps → Installed apps, then restart. Two Click-to-Run versions side by side cause the familiar "We can't install" conflict. If the uninstall fails, Microsoft's Support and Recovery Assistant can remove leftovers.
- Install and activate Office 2024. Follow our Office 2024 Pro Plus download, install and activation guide. Enter the key when prompted, or later under File → Account → Change Product Key.
-
Re-test the essentials. Open a macro-enabled workbook, send a test email, check default file associations, and confirm that templates in
%APPDATA%\Microsoft\Templatesstill appear. - Record the licence. Store the product key and order email together with the PC's name. Future-you will be grateful.
If you get stuck on downloading or activation, our software download and activation hub brings all of our install guides together in one place.
Don't forget the operating system
Windows 10 reached end of support in October 2025. Putting a supported Office version on an unsupported OS only solves half the problem. If any PC in the office is still on Windows 10, plan the Windows 11 move alongside the Office upgrade so that both stay patched to the same standard.
Frequently asked questions
Will Office 2021 stop working after 13 October 2026?
No. The apps keep opening, editing and saving files, and your activation remains valid. What stops is security updates, bug fixes and Microsoft technical support.
Is there an extended support option for Office 2021?
No. Microsoft has not offered Extended Security Updates for Office 2021 or Office LTSC 2021. The October 2026 update is the last one.
Can I upgrade from Office 2021 to Office 2024 for free?
No. Office 2024 is a separate product with its own licence. Your Office 2021 key will not activate it. You uninstall 2021 and then install and activate 2024 with a new key.
How long will Office 2024 be supported?
Office 2024 and Office LTSC 2024 are both supported until 9 October 2029. That gives roughly three more years from today than you have left on 2021.
Can Office 2021 still connect to Outlook.com or Exchange Online?
Usually yes, at least for now. Microsoft does not block it, but that connectivity is no longer supported after 13 October 2026. Problems that appear later may not be fixed.
Do Project 2021 and Visio 2021 lose support too?
Yes. Project 2021, Visio 2021 and their LTSC versions reach end of support on the same date. Their 2024 versions are the direct successors.
Our recommendation
If your team already lives in Teams, SharePoint and shared mailboxes, Microsoft 365 is the natural next step. If you bought Office 2021 because you wanted desktop apps you own outright, with no subscription and no surprise interface changes, Office 2024 Professional Plus is the direct successor. It has the same familiar apps, the same file formats and the same policies, plus security updates until October 2029. Upgrade before 13 October, so the move happens on your schedule rather than after an incident.
Related reading
| Resource | Why read it |
|---|---|
| Office 2024 Pro Plus install guide | Step-by-step download, install and activation |
| Microsoft 365 vs Office 2021 | Subscription vs one-time licence, explained |
| Download and activation hub | All of our install guides in one place |