Is Office 2021 Still Safe to Use After End of Support?

Is Office 2021 still safe? Only with care, and less so each month. Since support ended on 13 October 2026, Microsoft no longer patches newly found security flaws in Office 2021, so documents from email or the web carry growing risk. On an offline or tightly controlled PC, short-term use is reasonable. On a daily, internet-connected work PC, plan to replace it.

Is Office 2021 safe to use after end of support?

Office 2021 is not unsafe overnight, because it received its final security update in October 2026 and is fully patched up to that point. The risk comes afterwards: any vulnerability discovered from now on stays open permanently, so the software becomes steadily less safe the longer you keep it, especially if you open files from other people.

Microsoft's end of support notice for Office 2021 warns that continuing to use it "could expose yourself to serious and potentially harmful security risks", and confirms there is no extension.

The overall decision, including all five upgrade routes, is covered in our Office 2021 end of support guide. This article focuses on the security question.

How do I check if I am running Office 2021?

Open Word, select File > Account and read the name under Product Information; it shows the edition, such as Office Professional Plus 2021 or Office LTSC Standard 2021. If it says Microsoft 365 or Office 2024, you are on a supported version and this end-of-support warning does not apply.

The same screen shows the version and build under About Word. Note both before updating, so you can confirm the final update installed. Our guide to checking Office activation status shows where each detail appears and how to find the product key.

Visio 2021 and Project 2021 are separate products with their own licences. Check them the same way, because they reached end of support on the same date.

Does Office 2021 still get security updates?

No. Office 2021 and Office LTSC 2021 received their last security update on 13 October 2026, the October Patch Tuesday. Microsoft does not sell Extended Security Updates for Office, unlike Windows 10, so there is no paid route to further official fixes for Office 2021.

Before relying on Office 2021 at all, confirm that the final update is installed:

1. Open Word or Excel and select File > Account.
2. Choose Update Options > Update Now and let it finish.
3. Close and reopen the app, then check the version number under About.

Volume-licensed installs managed through WSUS or Configuration Manager should show the October 2026 update as installed in the management console.

What are the real risks of running unsupported Office?

The main risk is malicious documents: Word, Excel and PowerPoint files crafted to exploit a flaw when opened or previewed, delivering malware or stealing data. Office files are a common route for phishing attacks, and once flaws in Office 2021 stop being fixed, attackers can rely on them staying open on every unpatched copy.

• Malicious attachments: a document arriving by email exploits an unpatched parsing bug.
• Macro abuse: users are tricked into clicking Enable Content, running VBA code that installs malware.
• Outlook exposure: previewing a crafted message or attachment can be enough for some vulnerability types.
• Compatibility drift: Microsoft no longer tests Office 2021 against its cloud services, so sync and sign-in problems may go unfixed.

Cause and effect: when Microsoft patches a flaw in Office 2024 or Microsoft 365, the published fix can help attackers locate the same weakness in older code. If Office 2021 shares that code, it stays exploitable, and the patch effectively becomes a map.

Does Office 2021 block macros from the internet?

Not by default in the way Microsoft 365 does. Microsoft's guidance on macros from the internet says the stricter default that blocks VBA macros in downloaded files applies to Microsoft 365 Apps, and that perpetual versions such as Office LTSC 2021 keep the older "Enable Content" prompt, which users can click through.

You can tighten this yourself in each app:

1. Go to File > Options > Trust Center > Trust Center Settings.
2. Under Macro Settings, choose Disable all macros with notification or Disable all macros without notification.
3. Under Protected View, keep all three options ticked so internet files, unsafe locations and Outlook attachments open read-only.

What we commonly see: users switch off Protected View because the yellow bar is annoying, then forget. On an unsupported Office version, it is one of the most useful protections left.

How can I reduce the risk if I keep Office 2021 for now?

Reduce the risk by limiting what Office 2021 opens and keeping everything around it fully patched: install Office 2021's final update, keep Windows and Microsoft Defender current, leave macros disabled and Protected View on, avoid opening unexpected attachments, and use a standard rather than administrator account for daily work.

• Open untrusted files elsewhere: preview unknown attachments in Office on the web rather than the desktop app.
• Use a supported OS: Windows 11 with current updates closes many exploit paths; our Defender vs paid antivirus guide explains what built-in protection covers.
• Back up regularly: keep an offline or versioned backup of documents in case malware gets through.
• Set a deadline: decide now when you will replace Office 2021, rather than staying indefinitely.

Third-party "micropatch" services sell unofficial fixes for some critical flaws in out-of-support Office versions. They can bridge a short gap but are not Microsoft updates.

Is Office 2021 safe for business use after end of support?

For most businesses, no longer. Running unsupported software on PCs that handle client data, payments or regulated information can conflict with cyber-insurance conditions, security frameworks and audit requirements, many of which expect vendor-supported software. Businesses should treat Office 2021 as a migration task with a firm date rather than an acceptable steady state.

Microsoft's connectivity policy for Office also lists 13 October 2026 as the last supported date for Office LTSC 2021 to connect to Microsoft 365 services. Firms using Exchange Online with Outlook 2021 are now outside that support.

Advanced nuance: organisations that chose Office LTSC 2021 for a fixed feature set can keep that model with Office 2024 Pro Plus LTSC, supported until 9 October 2029, which also disables ActiveX controls by default. Multi-seat buyers can use the business quote form.

Office 2021 vs Office 2024: is the upgrade worth it for security?

Yes. Security is the strongest reason to upgrade, because Office 2024 receives Microsoft security fixes until 9 October 2029 while Office 2021 receives none. Office 2024 looks and works much like 2021, so there is little retraining, and it adds newer features and a refreshed design alongside those three extra years of protection.

For Windows users replacing Office Professional Plus 2021, Office 2024 Professional Plus for Windows keeps the same apps including Access; see the current price on the product page. If you are weighing a subscription instead, our Office 2024 vs Microsoft 365 cost comparison works through five-year totals.

Frequently asked questions

Can I still use Office 2021 in 2027?

Yes, Office 2021 will still run and stay activated in 2027. It simply receives no security updates, so every flaw found after October 2026 remains unpatched. Use it in 2027 only on a low-risk PC with hardened settings, and treat it as temporary while you move to a supported version.

Is Outlook 2021 safe to use for email?

Outlook 2021 carries the highest risk of the Office 2021 apps, because email is the main route for malicious attachments and links. If you keep it, leave Protected View on for attachments and avoid previewing unexpected files. Outlook on the web or a supported Outlook version is the safer choice for daily email.

Will antivirus protect me if I keep Office 2021?

Antivirus helps but does not replace security updates. Microsoft Defender and other tools detect many known malicious documents, yet a new exploit can work before detection signatures exist. Antivirus plus an up-to-date Windows reduces risk; it does not make an unpatched Office version as safe as a supported one.

Is Office 2021 for Mac still safe?

Office 2021 for Mac and Office LTSC 2021 for Mac also reached end of support on 13 October 2026, so the same reasoning applies. macOS adds some protections, but malicious documents target Office itself. Mac users can move to Office 2024 Home or Home & Business, or to Microsoft 365.

Is it safe to buy an Office 2021 licence now?

It is legal but rarely sensible. A new Office 2021 licence starts life already out of support, with no security updates ahead. Unless a specific legacy system requires 2021, buy Office 2024 instead, which costs a similar amount at most resellers and is supported until October 2029.

Related guides

• Office 2024 vs Office 2021: what is new and should you upgrade?
• Office 2024 crack and KMS activators: the real risks
• Completely uninstall old Office before installing Office 2024
• Microsoft 365 price increase 2026: cheaper ways to get Office

Links in this guide