Microsoft will end support for Office 2021 on 13 October 2026. After that date there are no more security fixes, bug fixes or technical support, and Microsoft has said there will be no extension and no paid extended security updates. Word, Excel and Outlook will still open, but every newly discovered weakness in them will stay unpatched. If your business bought Office as a one-off purchase in the last few years instead of subscribing, there is a fair chance this is the version on your PCs.
What is changing and when
Microsoft's support article, End of support for Office 2021, sets out what stops after 13 October 2026:
- technical support, bug fixes and security fixes, including fixes for vulnerabilities found later
- Office 2021 software updates
- phone and chat technical support
- updates to help content, most of which will be retired.
The same date appears on Microsoft's list of products ending support in 2026. Microsoft publishes its lifecycle dates in US Pacific time.
| Product | Who typically has it | Date |
|---|---|---|
| Office 2021 (Home and Student, Home and Business, Professional, including the Mac editions) | Businesses and households that bought Office once, often with a new computer | 13 October 2026 |
| Individual 2021 apps: Word, Excel, PowerPoint, Outlook, OneNote, Access, Publisher, Project and Visio | Anyone who bought a single app | 13 October 2026 |
| Office LTSC 2021 and its apps, including Skype for Business LTSC 2021 | Organisations with volume licences | 13 October 2026 |
The desktop versions of Project and Visio share the end of support date of the Office suite they belong to, so they need to be on your list as well.
Who is affected
You are affected if any computer in the business runs Office 2021 or Office LTSC 2021. This is common in small offices that preferred to pay once: an accounting practice that bought Office with each new laptop, a builder's site office with two desktops, a retail back office with one shared PC.
You are not directly affected if everyone uses Microsoft 365 Apps, the subscription version of Office that comes with many Microsoft 365 business plans. Microsoft describes it as continuously updated. There is one catch for subscribers on older computers. Microsoft's guidance on Microsoft 365 Apps and Windows 10 says those devices will keep receiving security updates until 10 October 2028 but will stop receiving new features once Version 2608 is released, and that support staff will ask customers to move to Windows 11 if a problem occurs only on Windows 10.
If you are not sure which version a computer has, Microsoft's support article links to a page for finding the details of your Office version. Purchase records and licence keys will also tell you.
Why running Office 2021 after October is a risk
Microsoft's own wording is that the apps may continue to function but that you could expose yourself to "serious and potentially harmful security risks". The reason is practical. Office is the software that opens files from outside the business: invoices, quotes, resumes, spreadsheets from suppliers. Attackers send malicious documents because they know staff will open them. While a product is supported, weaknesses are patched as they are found. Once support ends, each new weakness stays open for as long as the software is in use.
There is a quieter cost too. With no bug fixes and no support line, a fault in Outlook or Excel after October is yours to work around.
The options
Microsoft's upgrade guidance for older versions of Office presents two paths for organisations. A third suits very small offices and households.
| Option | How it is licensed | Updates | Where it fits |
|---|---|---|---|
| Microsoft 365 Apps | Subscription, per user, included in many Microsoft 365 business plans. A user can install it on more than one device | Continuously updated, with new features as often as monthly | Most offices, especially where staff also need email, Teams and OneDrive |
| Office LTSC 2024 | One-time purchase through a volume licence agreement, one device per licence | Fixes only. Features are fixed at the September 2024 release | Microsoft says it is designed for specific scenarios, such as regulated devices that cannot accept feature updates and systems that cannot connect to the internet |
| Office 2024 (Home, Home and Business) | The newer release in the same product line as Office 2021 Home and Business | Microsoft's lifecycle page lists it as supported until October 2029 | A sole operator or a very small office that does not need the Microsoft 365 services |
| Stay on Office 2021 | No change | None after 13 October 2026 | Not recommended on any computer that opens email or files from outside |
Two details from Microsoft's documentation are worth knowing before you choose. Its list of supported operating systems for Office LTSC 2024 includes Windows 11 but, for Windows 10, only the long-term servicing releases, so an older PC may need upgrading or replacing first. And Microsoft Publisher is not included in Office LTSC 2024, because Microsoft is retiring Publisher and will not support it after October 2026. If anyone in the business still produces flyers or price lists in Publisher, plan a replacement for those files.
We have left prices out on purpose. Licensing costs depend on the plan, the number of users and how you buy, and they change. Ask for a written comparison based on your own user list.
A checklist before 13 October
- List every computer and its Office version. Include Macs, shared PCs, home computers used for work, and any copies of Project or Visio.
- Note the Windows version on each. The Office decision and the Windows decision affect each other, so make them together.
- Find what depends on Office. Microsoft recommends testing business-critical macros, add-ins and complex documents and spreadsheets before moving. Think of the quoting spreadsheet, the mail merge for statements and the accounting add-in.
- Decide user by user. Staff who need shared mailboxes, Teams and file sharing suit a subscription. A workshop PC that only prints job sheets may not.
- Check where email and files live. If the move to Microsoft 365 also means moving mailboxes and shared folders, treat that as a small project with its own plan and a backup taken first.
- Remove the old version properly. Microsoft's guidance is to uninstall previous versions of Office before installing the new one.
- Pick your timing. Avoid month-end, payroll runs and BAS deadlines, and upgrade one or two computers first to catch surprises.
- Keep records. File the licences, the account that owns them and the date each computer was done.
Comingwave is a technology company that provides technology and business solutions to small and medium enterprises. Our managed IT support service covers software audits, upgrades and ongoing updates. Our cloud migration and hosting service covers moving email and files to a cloud platform, and our IT consulting service can help you compare licensing options against how your staff work. For a written quote before any work starts, send us an enquiry.
Key takeaways
- Support for Office 2021 and Office LTSC 2021 ends on 13 October 2026.
- Microsoft has said there will be no extension and no extended security updates for Office 2021.
- The apps keep working, but without security fixes, bug fixes or technical support.
- The main paths are Microsoft 365 Apps by subscription, or Office LTSC 2024 or Office 2024 as one-off purchases.
- Check Windows versions, macros, add-ins and Publisher files before you choose.
Frequently asked questions
Will Office 2021 stop working on 13 October 2026?
No. Microsoft says the apps may continue to function. What ends is security fixes, bug fixes, software updates and technical support, which is why Microsoft recommends upgrading.
Can I pay for extended security updates for Office 2021?
No. Microsoft's support article states there will be no extension and no extended security updates for Office 2021.
Is Office LTSC 2021 affected as well?
Yes. Microsoft lists Office LTSC 2021, the volume licensed edition, with the same end of support date of 13 October 2026.
Do Microsoft 365 subscribers need to do anything?
Not for this deadline, because Microsoft 365 Apps is continuously updated. Subscribers on Windows 10 should still plan a move to Windows 11, as feature updates for Microsoft 365 Apps on Windows 10 are ending.
Should a small office choose Microsoft 365 or a one-time purchase?
It depends on how you work. Microsoft's guidance concentrates on the subscription and describes Office LTSC 2024 as designed for specific scenarios, such as devices that cannot take feature updates. Compare both against your user list before deciding.