Office 2021 support ends October 13: what to check before upgrading

Office 2021 is approaching the end of its supported life. Before buying a replacement, check your installed edition and make a short list of the documents and features you depend on.

Microsoft says support for Office 2021 ends on October 13, 2026, with no extension or extended security updates. The deadline is three days away. Its support notice says the apps may keep working, but Microsoft will stop supplying technical support, bug fixes and security fixes.

So an application opening normally after the deadline is not proof that it remains supported. For a home user, this is a reason to plan an upgrade even if Word and Excel still do everything needed. For a work or school installation, Microsoft directs users to their IT help desk; the organization may already have an upgrade plan.

First, find out which Office you have

Do not decide from the icon on your taskbar. Open Word and look at the product information. On Windows, Microsoft’s version-identification guide points to File > Account, with About Word providing version and build details. On a Mac, use the Word menu and choose About Word to see the version and licence information.

Write down the product name as well as the version number. That gives you something precise to compare with a support notice or send to an IT administrator. A subscription installation and a one-time purchase should not be treated as interchangeable simply because both include Word.

If someone else manages the computer, ask them to confirm the edition before changing it. Include the name of any add-in you rely on and the file types you use most often. “I use a spreadsheet with macros every Friday” is more useful than “I need Excel.”

Compare the purchase models before the features

Microsoft’s upgrade guide lists two routes for owners of a non-subscription edition: a Microsoft 365 subscription or a newer one-time purchase. Office Home 2024 and Office Home & Business 2024 are its current one-time-purchase examples. Those editions are installed on one device and receive fixes during their supported period, without the continuing new features of Microsoft 365.

Check the exact plan and included applications before paying. Microsoft 365 Basic, for example, does not include the desktop Word, Excel and PowerPoint apps. A familiar brand name on a checkout page is not enough to establish that the product replaces your existing setup.

Start your comparison with a few practical questions: How many computers need the software? Is offline desktop editing essential? Do you need Outlook, or mainly documents and spreadsheets? Check current regional pricing once you know which products meet those needs; this guide does not quote a price or recommend a particular paid plan.

Test the files that would be painful to fix

Before installing anything, check the new version’s system requirements. Microsoft also advises considering a backup of Outlook data files where Outlook is included. Follow the linked upgrade instructions for your platform instead of uninstalling the old version as an automatic first step.

Our suggested preparation is a small test folder containing copies of real work. Choose a document with awkward formatting, a spreadsheet you regularly calculate with, and any presentation you must deliver soon. Keep the originals untouched.

• Open the copies in the replacement application and check page breaks, fonts and printed output.
• In spreadsheets, compare important results with the original and check any links to other files.
• If you use macros or add-ins, confirm compatibility with their provider or your IT team.
• Save, close and reopen a test copy. If you share files, ask a regular recipient to check it too.

If a test fails, note the file, the affected feature and what changed. Send those details to the software provider or your IT team before switching your everyday work to the new application.

For a managed work computer, keep IT in the loop

Office LTSC 2021 has the same October 13 end-of-support date. Microsoft’s commercial lifecycle notice, updated April 23, lists Microsoft 365 Apps and Office LTSC 2024 as upgrade paths for organizations. That is a deployment decision for the people managing the installation, not a reason for an employee to buy a personal licence.

If you contact the help desk this week, send your product details, the files or add-ins that need testing, and any upcoming work deadline. Ask when the replacement will be available and where to report a compatibility problem.

Checked October 10, 2026 against Microsoft’s support documentation. This article was prepared with AI assistance. The illustrations are AI-generated; they do not show an actual Office interface.