Office 2021 Support Ends in October: Is Your Business Ready?
Microsoft will end support for Office LTSC 2021, Project LTSC 2021 and Visio LTSC 2021 on 13 October 2026.
After this date, these applications will no longer receive security fixes, software updates or technical support from Microsoft.
The programs will not necessarily stop opening on 14 October. That does not mean it is safe or sensible to continue using them indefinitely.
Why unsupported Office software matters
Business documents regularly contain customer details, financial information, quotations, contracts and confidential correspondence.
Once a version of Office stops receiving security updates, newly discovered vulnerabilities may remain uncorrected. Compatibility with email systems, document formats and other business applications may also deteriorate over time.
Unsupported software can create problems for:
- Cyber insurance requirements
- Customer and supplier security questionnaires
- Data-protection risk management
- Compatibility with other Microsoft services
- Reliable document sharing
- Technical support and incident recovery
The installations businesses frequently overlook
The main office computers may already use Microsoft 365 while less visible devices remain on older perpetual licences.
These can include:
- Reception and accounts computers
- Shared workshop or warehouse PCs
- Laptops kept for occasional remote work
- Project-management computers
- Machines running specialist integrations
- PCs inherited through a business acquisition
- Devices used by temporary or seasonal staff
Project and Visio installations can be particularly easy to miss because they may only be used by one employee.
Do not replace software without checking the workflow
Moving to Microsoft 365 is the normal route for many SMEs, but it should not be treated as a blind installation exercise.
A proper review should establish which applications are installed, who uses them, which documents and templates they depend on, and whether macros or specialist integrations are involved.
The appropriate replacement may differ between users. Some businesses need desktop applications, while others may be adequately served by browser-based tools.
Microsoft Software Lifecycle Review
Joe Hunter IT provides software and cybersecurity reviews for businesses across Ireland and the UK.
A Microsoft Software Lifecycle Review can identify:
- Unsupported or soon-to-be-unsupported applications
- Devices missing from the normal IT inventory
- Users who need desktop rather than browser applications
- Dependencies on macros, templates and integrations
- Suitable Microsoft 365 licensing options
- Security and compatibility risks
- A practical migration sequence that reduces disruption
The purpose is not to sell every employee the most expensive subscription. It is to identify what the business actually uses and establish a supported route forward.
Check before 13 October
If your business uses a perpetual version of Office, Project or Visio, it is worth checking the exact edition now.
Contact Joe Hunter IT at joe@joehunterit.com or visit joehunterit.com to arrange a Microsoft software review.
Source: Microsoft September 2026 Partner Center announcements