Office LTSC 2021 Reaches End of Support as Microsoft Cuts Security Updates

Microsoft is officially ending support for Office LTSC 2021, Visio LTSC 2021, and Project LTSC 2021 today, October 13, 2026. Organizations still using these products will no longer receive security updates, potentially exposing their systems to new vulnerabilities.

As Microsoft previously warned, the deadline marks the end of security patches and technical support for these Office versions.

Microsoft also confirmed the deadline in message MC1472429 in the Microsoft 365 Admin Center, urging organizations to migrate to supported alternatives.

Microsoft recommends upgrading to Microsoft 365

Microsoft recommends that organizations switch to Microsoft 365 or Office 365 subscriptions that include Microsoft 365 Apps.

For enterprise customers, Microsoft recommends Microsoft 365 E3, Office 365 E3, or Microsoft 365 Apps for enterprise.

Businesses with fewer than 300 users can choose Microsoft 365 Business Premium, Business Standard, or Microsoft 365 Apps for business.

Unlike Office LTSC 2021, Microsoft 365 Apps receives regular feature improvements and security updates, providing access to the latest versions of Word, Excel, PowerPoint, and other Office applications.

Office LTSC 2024 remains an alternative

Organizations that prefer traditional Office installations without relying on cloud connectivity can upgrade to Office LTSC 2024.

This version supports on-premises deployments and will continue receiving security updates until October 2029.

However, Office LTSC 2024 also has a fixed support lifecycle, meaning organizations will eventually need to plan another upgrade.

What happens if you continue using Office LTSC 2021?

Office LTSC 2021 applications will continue to work after October 13, but Microsoft will no longer provide security fixes or technical support.

This could leave organizations vulnerable to newly discovered security threats. Unsupported software can also introduce compliance concerns and compatibility issues with newer systems.

Microsoft has published official upgrade guidance to help IT administrators migrate from older Office releases to Microsoft 365 Apps.

Meanwhile, Microsoft is preparing other changes across its ecosystem. The company recently confirmed that Microsoft 365 Targeted Release is going away in 2027.

Windows users also face another approaching deadline, as Windows 11 23H2 reaches the end of support in 30 days.

Via Neowin