Microsoft Is Cutting Off Office 2021 Support, but There’s a Pricy Way Around It

Microsoft Office 2021 end-of-support arrives on October 13, 2026, but users who cannot upgrade immediately will have another option for receiving security patches.

Office LTSC 2021 will stop receiving Microsoft security updates after that date. Microsoft will not offer security updates for the productivity suite after support ends, prompting users to seek third-party security solutions.

Microsoft wants Office 2021 users to upgrade

Microsoft recommends moving to Microsoft 365 or Office 2024 before Office LTSC 2021 reaches the end of support.

After October 13, Microsoft will no longer provide security updates, bug fixes, or official servicing for Office 2021.

Unlike Windows 10, Office 2021 will not receive an official ESU program. Microsoft recently extended Windows 10 ESU enrollment until October 2027, but it has no similar plan for Office 2021.

Organizations that rely on Office 2021 therefore need to upgrade or accept the security risks that come with running unsupported software.

0patch will support Office 2021 for at least three more years

Acros Security says its 0patch service will provide extended security support for Office 2021 once Microsoft’s support ends.

Coverage will begin after October 13, 2026, with 0patch promising critical security patches for at least three additional years.

The company could extend that period if enough customers continue using Office 2021.

There is already precedent for much longer support. 0patch says it is currently in its sixth year of providing security fixes for Office 2010.

0patch uses micropatches instead of modifying Office files

0patch plans to focus on critical vulnerabilities that attackers could exploit after Microsoft stops patching Office 2021.

Instead of replacing Microsoft’s binaries, the service applies small micropatches directly to running processes in memory.

This approach offers several advantages: Office’s original executable files remain unchanged, and administrators can quickly remove a problematic micropatch.

That could make 0patch useful for organizations that have legacy applications, workflows, or compatibility requirements that prevent an immediate move to Office 2024 or Microsoft 365.

Office 2021 coverage requires 0patch PRO or Enterprise

0patch will offer Office 2021 security coverage through its PRO and Enterprise subscriptions.

The Enterprise plan currently costs €34.95 plus tax per computer per year.

It also includes features aimed at businesses managing multiple PCs, including central management, support for multiple users and administrative roles, computer groups, group-based patching policies, and single sign-on.

0patch does not replace full Microsoft support

The service has an important limitation. 0patch provides security patches, not complete technical support for Office 2021.

Customers should not expect new features, normal bug fixes, compatibility improvements, or general Microsoft Office support.

For users ready to leave Office 2021 instead, Microsoft has also highlighted several notable Office 365 features that could make the subscription platform a more attractive upgrade.