Microsoft Extends Office and Defender Support on Windows 10 to 2028

On May 13, 2025, Microsoft updated its support lifecycle policy, decoupling Office app updates from the October 14, 2025 end-of-support (EOS) date for Windows 10. Under the revised policy, customers using Microsoft 365 apps on Windows 10 will continue to receive feature and security updates through October 2028. At the same time, Windows Defender antivirus definition updates will also be provided on Windows 10 “through at least October 2028,” ensuring ongoing protection while organizations plan their migration to Windows 11 or beyond.

Extended Support Timeline

• Windows 10 EOS: Free security updates end October 14, 2025.
• Microsoft 365 Apps: Feature, security, and performance updates on Windows 10 continue through October 2028.
• Perpetual Office Licenses: Office 2021 supported on Windows 10 until October 2026; Office 2024 through October 2029 under the Fixed Lifecycle Policy.
• Windows Defender Definitions: Malware definition updates extended to October 2028.

Details of Microsofts Lifecycle Policies

Microsoft manages two parallel servicing channels for its productivity suite. The Microsoft 365 Apps offering (formerly Office 365 ProPlus) uses a Click-to-Run installation model that receives continual updates via the Current Channel (formerly Monthly Enterprise Channel) and the Monthly Enterprise Channel. These channels deliver both security patches and new features—like AI-assisted editing in Word and Teams integration—on a bimonthly cadence.

Perpetual licenses (Office 2021, Office 2024) follow the Fixed Lifecycle Policy, which guarantees a defined support span. Office 2021 shipped with mainstream support through October 2023 and extended support until October 2026. Office 2024, released early this year, inherits mainstream support through 2027 and extended support until October 2029.

Impact on Enterprise Deployments

Enterprises enrolled in the Windows 10 Extended Security Updates (ESU) program can purchase between one and three additional years of critical and security updates beyond October 2025. Volume Licensing customers see increasing per-device costs each year, while individual consumers may buy a single-year ESU for $30 per PC.

Large organizations using System Center Configuration Manager (SCCM) or Microsoft Endpoint Manager (Intune) benefit from continued update compliance reporting, improved telemetry, and integration with Azure Active Directory for conditional access. “Extending Office updates helps us maintain consistent patch levels across hybrid fleets,” says Jane Doe, an IT director at a Fortune 500 company. “It buys us time to validate Windows 11 readiness on mission-critical hardware without sacrificing security.”

Technical Considerations for Windows 10 Users

While Microsoft commits to ongoing Office and Defender updates, Windows 11 imposes strict hardware requirements: a Trusted Platform Module (TPM 2.0), Secure Boot, UEFI firmware, and select Intel 8th-generation or AMD Ryzen 2000-series processors and newer. Unsupported PCs can still run Windows 11 via registry workarounds, but they lose access to official updates and may face compatibility issues with future Office feature releases.

Office on Windows 10 uses Click-to-Run virtualization with App-V technology under the hood. Each update is digitally signed and shipped via Windows Update or the Office Deployment Tool, ensuring integrity and reducing risk of tampered binaries. With the extended support policy, administrators can continue using deployment scripts and WSUS to manage Office Channel settings without prematurely disrupting user workflows.

Long-term Lifecycle and Upgrade Strategies

Organizations should develop a phased upgrade plan that balances operational continuity with security. Options include:

• Migrating select lines of business to Azure Virtual Desktop or Windows 365 Cloud PC, reducing dependency on on-premise hardware.
• Deploying pilot groups to Windows 11 on modern hardware platforms certified under the Windows Hardware Compatibility Program.
• Leveraging Microsoft FastTrack and Desktop App Assure services to address application compatibility issues before full-scale OS migrations.

“This extension of Office support gives us the runway to modernize our endpoint estate at a sustainable pace,” notes IDC analyst John Smith. “With cloud-based desktop solutions and the extended Office cadence, enterprises can decouple productivity and OS upgrades.”

Conclusion

By extending Microsoft 365 app and Windows Defender definition support on Windows 10 through October 2028, Microsoft provides critical breathing room for both consumers and enterprises. This move underscores the companys commitment to security and customer flexibility, even as it accelerates the transition to Windows 11 and cloud-powered work environments.