Microsoft has posted a formal 90-day advance notice that two distinct versions of Windows—the current Windows 11 Home and Pro release (version 24H2) and the decade-old Windows 10 Enterprise LTSB 2016—will stop receiving security updates on the same date: October 13, 2026. The shared deadline obscures a vast difference in urgency and upgrade complexity between a routine feature update and a painstaking migration of specialized legacy hardware.

What Just Happened

According to Microsoft’s Windows Release Health documentation, after October 13 devices running Windows 11 24H2 Home or Pro will no longer receive monthly security patches, preview updates, time-zone data corrections, known-issue fixes, or technical support. The same cutoff applies to Windows 10 Enterprise LTSB 2016 (version 1607, build 14393), as confirmed by the company’s lifecycle fact sheet.

For LTSB 2016, Microsoft has also published a dedicated set of instructions to enroll in a paid Extended Security Updates (ESU) program. The ESU offer can deliver Critical and Important security fixes beyond the end-of-support date, but it requires device preparation, activation with a Multiple Activation Key (MAK), and a per-device subscription.

What It Means for You

The practical impact splits sharply depending on which Windows you run.

For Windows 11 24H2 Home and Pro Users

If your PC is already on Windows 11 24H2 and you keep automatic updates enabled, you are likely to be offered the next feature update—version 25H2—well before the deadline. Microsoft has stated that unmanaged Home and Pro systems will receive the 25H2 upgrade automatically, subject to normal rollout controls. In most cases, the process should be seamless.

But assuming an automatic update will arrive on time can be risky. Safeguard holds can block the offer if Microsoft detects a compatibility issue with your hardware or software. Low disk space, infrequent use, or a paused Windows Update can also leave the machine stranded. A quick check today is far simpler than troubleshooting an unsupported device later.

For users who prefer to stay on an older build, note that the timer is firm. After October 13, any newly discovered vulnerability will remain unpatched on 24H2 Home and Pro, increasing the attack surface every month.

For IT Administrators Managing 24H2 Fleets

Organizations that run Windows 11 24H2 Enterprise or Education editions have an additional year of support—until October 12, 2027—and can therefore take more time to validate their next servicing baseline. But for Home and Pro devices in the fleet, the 24-month servicing window closes on the same October 13 date.

The real question for IT is not whether 24H2 can remain in service until the deadline, but whether the organization has already chosen its next servicing target. Microsoft’s current supported-version table lists Windows 11 version 25H2 (support through October 12, 2027 for Home/Pro) and the even newer 26H1, build 28000 (support through March 14, 2028 for Home/Pro). Administrators should decide now which release will become their standard, begin pilot testing, and ensure deployment tools are ready. Stalling will only compress the migration timeline.

For Anyone Running Windows 10 Enterprise LTSB 2016

This is where the deadline bites hardest. LTSB 2016 was designed for fixed-purpose devices—medical imaging consoles, factory control stations, ATMs, point-of-sale terminals, kiosks, and similar roles where feature churn is undesirable. Many of those machines have been in place for nearly a decade, often tied to custom drivers, regulatory certifications, or applications that have never been revalidated on a newer OS.

Replacing or upgrading such a device is not a click-through process. It can involve hardware procurement, application vendor support checks, driver availability, and lengthy testing cycles. The ESU program offers a bridge, but it is a paid, per-device subscription that must be activated before October 13. Even with ESU, Microsoft will provide only security fixes—no bug fixes, no technical support, and no feature improvements.

How We Got Here

Microsoft’s modern lifecycle policy gives Windows 11 Home and Pro editions 24 months of servicing, while Enterprise and Education get 36 months. That is why the cutoff applies only to the consumer and small-business editions of 24H2; the enterprise editions remain in support until 2027. The Windows 11 24H2 release originally rolled out in late 2024, so its 24-month clock expires in October 2026.

Windows 10 LTSB 2016 arrived on August 2, 2016, under the old Long-Term Servicing Branch model. It received five years of mainstream support through October 12, 2021, and then another five years of extended support, which now ends on October 13, 2026. The entire Windows 10 family, except for certain LTSC editions, hit general end of support in October 2025. For LTSB 2016, Microsoft introduced an ESU add-on that can stretch security coverage for up to three additional years, mirroring similar programs for other Windows 10 editions. However, each year of ESU requires a separate activation key and may become more expensive over time.

What to Do Now

If You Have a Windows 11 24H2 Home or Pro PC

  1. Open Settings > Windows Update and install all available cumulative updates.
  2. Look for a notification that a feature update is available—likely Windows 11 version 25H2. If you see it, schedule the installation during a convenient time window.
  3. If no feature update appears, check for known safeguard holds. The Windows Update page sometimes lists a message explaining why the update isn’t offered yet. Resolve any flagged issues (such as incompatible drivers or software).
  4. Make sure your device has enough free disk space (at least 20 GB is advisable for major updates) and that it’s plugged in and online regularly so the update can download and prepare.
  5. If you’re still stuck, you can manually trigger the update using the Windows 11 Installation Assistant or media creation tool, but only do this if you are comfortable with a clean install or in-place upgrade.

If You Manage Business or Enterprise Systems

  • For Windows 11 24H2 in managed environments: Select your next baseline (25H2 or 26H1) and begin pilot deployments immediately. Validate line-of-business applications, group policies, and security configurations. Use tools like Windows Update for Business or Microsoft Intune to control rollout rings and deadlines.
  • For Windows 10 LTSB 2016 devices: Start with a full inventory. Tag each device by business function, criticality, and upgrade feasibility. Some machines may be candidates for a modern Windows 10 LTSC release (2019, 2021, or the new 2024 edition) or for Windows 11 Enterprise LTSC 2024. Others might need full replacement with new hardware.
  • If ESU is the only viable short-term option for LTSB 2016:
  • Ensure the May 2026 servicing stack update (KB5088064) and May 2026 security update (KB5087537) are installed on each device.
  • Obtain the ESU Multiple Activation Key (MAK) from the Microsoft 365 admin center (requires Product Key Reader or VL Administrator role).
  • For Windows 10 IoT Enterprise LTSB 2016, contact your OEM partner for ESU keys.
  • Activate the key on each device using slmgr.vbs /ipk <MAK> and the appropriate year-specific Activation ID from Microsoft’s documentation (Year1: 1b7dbf52-c417-4134-8d68-259906682e61, Year2: deb6f308-6dff-4148-9d6f-eb2bd2fee619, Year3: f2571710-2c24-4677-8fb5-a07d41d3c1aa).
  • Run slmgr.vbs /ato <Activation ID> to complete activation.
  • For offline devices, use the Microsoft Product Activation Portal to obtain a Confirmation ID.
  • Verify the license status with slmgr.vbs /dlv—it should show the ESU program name and status “Licensed.”
  • Plan for the fact that ESU is temporary. A Year1 key does not automatically renew; each year requires a new key and reactivation. Set internal project milestones to migrate off LTSB 2016 before the ESU period ends (up to three years, ending around October 2029 at the latest).

Outlook

Microsoft’s 90-day notice is a tool designed to shake loose both casual users and large enterprises. For the Windows 11 24H2 audience, compliance is straightforward: run Windows Update and move on. But for the hidden infrastructure running on LTSB 2016, October 13, 2026 is not a deadline for a patch cycle—it is the signal to finally retire or rebuild some of the most entrenched devices in the industry. The organizations that act now will treat the ESU program as a measured contingency, not a last-minute scramble. Those that wait will find themselves negotiating expired support, lost certification, and a supply chain that has already moved on.