Understanding Windows 11 monthly updates: Servicing explained

Windows updates help keep devices secure, reliable, and productive. Whether you're an IT admin or a general user, understanding the different types of Windows updates can help you keep devices protected, productive, and continuously improving.

Most individuals and organizations regularly deploy monthly security updates, released on the second Tuesday of each month. Windows also provides optional non-security preview updates, which give IT teams and early adopters an opportunity to validate upcoming fixes before they're included in the next monthly security update.

This guide explains the purpose of each update type, when updates are released, and how they fit into the modern Windows servicing model.

Monthly security updates​

For many of you, the second Tuesday of each month (often referred to as "Patch Tuesday") is a regular part of Windows servicing for client and server endpoints. On this day, we publish monthly security updates for supported versions of Windows.

Monthly security updates are designed to help you maintain security, compliance, and device health. These updates are cumulative. They include security and non-security content introduced in the prior month's security and optional non-security preview updates (see below). In other words, deploying the latest update brings a device up to date with all previously released fixes for that version of Windows. This helps simplify update management and reduce fragmentation across devices.

Note: People tend to use "B release," quality update, security update, monthly cumulative update, and latest cumulative update (LCU) interchangeably.

You can deploy updates through a variety of channels depending on your scenario. General users and some small business environments rely on the built-in Windows Update, allowing Microsoft to manage your updates. Enterprise environments use any combination of Windows Update, Windows Autopatch, Microsoft Intune, Windows Server Update Services (WSUS), Microsoft Configuration Manager, the Microsoft Update Catalog, and/or non-Microsoft tools.

IT admins can also enroll devices in hotpatch updates for a faster time to compliance. Hotpatch updates include security fixes only. They don't include the additional features and enhancements contained in monthly security updates. A quarterly baseline (a monthly security update with restart) is required to bring devices up to date on all the features. After that, the design is that the two subsequent monthly security updates are installed without requiring a restart.

Optional non-security preview updates​

Typically released during the fourth week of the month, optional non-security preview updates provide an opportunity to validate upcoming fixes before they become part of the next monthly security update. Optional non-security preview updates are also cumulative and are only offered for the most recent supported versions[1] of Windows. These updates are intended primarily for early preview of new features before broader rollout, as well as for testing and validation.

New features, like point‑in‑time restore for Windows 11, might initially be released in an optional non-security preview update, then roll out broadly in the following month's security update. Please note that some features roll out gradually, so you might not see them on your devices immediately upon installing an update.

To access optional non-security preview updates on non-IT-managed devices, navigate to Settings > Windows Update > Advanced options > Optional updates. Select from the available updates and select Download and install. Additionally, see how to get Windows updates as soon as they're available for your device. The behavior of IT-managed devices depends on admin controls and policies.

Note: The term "optional non-security preview update" replaces what was formerly referred to as a "C" or "D" release. You might still see lettered shorthand references in IT management tools or documented release information. Inside Windows Update, you'll find them in the format of YYYY-MM Preview Update (KB number) (update build number). Learn more about Simplified Windows Update titles.

Out-of-band update​

In exceptional cases, Microsoft releases an out-of-band (OOB) update outside the normal monthly servicing cadence. These updates are designed to help resolve a known issue or to address an immediate, high-risk security concern. Some of these are optional, while others are recommended as security updates. OOB updates are typically cumulative, meaning they include all previously released fixes for the supported version of Windows in addition to the targeted fix. In enterprise environments, these updates are available for deployment through quality update approval and scheduling in Windows Autopatch, the Microsoft Update Catalog, and other enterprise update management tools.

New features and improvements in Windows 11​

Windows 11 uses multiple delivery mechanisms to bring new features, experiences, and improvements to supported devices throughout the year. New capabilities can reach you through the annual feature update, monthly updates, or Microsoft Store updates, depending on the scenario or applicable IT controls. This enables us to deliver enhancements when they're ready while maintaining quality and reliability.

In some cases, features become available to devices gradually over time, helping validate quality and compatibility before broader rollout. Aside from using optional non-security preview updates to release new capabilities before enabling them more broadly, Microsoft also uses Controlled Feature Rollout (CFR) technology. Capabilities released via CFR technology are typically disabled by default for organizations. If your organization needs greater control over when certain features become available, you can use commercial management controls.

Recommendations​

Keeping devices up to date is critical for security. We recommend that organizations install the latest security updates as soon as they become available.

We also encourage you to take advantage of optional non-security preview updates to internally validate features and fixes ahead of the following month's security update. For early access to the latest Windows features and to give feedback, join the Windows Insider Program.

To help manage updates across your organization, bookmark these:

• Update history and release notes: Windows 11, versions 25H2 and 24H2
• Windows release health (also available in the Microsoft 365 admin center)
• Additional tips and resources in Your Windows release information toolbox
• The updated reference onthe Update release cycle for Windows clients

Whether you're updating your personal device or deploying updates across your organization, understanding the Windows servicing model can help you make informed decisions. Now you can manage updates better, prepare for new features with confidence, and keep devices protected and productive throughout the year.

[1] As of July 9, 2026, "most recent supported versions" refers to Windows 11, versions 26H1, 25H2, and 24H2.