Microsoft is changing how it delivers Windows updates: 4 things you need to know

Microsoft is about to make a significant change in the way it delivers security updates and new features for Windows 11. You can still expect to see a single update package on the second Tuesday of each month (aka Patch Tuesday). But instead of being delivered as a single update file that grows larger every month, Microsoft is introducing what it calls "checkpoint cumulative updates".

In a post on the Windows IT Pro Blog, Microsoft's Maliha Qureshi explains that the goal of the new update concept is to make the monthly routine "smaller, faster, and more sustainable", especially for administrators in large organizations.

Also: When Windows 10 support runs out, you have 5 options but only 2 are worth considering

Under the new delivery system, the post explains, Microsoft might periodically release cumulative updates as checkpoints. Subsequent updates would then consist of smaller update package files that contain "incremental binary differentials against the version of binaries in the last checkpoint".

Over its supported lifecycle, a Windows release might have several of these checkpoints. Starting with Windows 11, version 24H2, Microsoft says, the servicing stack (the code that manages the process of downloading and installing Windows updates) will be able to "merge all the checkpoints and only download and install content that's missing on the device."

If you think that sounds confusing, you're not alone. Fortunately, there's time to figure out exactly how it's going to work. The new system won't be publicly available until the end of the year, as part of Windows 11, version 24H2. The first release in this new format is going out as part of this week's Windows Insider Dev Channel release.

If you own one or more Windows PCs, here are four things you need to know about the new update format.

1. Checkpoint updates should be smaller and easier to manage

Today, monthly Windows updates are cumulative. The update package delivered on Patch Tuesday each month contains all the fixes that were in the previous month's cumulative update, along with whatever new features and fixes Microsoft is delivering that month.

That system has the advantage that you only ever need to install the latest cumulative update, even on a system that's been out of service for months. But that design also means that, inevitably, those update packages get bigger and bigger every month. And now that each new version of Windows 11 is supported for two full years, those packages can get pretty large.

Also: 7 ways to make Windows 11 less annoying

For example, the July 2023 cumulative update package for x64 systems running Windows 11 version 22H2 was 302MB. Over the course of the next year, each monthly update added some bulk, and by the end of the year the December 2023 was more than double that size, at 622.5MB. The July 2024 update has grown to 728.7MB in size.

Each Windows PC has to download and install each of those successively larger updates, a time-consuming process. Over the course of the first seven months of 2024, every Windows 11 PC owner has had to deal with more than 4.8GB of updates. Multiply that by a billion or more PCs and that's a lot of bandwidth!

Using checkpoint updates, by contrast, you could have installed a 622MB package in December that brought the system up to date. Update packages for succeeding months would be less than 100MB each, on average, cutting the total download burden by 80% or more.

2. The new update packages are only available to beta testers today

As I mentioned earlier, Microsoft is rolling out the new servicing stack as part of the Windows 11, version 24H2 release. If you've enrolled a PC in the Windows Insider Dev Channel, you can see the results in Preview Build 26120.1252.

Also: Windows 11: Do these six things right away after you finish setup

These changes won't be available to members of the Windows Insider Program who are enrolled in the Beta or Release Preview channels, and most members of the general public won't see the 24H2 release until sometime in 2025.

3. You probably won't notice the change

If you manage the PCs in your home and business using Windows Update, you probably won't notice any change even after it takes effect in Windows 11, version 24H2. Unless you've changed the default settings, Windows will install the Patch Tuesday updates just as it normally does. It's possible that those monthly updates will go faster, but even if you're paying close attention, you're not likely to notice until the first checkpoint update hits the Windows Update servers sometime in mid- to late 2025.

The story's a little different for IT pros and network administrators who manage updates for a large number of Windows PCs over a corporate network. Those poor souls will need to keep track of checkpoints and subsequent updates and make sure they're delivered properly using whatever update tool they've deployed. Microsoft's management products should do a good job of sequencing those updates, but admins have a right to be skeptical and to test thoroughly before widely deploying the 24H2 release.

4. This won't affect Windows 10 users at all

For those who've decided to stick with Windows 10, checkpoint updates are a non-issue. As long as you've installed the final supported release of Windows 10, version 22H2, you'll continue getting cumulative updates in the traditional format until the end-of-support date in October 2025. You'll need to continue installing one of those large cumulative updates (the latest x64 package is roughly 650MB in size) every month.

Also: 11 Windows touchpad tricks to help you work faster and smarter

After that date, you can choose your Windows 10 update strategy, but no matter which option you select, it won't involve checkpoints.