Patch Tuesday is the informal name for Microsoft's monthly security update. It is published on the second Tuesday of each month, typically at 10:00 AM Pacific Time. The update is cumulative, so it carries new security fixes plus earlier ones. Operations teams plan their month around it.
What Patch Tuesday actually is
Microsoft's own documentation calls the release the monthly security update. The same page lists the nicknames you will see in tickets and chat: Patch Tuesday, Update Tuesday, B week releases (the second week of the month), quality update, security update and latest cumulative update (LCU).
Most organizations treat the monthly security update as mandatory. It reaches devices through Windows Update, Windows Server Update Services (WSUS) and the Microsoft Update Catalog. Larger shops usually run it through a management tool on top of those channels.
The next dates
The second Tuesday is easy to compute, but it helps to put the dates in a shared calendar once.
| Month | Second Tuesday |
|---|---|
| November 2026 | 10 November |
| December 2026 | 8 December |
| January 2027 | 12 January |
| February 2027 | 9 February |
If Microsoft changes a date, its release notes win over any calendar you built from the rule.
The other updates around it
Patch Tuesday is one of several release types in the same cycle.
| Release type | When | Purpose |
|---|---|---|
| Monthly security update | Second Tuesday | Security and non-security fixes, cumulative |
| Optional non-security preview | Fourth week | Early validation of next month's content |
| Out-of-band update | As needed | A recent issue or vulnerability that cannot wait |
| Annual feature update | Once a year, second half | New features, changes the Windows version |
The preview update matters to ops because it lets you test content a few weeks before it ships in the security update. Our post on out-of-band updates covers the unscheduled case.
A weekly routine that fits the cycle
This is a suggested routine, not a Microsoft requirement. Adjust the days to your change windows.
- Tuesday: read the release notes and the vulnerability list. Flag anything marked as exploited, and anything on your internet-facing systems.
- Wednesday: push to a pilot ring of a few devices and servers you can afford to break.
- Thursday and Friday: watch for failed installs and application complaints.
- The following week: roll out in rings, internet-facing and high-value systems first.
- End of week two: report what is installed, what is deferred and why.
Keep a short exception list with an owner and a date for every deferral. An exception with no date turns into permanent risk.
Try it yourself
Click through it at your own pace, or open it full screen.
Click into a finding and look at how severity, fix availability and ownership sit together, which is the view you want on the Wednesday after a big release.
Safeguard does SBOM and dependency scanning, reachability analysis and policy gates, which helps you see what a release touches in your own code. You can try a free scan.
Quick check
Is Patch Tuesday always on the second Tuesday?
Microsoft's documentation says the monthly security update is published on the second Tuesday of each month. Out-of-band updates are the exception and arrive when an issue cannot wait.
Do I have to install the optional preview update?
No. It is optional and typically arrives in the fourth week. Admins use it for early validation before the next monthly security update.
Sources
- Microsoft Learn, Update release cycle for Windows clients
Last reviewed: 19 October 2026.
