.NET 8 and 9 support dropping Time to upgrade
Imagine arriving at your desk to find that your core production runtime goes end-of-life on the same day as your last stable minor release. That is the reality facing teams running modern .NET workloads right now. We have been watching Microsoft’s release cadences closely, and the latest official announcement lays out a synchronized deprecation schedule that might catch a few engineering teams off guard. Security patches are stopping, compliance requirements are hanging in the balance, and the migration path to .NET 10 needs to be prioritized on your immediate roadmap.
News Summary
Microsoft Senior Program Manager Rahul Bhandari announced that both .NET 8 and .NET 9 will officially reach their End of Support (EOS) on November 10, 2026. After this date, Microsoft will stop providing servicing updates, critical security fixes, and official technical assistance for both versions.
The simultaneous drop results from a fundamental structural shift in Microsoft's Support Policy. .NET 8 launched in November 2023 as a Long Term Support (LTS) release, granting it a standard 36-month lifespan. Conversely, .NET 9 launched in November 2024 as a Standard Term Support (STS) release. Microsoft recently adjusted its STS lifecycle policy to extend support to 24 months instead of the older 18-month window.
Because of this specific policy recalibration, the timelines for both versions intersect perfectly on November 10, 2026. This date also lands directly on a standard Microsoft Patch Tuesday cycle. While both runtimes could receive one final security patch on that specific day to address outstanding critical flaws, all engineering support terminates immediately afterward.
The deprecation will directly affect local development environments. Future servicing updates for Visual Studio 2022 will explicitly flag .NET 8 and .NET 9 internal components as out of support. While active local instances won't instantly break, Microsoft will provide automated options within the Visual Studio Installer to completely purge the legacy, unsupported runtimes from your developer machines.
Developer Impact
What this means for developers is an immediate requirement to audit infrastructure. If you are running web apps, background workers, or cloud-native APIs on .NET 8 or 9, they will continue executing after November 10, 2026. However, you are operating on borrowed time.
Running unsupported runtimes in production introduces unpatched security vulnerabilities and instantly breaks SOC2 or PCI-DSS compliance frameworks. If you build client software or ship SaaS platforms on these versions, you must immediately coordinate with your dependencies and upgrade development environments to target .NET 10.
Our Analysis
Our take on this strategy is highly positive, despite the compressed migration timeline it forces on enterprise developers. Syncing the end-of-life dates for an LTS and an STS release cleans up the fragmentation that frequently plagues the .NET ecosystem. It forces engineering teams to cut out the intermediate steps and move directly to a stable target.
We predict this dual deprecation will trigger a massive surge in .NET 10 adoption over the next two quarters. Teams that usually skip odd-numbered STS releases like .NET 9 to camp out on LTS versions will no longer have the luxury of waiting. They must jump directly from .NET 8 to .NET 10.
When contrasted with older migration cycles-like the messy transition periods seen during the old .NET Framework to .NET Core era-the modern upgrade path is significantly more streamlined. Microsoft has successfully regularized its release cadence. However, the catch is that the support windows are much tighter now.
You can no longer leave a modern .NET application running unattended for five years without expecting a runtime deprecation. If you want to maintain long-term architectural stability with minimal maintenance overhead, targeting .NET 10 is your best path forward, as its LTS status guarantees security patches through November 2028.
| .NET Version | Release Type | Release Date | End of Support Date | Support Duration |
| .NET 8 | LTS (Long Term Support) | Nov 14, 2023 | Nov 10, 2026 | 36 Months |
| .NET 9 | STS (Standard Term Support) | Nov 12, 2024 | Nov 10, 2026 | 24 Months |
| .NET 10 | LTS (Long Term Support) | Nov 11, 2025 | Nov 2028 | 36 Months |
To migrate your service, you need to update your project file (.csproj) to retarget the modern runtime framework. Here is a clean, minimal example of how your configuration file should look:
<Project Sdk="Microsoft.NET.Sdk.Web">
<PropertyGroup>
<!-- Change from net8.0 or net9.0 to net10.0 to migrate your runtime -->
<TargetFramework>net10.0</TargetFramework>
<Nullable>enable</Nullable>
<ImplicitUsings>enable</ImplicitUsings>
</PropertyGroup>
</Project>FAQs
Q: Will my existing .NET 8 or .NET 9 apps stop running on November 10, 2026?
A: No, your compiled binaries and containerized applications will continue to execute normally. However, Microsoft will no longer issue any security updates, patches, or technical assistance if things break.
Q: Can I still use Visual Studio 2022 to build .NET 8 apps after the deadline?
A: Yes, your existing development setups won't be modified automatically. However, future Visual Studio updates will mark those components as out of support and offer automated tools to remove them.
Q: Why are .NET 8 and .NET 9 ending support on the exact same day?
A: Microsoft extended the lifecycle of Standard Term Support (STS) releases to 24 months. Because .NET 9 launched a year after .NET 8, its new 2-year window ends exactly when .NET 8’s 3-year LTS window closes.
Q: How do I upgrade my application to .NET 10?
A: You need to change the TargetFramework property in your project file to net10.0. You will also need to update your CI/CD pipelines, build agents, and hosting environments to support the .NET 10 SDK.
Our Take
The synchronized end-of-support deadline for .NET 8 and 9 clarifies Microsoft’s long-term infrastructure playbook. Modern software engineering demands active lifecycle management, and camping on legacy runtimes is a liability. Do not wait for the November deadline to scramble a migration plan together; update your project files and start running your integration test suites against .NET 10 today. We will be tracking the ecosystem's migration trends and breaking changes closely as the deadline approaches.
