Short answer: Microsoft support for .NET 8 (including ASP.NET Core 8 and EF Core 8) ends on 10 November 2026. After that date, .NET 8 receives no more security patches or bug fixes. Your applications will keep running, but every new vulnerability will stay unpatched. The recommended path is to upgrade to .NET 10, the current long-term support (LTS) release, supported until November 2028. For most .NET 8 applications this is a manageable upgrade, not a rewrite.
.NET support timeline at a glance
| Version | Release type | End of support | Status |
|---|---|---|---|
| .NET 6 | LTS | November 2024 | Unsupported |
| .NET 7 | STS | May 2024 | Unsupported |
| .NET 8 | LTS | 10 November 2026 | Ends next month |
| .NET 9 | STS | 10 November 2026 | Ends next month |
| .NET 10 | LTS | November 2028 | Recommended |
Microsoft extended support for standard-term (STS) releases to 24 months, so .NET 9 reaches end of support on the same day as .NET 8. See the official Microsoft announcement: .NET 8 and .NET 9 end of support.
What “end of support” really means
- No security patches: new vulnerabilities in the runtime or ASP.NET Core will not be fixed for .NET 8.
- No bug fixes or technical support from Microsoft.
- Your app keeps running: nothing switches off on 10 November, but risk grows every month.
- Compliance risk: security audits, cyber insurance and frameworks such as SOC 2, ISO 27001, HIPAA or PCI DSS usually expect supported software.
- Library support fades: NuGet packages and cloud SDKs gradually drop older versions.
Who needs to act
- Any web app, API, background service or function running on .NET 8 or .NET 9.
- Teams using Docker images based on .NET 8 or 9 tags.
- Azure App Service, Azure Functions or AWS workloads on the .NET 8 or 9 runtime.
- Desktop apps (WPF, WinForms) built on .NET 8 or 9.
Still on .NET Framework 4.x? That is a different situation. .NET Framework 4.8 continues to receive security fixes as part of Windows, but it gets no new features, and technologies such as ASP.NET WebForms cannot move to modern .NET without a migration. See our WebForms to ASP.NET Core migration guide.
Your options
| Option | What it means | When it fits |
|---|---|---|
| Upgrade to .NET 10 (recommended) | Move to the current LTS release, supported until November 2028 | Almost every active application |
| Stay on .NET 8 temporarily | Accept unpatched risk for a short, planned period | Only with a firm upgrade date and extra security monitoring |
| Retire or replace the app | Decommission, or rebuild on a modern platform | Apps that are no longer used or need major redesign anyway |
How to upgrade from .NET 8 to .NET 10: step by step
- Inventory: list every app, service, function and container on .NET 8 or 9, with owners and hosting.
- Check dependencies: confirm your NuGet packages, ORMs, authentication libraries and third-party SDKs support .NET 10.
- Review breaking changes: read Microsoft’s breaking-change notes for .NET 9 and .NET 10, especially ASP.NET Core and EF Core.
- Update the target framework: change
net8.0tonet10.0, update the SDK in global.json and update packages such as EF Core. - Update hosting: switch Docker base images, Azure App Service or Functions runtime stacks and CI/CD build agents to .NET 10.
- Test thoroughly: run unit, integration and regression tests, plus a performance and security check.
- Deploy in stages: release to a staging environment first, then production, with a rollback plan.
How long and how much will it take?
Moving from .NET 8 to .NET 10 is usually far smaller than migrating from .NET Framework. A single, well-tested application can often be upgraded in days to a few weeks. Larger estates with many services, older libraries or limited test coverage take longer. The main cost drivers are the number of applications, outdated dependencies, missing automated tests and hosting changes. Our ASP.NET development cost guide explains typical rates.
Benefits of moving to .NET 10
- Security patches and support until November 2028.
- Performance improvements across the runtime, ASP.NET Core and EF Core.
- Latest C# language features and tooling.
- Continued support from libraries, cloud platforms and hosting providers.
- A cleaner base for adding new features and AI capabilities.
Common upgrade pitfalls
- Leaving the upgrade until the last week, with no time to test.
- Forgetting background services, Azure Functions or containers.
- Old NuGet packages with no .NET 10 version.
- Not updating CI/CD pipelines and build servers.
- Skipping performance and security testing after the upgrade.
Get help with your .NET upgrade
Three Circle is an ASP.NET development company based in Texas and the UK. We upgrade .NET 8 and .NET 9 applications to .NET 10, migrate legacy .NET Framework and WebForms systems, and provide ongoing support. See our .NET migration services, software maintenance services or request a free upgrade assessment.
Get a Free .NET Upgrade Assessment
Frequently asked questions
.NET 8 reaches end of support on 10 November 2026. After that, Microsoft no longer provides security updates or bug fixes for it.
No. It will keep running, but new security vulnerabilities will not be patched, which increases risk over time.
Upgrade to .NET 10. It is the current long-term support release, while .NET 9 reaches end of support on the same day as .NET 8.
For most applications it is a manageable upgrade: update the target framework, packages and hosting, then test. Effort depends on dependencies and test coverage.
No. .NET Framework 4.8 follows a different support policy tied to Windows, but it receives no new features, so modern .NET is still recommended for active applications.
