.NET is a mature, cross-platform framework, and ASP.NET Core is Microsoft's open-source web framework for it, designed for large-scale applications. The date that matters now is 10 November 2026: support for both .NET 8 and .NET 9 ends then, and .NET 10, a long-term support release, is supported until 14 November 2028. If your enterprise system runs on .NET 8 or 9, plan the move to .NET 10 this quarter; if you are starting a new build, start on .NET 10 and hire for skills in the framework, not only the language.
Key takeaways
- Microsoft's support page (updated 8 September 2026) lists .NET 8 (LTS) and .NET 9 (STS) as ending support on 10 November 2026, and .NET 10 (LTS) as supported until 14 November 2028.
- LTS releases get 3 years of free support and patches, STS releases 2 years; the quality is the same, and a new major version ships every November.
- To stay supported you must install the latest patch for your version.
- Microsoft describes ASP.NET Core as "cross-platform, high-performance, open-source" and "built for large-scale app development".
- .NET 11 is at release candidate stage; Microsoft lists no general availability or end-of-support date for the final release on that page.
Which .NET versions are supported?
| Version | Type | Latest patch (8 Sep 2026) | Phase | End of support |
|---|---|---|---|---|
| .NET 8 | LTS | 8.0.31 | Maintenance | 10 November 2026 |
| .NET 9 | STS | 9.0.20 | Maintenance | 10 November 2026 |
| .NET 10 | LTS | 10.0.12 | Active | 14 November 2028 |
| .NET 11 | RC1 (go-live) | Go-live | RC1 only; final dates not listed |
During active support you get fixes and security updates; the last six months of a release are maintenance, with security fixes only. After end of life there are no more fixes. Older versions such as .NET Core 3.1 and .NET 5 are long out of support, so any system still on them is a priority.
What does ASP.NET Core offer enterprise teams?
Microsoft's overview lists:
- A lightweight, modular request pipeline and the Kestrel server.
- Integrated dependency injection and environment-based configuration.
- Rich logging, tracing and runtime metrics.
- Minimal APIs, gRPC for high-performance services and SignalR for real-time features.
- Blazor, for interactive web interfaces in C# without JavaScript, and integration with front-end frameworks such as Angular, React and Vue.
- Built-in support for authentication, authorization and data protection.
- Support for unit and integration testing.
Microsoft says it is used at large scale by services including Bing, Xbox, Microsoft 365 and Azure. As with any vendor claim, check it against your own workload by testing.
When is .NET a good fit?
- Organisations already on Microsoft tools, such as Windows servers, SQL Server or Azure.
- Large business systems with many integrations, strict security needs and long lives.
- Teams with C# skills.
- Cloud-hosted services of any size; ASP.NET Core runs cross-platform and is described as cloud-ready.
For other choices, see Node.js frameworks in 2026 and Angular in 2026, which pairs well with a .NET back end. Our .NET development page describes our work.
How should you plan an upgrade?
- Inventory every application and its .NET version.
- Prioritise anything on .NET 8 or 9 (support ends 10 November 2026) and anything older.
- Read the breaking changes for each step and check your libraries and hosting support the target.
- Upgrade in a branch, run automated tests and fix what breaks.
- Deploy gradually, then keep a yearly cadence: a new major version ships every November.
- Install every patch. Microsoft's support requires the latest patch for your version.
What should you look for when hiring .NET developers?
Ask about skills that matter in enterprise work, not only C# syntax:
- Experience upgrading applications across versions and handling breaking changes.
- API design, authentication and authorization, and data protection.
- Testing habits: unit, integration and automated checks.
- Cloud deployment, logging and monitoring.
- How they use AI coding assistants, and how they review the output; our own policy is that people review all generated code.
Read How to hire an app development company in 2026 for a general checklist.
FAQ
When does .NET 8 end support?
On 10 November 2026, according to Microsoft's support policy page. .NET 9 ends on the same date, and .NET 10 is supported until 14 November 2028.
What is the difference between LTS and STS?
LTS releases are supported for 3 years and STS releases for 2 years. Microsoft says the quality is the same; only the length of support differs.
Is ASP.NET Core only for Windows?
No. Microsoft describes it as cross-platform.
Should we wait for .NET 11?
.NET 11 is at release candidate stage. For production, use a supported release such as .NET 10 and plan to move on a schedule.
Does .NET work with Angular or React front ends?
Yes. Microsoft's ASP.NET Core overview lists integration with Angular, React and Vue.
Sources
- Microsoft, ".NET and .NET Core Support Policy": https://dotnet.microsoft.com/en-us/platform/support/policy/dotnet-core
- Microsoft Learn, "Overview of ASP.NET Core": https://learn.microsoft.com/en-us/aspnet/core/introduction-to-aspnet-core
