.NET 8 and .NET 9 Support Ends This November, Microsoft Warns

Microsoft said support for .NET 8 and .NET 9 will end on November 10, 2026.

Existing apps will keep running, but Microsoft will stop delivering fixes and security patches for those versions.

The company is urging developers to upgrade to supported releases, especially .NET 10.

Once support ends, apps staying on .NET 8 or .NET 9 face higher maintenance and security risk.