Transport Layer Security (TLS) 1.3 is the latest version of the TLS protocol, offering significant improvements in performance, security, and privacy compared to its predecessors. It reduces handshake latency, removes obsolete cryptographic algorithms, and enhances forward secrecy, making it the preferred protocol for modern secure communications.

Despite these advancements, support for TLS 1.3 in Microsoft Windows is limited to newer operating systems. Native and official support is fully available only in Windows 11 and Windows Server 2022, where it is enabled by default and integrated into the Schannel security provider.

In contrast, Windows 10 (version 1903 and later) and Windows Server 2019 include some internal TLS 1.3 plumbing, but Microsoft does not officially support or enable TLS 1.3 in these versions. As a result, legacy systems continue to rely on TLS 1.2 or earlier, requiring careful planning when adopting TLS 1.3 in Windows-based environments.

TLS 1.3 support in Windows versions

Details

• Schannel (Microsoft's TLS stack) only fully supports TLS 1.3 on Windows 11 and Server 2022+.

• Windows Server 2019 and Windows 10 have the necessary plumbing (e.g., registry keys and internal support), but Microsoft has not officially enabled TLS 1.3.

• Enabling it manually (via registry) may not work reliably, especially for server-side services like IIS.

• TLS 1.3 is only officially supported in Windows Server 2022 and Windows 11.
  On Server 2019 and Windows 10, even though you can configure registry keys, it won't actually work through Schannel.

Matrix of Windows versus TLS 1.3 support