Windows Server and Stack HCI Timeline

Microsoft’s server OS offerings are supported on three different cadences that reflect their intended use cases. Although the Windows Server LTSC supports the broadest range of scenarios and offers the most stability, the Windows Server Annual Channel for Containers and Azure Stack HCI have deeper support for specific scenarios and receive new capabilities before LTSC versions. (The former Semi-Annual Channel [SAC] is no longer offered, and all SAC versions have left support.)

Windows Server 2022, the latest Long-Term Servicing Channel (LTSC) version of Windows Server, was released in Aug. 2021. Windows Server 2025, the next LTSC version, was announced by Microsoft in Jan. 2024 with general availability planned for the second half of 2024.

LTSC versions of Windows Server provide five years of Mainstream support and five years of Extended support. Windows Server 2022, 2019, and 2016 offer Desktop Experience (“Full”) and Server Core installation modes, with Server Core as the default installation mode. Windows Server 2012 and 2012 R2 left Extended support in Oct. 2023 and are supported only via Extended Security Updates (ESUs) until at least Oct. 2026. ESUs are a paid program for on-premises workloads offering security updates for up to three years after the conclusion of Extended support. For workloads hosted in Azure VMs or on Azure Stack HCI on-premises, ESUs are provided at no additional cost.