In-Place Upgrade from Server 2016 to 2025: What's Possible Since the N-4 Path

In brief: Since Windows Server 2025, Microsoft has allowed non-clustered systems to skip up to four versions in one step. The direct path from Server 2016 to Server 2025 via installation media is documented and supported. The detour via 2019 or 2022 is no longer necessary.

What has changed

Until Windows Server 2022, the rule was: non-clustered systems could skip two versions at once. So, from 2016, you could go to 2022, but not to 2025. If you wanted to go further, you needed two passes, two maintenance windows, and two risks.

With Server 2025, Microsoft has extended this to four versions. Server 2016, 2019, and 2022 are all listed as supported sources for a direct upgrade to 2025. For many environments, this halves the effort.

Important: The direct path applies to media-based upgrades via ISO. Via Windows Update, the path to 2025 is currently only intended from Server 2019 and 2022.

Where the path does not apply

Failover Clusters. The Cluster OS Rolling Upgrade still applies there, and only one version step at a time is planned. So, moving from 2016 to 2025 in a cluster requires a multi-stage approach.

Domain Controllers. Technically, an in-place upgrade is possible, but not recommended. The clean way is a new DC, replication, transfer FSMO roles, demote the old DC.

Servers with SQL Server 2016. The SQL service must first be upgraded to a compatible version, then the operating system. SQL Server 2016 has been out of support since July 14, 2026.

The preparation no one should skip

Backup and rollback. A full backup is the minimum. On a hypervisor, also a snapshot. And a documented, tested rollback path, not just the intention to be able to revert in an emergency.

Vendor releases. Ask each software vendor individually if Server 2025 is released. In writing. This is the step that can derail projects, and it takes weeks with some providers. Assuming compatibility is a direct path to failure.

Drivers and firmware. Storage controllers, network cards, firmware up to date. Older hardware without current drivers for 2025 is a reason to go to Server 2022 instead.

NIC Teaming. Dissolve before the upgrade, then set up again. This is the most common avoidable pitfall.

Edition and language. Standard remains Standard, Datacenter remains Datacenter. Changing the language version during an upgrade does not work.

License. You need a valid license for the target version, not an evaluation medium. And you need CALs of the target version for every access. Details on this: Why your old Server CALs become worthless when upgrading

What practice says

Success rates in field reports vary widely, and there's a clear reason for that. A German service provider reports approximately 250 accompanied terminal server upgrades with exactly one failure. Other sources cite rates around 60 percent for mixed inventories.

The difference lies in the state of the source machine. A cleanly maintained application server with current drivers and documented configuration will go through. An installation that has grown over ten years with legacy drivers, half-uninstalled agents, and three generations of antivirus remnants is another case. If you don't know the state, you should plan a fresh installation instead of an in-place upgrade.

2022 or 2025 as target?

Server 2022 is the pragmatic choice if your industry software is not released for 2025, the hardware is older, or the budget is tight. Security updates until October 14, 2031. However, mainstream support ends on October 13, 2026, after which there will only be security patches.

Server 2025 is the choice if the machine is to run beyond 2031 or if you want hotpatching. Support until November 14, 2034.

You can find the servers themselves under Windows Server, further basics in the Server Guide.

Related: Windows Server 2016 End of Support: Cost comparison of the four paths