Windows Server 2019 to 2025 Upgrade Guide
Windows Server 2019 is getting older, and Windows Server 2025 supports a direct in-place upgrade path from it, no need to jump through Windows Server 2022 first. Here’s exactly what you need before you start, how the upgrade works, and where it can go wrong.
Can You Upgrade Directly from Windows Server 2019 to 2025?
Yes. Windows Server 2019 to Windows Server 2025 is a supported in-place upgrade path for nonclustered systems, available both through installation media and through Windows Update directly. Since mid-April 2026, Microsoft has allowed this upgrade through Windows Update with no ISO or DVD required at all.
An in-place upgrade keeps your installed applications, settings, and server roles intact. Only the operating system version changes underneath them.
Prerequisites Before You Upgrade
Check these before you start, missing any one of them will block the upgrade:
- Cumulative updates: Your Windows Server 2019 installation needs the March 2026 cumulative update installed at minimum. Specifically, update KB5078752 or later must already be applied.
- Disk space: At least 30 GB of free space on the drive where Windows is installed (typically C:).
- New product key: If you’re running a Retail or OEM licensed copy of Windows Server 2019, you’ll need to purchase a genuine Windows Server 2025 product key before the upgrade completes. Volume-licensed environments handle this differently through their existing agreement.
In-Place Upgrade vs Clean Install
In-place upgrade is the faster, lower-disruption option, and it’s what most standalone application servers, file servers, and print servers should use.
Don’t use in-place upgrade if your server runs Active Directory Domain Services (AD DS). It’s technically possible, but it won’t give you the AD performance and feature improvements built into Windows Server 2025. For domain controllers, the recommended path is a clean install of Windows Server 2025 to stand up new domain controllers, then demote the old Windows Server 2019 domain controllers once replication is confirmed.
If you’re running SQL Server, Exchange, or other server applications alongside Windows Server 2019, check that application’s own OS-support matrix before upgrading, application compatibility is separate from Windows Server’s own upgrade support.
Step-by-Step Upgrade Process
1. Confirm your server meets the cumulative update prerequisite (KB5078752 or later).
2. Back up the server fully before doing anything else. An in-place upgrade is not the moment to skip this.
3. Confirm you have your new Windows Server 2025 product key ready if you’re on Retail or OEM licensing.
4. On the server itself, check for updates through Windows Update, Windows Server 2025 will appear as an available feature update once your prerequisites are met.
5. Start the upgrade and enter your new product key when prompted.
6. Let the upgrade complete without interrupting it, this can take a while depending on server size and installed roles.
7. After reboot, verify installed roles and applications are functioning correctly before considering the upgrade complete.
If you’d rather use installation media instead of Windows Update, the same prerequisites apply, you’ll just run setup.exe from the mounted Windows Server 2025 ISO instead.
What’s New in Windows Server 2025
Beyond the Standard Edition capacity increases, Windows Server 2025 brings improvements across storage, networking, and security that make the upgrade worthwhile for most environments. If you’re also deciding between 2025 and 2022 for a fresh deployment rather than an upgrade, see our Windows Server 2025 vs 2022 comparison.
Before upgrading, confirm your hardware meets the Windows Server 2025 system requirements, older hardware that ran 2019 comfortably may need a closer look before taking on 2025.
Buy Your Windows Server 2025 License
Since a Retail or OEM upgrade requires a new product key, get yours from a genuine, perpetual license, no subscription:
Not sure which edition or core count fits your environment? See our Windows Server 2025 pricing guide or contact us directly and we’ll help you size it before you buy.
If you’re still running Windows Server 2012 or 2016 and trying to decide where to land, our 2012 vs 2016 vs 2019 comparison covers the older upgrade paths too.
Frequently Asked Questions
Can I upgrade directly from Windows Server 2012 or 2016 to 2025?
No, Microsoft’s supported in-place upgrade path covers Windows Server 2019 and 2022 to 2025. If you’re on 2012 or 2016, you’ll need a clean install of Windows Server 2025 instead of an in-place upgrade.
Do I need a new product key if I have Software Assurance
Volume-licensed customers with active Software Assurance typically have upgrade rights included, check your existing agreement rather than purchasing a new retail key.
Will my installed applications survive the upgrade?
Yes, in-place upgrade preserves installed applications, roles, and settings. Always confirm your specific application vendor supports running on Windows Server 2025 before upgrading a production system.
How long does the upgrade take?
Yes, in-place upgrade preserves installed applications, roles, and settings. Always confirm your specific application vendor supports running on Windows Server 2025 before upgrading a production system.
How long does the upgrade take?
This varies by server size, installed roles, and hardware, but plan for it to take longer than a typical Windows Update patch cycle. Schedule it during a maintenance window, not during business hours.
What happens if the upgrade fails partway through?
This is exactly why backing up beforehand matters. A failed in-place upgrade can leave a server in an unusable state, and a recent backup is the fastest way back to a working system.
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