Windows Server 2025 Editions & Licensing | Buyers Guide

Which Windows Server 2025 edition should you choose?

Windows Server 2025 is Microsoft's latest server operating system. It supports deployments ranging from small offices to large datacentres and is available in Essentials, Standard and Datacenter editions.

Essentials Edition

For small businesses with up to 25 users or 50 devices. Essentials supports one CPU with a maximum of 10 cores and does not require Windows Server CALs.

Single CPU licence
No CALs required
Up to 25 users or 50 devices

Standard Edition

For physical or minimally virtualised environments. A licensed server can run Windows Server on the physical hardware and in up to two virtual machines, with no limit on Linux VMs.

Licensed per CPU core
Windows Server CALs required
Up to two Windows Server VMs

Datacenter Edition

For highly virtualised datacentres and cloud environments. Datacenter supports unlimited Windows Server VMs and advanced software-defined storage and networking.

Licensed per CPU core
Windows Server CALs required
Unlimited Windows Server VMs

Edition	Essentials	Standard	Datacenter
Price	LOWERHIGHER

Windows Server 2025 Features

Feature comparison of Windows Server 2025 Essentials, Standard and Datacenter editions
Feature	Essentials Edition	Standard Edition	Datacenter Edition
User Limit Concurrent users that can access the server.	25 (or 50 devices)	Unlimited	Unlimited
Maximum RAM Total supported system memory.	64GB	4 PB	4 PB
Maximum CPUs Total supported processor sockets.	1	64	64
Maximum CPU Cores Total supported physical cores.	10	Unlimited	Unlimited
Virtual Machines (VMs) Hyper-V instances per licence.	1	2	Unlimited
Windows Admin Centre	✔	✔	✔
System Insights	✔	✔	✔
Network Controller	✔	✔	✔
Azure DNS Server	✔	✔	✔
Device Health Attestation	✖	✔	✔
Hybrid Integration	✖	✔	✔
Server Containers	✖	Windows: Unlimited Hyper-V: 2	Windows: Unlimited Hyper-V: Unlimited
Software Defined Networking	✖	✔	✔
Storage Replica	✖	Single 2TB volume	Unlimited
Shielded VMs	✖	✖	✔
Hyper-Converged Infrastructure	✖	✖	✔

✔ = Included | ✖ = Not included

Windows Server 2025 CPU Core Licensing

Windows Server 2025 Standard and Datacenter editions are licensed per CPU core. The standard installations are licensed for 16 or 24 CPU cores, so if your server has more cores than this you will need to buy additional CPU licence packs.

These are available in multiples such as 2, 4 and 16 additional cores. Additional CPU licences are available as POS (point of sale) when you first commission a server, and APOS (after point of sale) when you upgrade the CPU(s) and need more CPU licences.

Here are some sample scenarios:

Your server has 40 CPU cores - buy the base 24-core licence plus an additional 16-core CPU licence.

Your server has 128 CPU cores - buy the base 24-core licence, plus five additional 24-core CPU licences and two 4-core CPU licences.

Windows Server 2025 User Licensing

Windows Server 2025 Standard and Datacenter editions support an unlimited number of users, but each user requires an individual User CAL or a Device CAL (Client Access License). Which CAL you should choose depends on how you intend to use your Windows Server 2025 software.

User CAL

Purchase a CAL for every user who accesses the server, regardless of the number of devices they use. User CALs suit employees who need roaming access using multiple or unknown devices, or organisations with more devices than users.

Device CAL

Purchase a CAL for every device that accesses the server, regardless of the number of users. Device CALs suit organisations where workers share devices, for example on different work shifts.

Upgrade to Windows Server 2025

Windows Server 2025 advances security, performance, cloud integration and containerisation beyond older releases. The table compares key capabilities and direct upgrade support.

Feature and direct upgrade comparison for Windows Server 2008R2 through Windows Server 2025
Feature	2008R2	2012R2	2016	2019	2022	2025
Azure Hybrid Integration	✖	✖	✖	✔	✔	✔
Storage Spaces Direct	✖	✖	✖	✔	✔	✔
Storage Migration Services	✖	✖	✖	✔	✔	✔
System Insights	✖	✖	✖	✔	✔	✔
VM Protection	✖	✖	✔	✔	✔	✔
Data Deduplication	✖	✔	✔	✔	✔	✔
Cluster-Wide Monitoring	✖	✖	✔	✔	✔	✔
Persistent Memory	✖	✖	✖	✔	✔	✔
Storage Class Memory	✖	✖	✖	✔	✔	✔
Server Message Block Encryption	✖	✖	✖	✖	✔	✔
Dedicated Microsoft Cloud Edition	✖	✖	✖	✖	✔	✔
Direct Upgrade to Windows Server 2025	✖	✔	✔	✔	✔	✔

Although Server 2022 and Server 2025 may look identical in feature sets, there are certain functions that only are available in the more expensive Server 2022 Datacentre Edition that are now in available in the better value Server 2025 Standard Edition. Furthermore, although many features may be present in Server 2022, Windows Server 2025 represents a significant step forward offering advancements in security, performance, cloud integration and containerisation features and capabilities.