Windows vs Linux VM cost: licences, BYOL and SQL Server

Par Rohit Athaide · Publié le 4 nov. 2026

Short answer: on the same size, a Windows machine costs more than a Linux one. The extra is a licence fee for the operating system, and sometimes for database software on top. It is charged every hour the machine runs and grows with the number of cores, so bigger machines pay more.

Key points

• Windows licence fees are added to the hourly rate or shown as a separate meter.
• SQL Server in a VM adds a second licence charge by core.
• Existing Microsoft licences may reduce the cost through programs such as Azure Hybrid Benefit.
• Our estimates use Linux, so Windows workloads cost more.
• Managed databases bundle the licence in the service price.

Where does the extra come from?

Cloud vendors add a per-hour or per-core licence charge to the machine rate for Windows Server. Some include it in a single hourly price, and some show it as a separate meter. SQL Server in a virtual machine adds a further licence charge by core. The licence is paid for every hour the machine runs.

Can I bring my own licence?

Microsoft licences you already own may let you use a discounted rate on Azure through Azure Hybrid Benefit, which requires active Software Assurance or a qualifying subscription. AWS, Google Cloud and Oracle offer their own routes for existing licences, usually on dedicated hosts or with licence mobility rules. The rules depend on your agreement with the software vendor, so check with them before you rely on a discount.

What does a worked example look like?

Made-up round numbers to show the method, not real prices. A server with 8 vCPUs runs all month (730 hours).

The Windows licence adds about a quarter. The database licence multiplies the bill by more than four. Halving the cores halves both licence lines, so right-sizing saves twice. With a managed database service the licence would sit inside the service price, and a licence you own may remove one or both lines.

How can I cut the cost?

1. Check whether you need Windows. Many .NET workloads now run on Linux.
2. Use a managed database instead of SQL Server in a VM, where the licence is bundled in the service price. See managed database or self-hosted.
3. Right-size. Licences scale with cores, so a smaller machine saves twice. See choosing a VM size.
4. Commit for steady loads. Reservations apply to the compute part. See reserved instances and savings plans.
5. Shut down test machines. See dev and test costs.

Which mistakes are common?

• Running SQL Server Enterprise features on Standard-sized needs.
• Leaving a Windows test machine on all night.
• Counting licences twice, once in the machine rate and again from your own agreement.
• Comparing a Linux price on one cloud with a Windows price on another.

Decision checklist

• Does the application need Windows?
• Do we own licences with Software Assurance?
• Can a managed database replace SQL Server in a VM?
• Is the operating system the same in every comparison?

Next steps

Match the operating system on both sides of any comparison. The virtual machine compare page shows which price lines we use, and VM instance equivalents shows how to match sizes.