For customers with Software Assurance, Azure Hybrid Benefit for Windows Server allows you to use your on-premises Windows Server licenses and run Windows virtual machines on Azure at a reduced cost. You can use Azure Hybrid Benefit for Windows Server to deploy new virtual machines from any Azure supported platform Windows Server image or Windows custom images
You can use the benefit with Windows Server Datacenter and Standard edition licenses covered with Software Assurance. Depending on the edition, you can convert or re-use your licenses to run Windows Server virtual machines in Azure and pay a lower base compute rate (Linux virtual machine rates).
If you are already using Azure: