Hello @Pauli Harju
If you use your own Windows Server licenses with Software Assurance (SA) in Azure, you do not need to buy Windows Server Client Access Licenses (CALs) for your users or devices. The Azure Hybrid Benefit for Windows Server allows you to use your existing licenses with Software Assurance to pay a lower rate on Azure. The Azure Hybrid Benefit for Windows Server covers the cost of the Windows Server operating system, but it does not cover the cost of Windows Server Client Access Licenses (CALs). You will still need to purchase Windows Server CALs separately if you need them. The cost of Windows Server CALs is not included in the computing fee.
Please look at the follow extract from https://video2.skills-academy.com/en-us/windows-server/get-started/azure-hybrid-benefit?tabs=azure#what-qualifies-you-for-azure-hybrid-benefit
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