Hello Isabel. If you are deploying Excel and Word 2021 on a Windows Server in Azure with Remote Desktop Services, you have several licensing options depending on your organization’s licensing position and identity model.
If your organization is using Office LTSC 2021 (Standard or Professional Plus), you will have to purchase it from Volume Licensing and also ensure that it contains Software Assurance (SA). SA is necessary for your organization to deploy Office in a deployed/virtual environment such as Azure. This option is best for organizations that want a perpetual license and do not require cloud-connected capabilities. The organization needs only Active Directory (AD) or hybrid identity to use this approach, so you do not need Entra ID.
You can license users using Microsoft 365 Apps for Enterprise which is a subscription and includes Excel and Word. This will also work on RDS servers, but each user needs to be licensed. It also requires users to authenticate using Entra ID (previously Azure AD), so you will need a compatible environment to use this option. This is the preferred option if you are interested in getting updates regularly and access cloud services such as OneDrive and real time collaboration.
If you are using a Cloud Solution Provider (CSP), you can license Microsoft 365 Apps through CSP channels as long as they abide by Microsoft’s multi-tenant hosting rules. This will generally mean that you are either using CSP-hosted RDS SALs or licensing through Microsoft 365 Business Premium. Please note in either case, you will need Entra ID.
Regardless on the model you need valid RDS CALs with Software Assurance in order to legally access Office apps in Azure. Retail and OEM licenses are not supported in RDS scenarios. Just to note, Office LTSC 2021 is supported through October 2026 but does not include cloud features (like autosave or shared editing).
Best regards,