Consolidate App Service Plans but they don't show up

Hii @Patrick Prescott,

Thanks for reaching us regarding the issue.
Even though both of your App Service Plans show the same region, resource group, and OS, Azure may still not show one plan as an available target during Change App Service Plan. This happens when the two ASPs are not in the same underlying webspace, an internal deployment unit Azure uses.
Generally webspaces are internal deployment units Azure assigns when a plan is created.

• Once created, an ASP cannot be moved to another webspace.
• If two ASPs were originally created under different backend conditions, they may land in different webspaces, even if region/RG/OS match.
• When this happens, the Azure portal will silently hide the incompatible plan from the Change App Service Plan picker.

If the two ASPs are not in the same webspace, consolidation is not supported directly. The supported approach is:

Option: Re‑create one of the App Service Plans

1. Create a new ASP in the same region, resource group, and OS as the ASP you want to consolidate into.
   • Azure will place it in the same webspace automatically.
2. Migrate the Web App into the new ASP.

Migrating Your Windows Web App

For Windows Web Apps, you can use the portal feature: Development Tools > Clone App This allows you to clone the app into the new ASP with minimal effort and helps avoid manual re‑deployment.
Reference:
https://v4.hkg1.meaqua.org/en-us/azure/app-service/app-service-plan-manage?tabs=asyncscaleout
https://v4.hkg1.meaqua.org/en-us/azure/app-service/app-service-web-app-cloning
Kindly let us know if the above comment helps or you need further assistance on this issue.

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