# Missing shared scope configuration for Azure Reservations Canonical: https://www.pointfive.co/efficiency-hub/inefficiencies/missing-shared-scope-configuration-for-azure-reservations When reservations are scoped only to a single subscription, any unused capacity cannot be applied to matching resources in other subscriptions. By: Jeffrey Wang Updated: 2026-09-28 [Cloud Efficiency Hub](https://www.pointfive.co/efficiency-hub) # Missing Shared Scope Configuration for Azure Reservations The short version When reservations are scoped only to a single subscription, any unused capacity cannot be applied to matching resources in other subscriptions. [Jeffrey Wang](https://www.linkedin.com/in/jwang20/) Senior Manager, Cloud & Infrastructure Advisory @ PwC Azure service [Azure Reservations](https://www.pointfive.co/efficiency-hub/cloud-services/azure-reservations) Category [Compute](https://www.pointfive.co/efficiency-hub/service-category/compute) Reference CER-0145 Type Underutilized Commitment ## Explanation Why the waste happens and who it affects. This leads to underutilization of the committed reservation and continued on-demand charges in other parts of the organization. Enabling Shared scope allows eligible subscriptions in the same billing context (the EA enrollment or the MCA billing profile, which can span multiple Microsoft Entra tenants) to consume the reservation benefit, improving utilization and reducing overall spend. This is particularly impactful in environments with decentralized provisioning, such as across dev/test/prod subscriptions or multiple business units. ## Billing model The pricing dimensions that drive this cost. Prepaid commitment for reserved capacity (hourly usage covered by reservation, regardless of whether resource is provisioned) ## How to detect 4 checks to find it in your estate. - Check for reservations that consistently show low utilization over a representative time window - Evaluate whether matching on-demand resources exist in other subscriptions within the same billing context (EA enrollment or MCA billing profile) - Assess whether the reservation scope is currently set to 'Single' rather than 'Shared' - Determine if usage patterns across subscriptions are dynamic or uneven, which would benefit from shared scope flexibility ## How to fix 3 ways to remove the waste. - Change reservation scope from Single to Shared in the Azure Portal or via API - Use management group scope instead when the benefit should be shared only across the subscriptions in a specific management group - Reevaluate periodically to ensure the scope aligns with current organizational structure and usage distribution ## Documentation Vendor references for pricing and configuration. - [Buy an Azure reservation - Scope reservations learn.microsoft.com](https://learn.microsoft.com/en-us/azure/cost-management-billing/reservations/prepare-buy-reservation#scope-reservations) - [Manage Reservations for Azure resources learn.microsoft.com](https://learn.microsoft.com/en-us/azure/cost-management-billing/reservations/manage-reserved-vm-instance) - [View Azure reservation utilization learn.microsoft.com](https://learn.microsoft.com/en-us/azure/cost-management-billing/reservations/reservation-utilization) ## Related inefficiencies [Browse the library](https://www.pointfive.co/efficiency-hub) - Azure Reservations CER-0150 ### [Underutilized Azure Reserved Instance Due to Workload Drift](https://www.pointfive.co/efficiency-hub/inefficiencies/underutilized-azure-reserved-instance-due-to-workload-drift) As workloads evolve, Azure Reserved Instances (RIs) may no longer align with actual usage - due to refactoring, region changes, autoscaling, or instance-type drift. When this happens, the committed usage goes unused, while new workloads... Compute - Azure Reservations CER-0403 ### [Expiring Azure Reservations Without Renewal](https://www.pointfive.co/efficiency-hub/inefficiencies/expiring-azure-reservations-without-renewal) When an Azure reservation reaches the end of its term without automatic renewal or a replacement purchase, the covered VMs, databases and other resources keep running normally but are charged pay-as-you-go rates from that moment. Nothing... Compute - Azure Virtual Machines CER-0289 ### [Underutilized Azure Savings Plan Due to Overly Narrow Scope](https://www.pointfive.co/efficiency-hub/inefficiencies/underutilized-azure-savings-plan-due-to-overly-narrow-scope) An Azure Savings Plan is scoped too narrowly relative to where eligible compute usage actually runs. When usage is spread across multiple subscriptions or fluctuates significantly (for example, development and test workloads that are... Compute --- Source: the public page above. Product screenshots and illustrative interfaces are examples, not live customer data.